I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some great support for this in the SL Extensions <http://slextensions.net> (ResourceSelector), *but I was wondering how everyone else does this, or if there is a better way* or if I'm just doin' it wrong? My View with the SL extension looks like this:
Are you trying to implement a sort of Login page then, after authentication, do you want to 'move' to main page?
Corrado
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 05:39 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Silverlight + MVVM = More questions
I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some great support for this in the SL Extensions <http://slextensions.net> (ResourceSelector), but I was wondering how everyone else does this, or if there is a better way or if I'm just doin' it wrong? My View with the SL extension looks like this:
Yeah, specifically here, that's exactly what I'm trying to accomplish. Generally, I want be able to "replace one control with another", and of course stick close to being MVVM. The ContentControl would eventually be replaced with something that would maybe do a transition when the content changed.
I know some things need a little home-brew TLC in SL (ie Commanding), but I am left wondering if I'm applying the pattern *incorrectly *and/or not leveraging the SL framework. So far, to me, making controls on a *lower *level makes a lot of sense, but gluing them together at a higher level is where my understanding of how to implement MVVM in SL falls apart.
-Jer
On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli <corradocava...@gmail.com>wrote:
> public ViewModelBase CurrentViewModel > { > get { return m_currentViewModel; } > set > { > m_currentViewModel = value; > InvokePropertyChanged("CurrentViewModel"); > } > } > }
> Now when my LoginViewModell "authenticates", I suppose I want to change the > "CurrentViewModel" property to a new view model. In my View, I would like > to change the DataTemplate "View" to the matching ViewModel, but it seems > something like this is not supported in SL. I found some great support for > this in the SL Extensions <http://slextensions.net> (ResourceSelector), *but > I was wondering how everyone else does this, or if there is a better way*or if I'm just doin' it wrong? My View with the SL extension looks like > this:
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 10:57 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Yeah, specifically here, that's exactly what I'm trying to accomplish. Generally, I want be able to "replace one control with another", and of course stick close to being MVVM. The ContentControl would eventually be replaced with something that would maybe do a transition when the content changed.
I know some things need a little home-brew TLC in SL (ie Commanding), but I am left wondering if I'm applying the pattern incorrectly and/or not leveraging the SL framework. So far, to me, making controls on a lower level makes a lot of sense, but gluing them together at a higher level is where my understanding of how to implement MVVM in SL falls apart.
-Jer
On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli <corradocava...@gmail.com> wrote:
Hi Jeremiah,
Are you trying to implement a sort of Login page then, after authentication, do you want to 'move' to main page?
Corrado
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 05:39 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Silverlight + MVVM = More questions
I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some great support for this in the SL Extensions <http://slextensions.net> (ResourceSelector), but I was wondering how everyone else does this, or if there is a better way or if I'm just doin' it wrong? My View with the SL extension looks like this:
I am with Corrado on that one. The idea in Silverlight is a "Page" based navigation. I put "Page" in quotes because it's actually a UserControl, but still, the idea is heavily inspired from WPF's navigation service. There are even frameworks implementing this (see http://blogs.telerik.com/BoryanaMiloshevska/Posts/08-10-03/Page_Navig... or_Silverlight_2_RC0.aspx for instance).
Another advantage of having the App taking care of the navigation is that it is able to read query string parameters or even the parameters entered in the "object" tag, and so a bookmarked navigation is also easy to implement.
On Behalf Of Corrado Cavalli Sent: Saturday, November 29, 2008 11:45 AM To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Think you're in wrong direction, you have to change rootvisual content, my application uses a navigation system based on this blog and it works great!
In my case, I changed the logic a bit because, after login only the internal area has to change based on navigation but approach is exactly the same
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 10:57 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Yeah, specifically here, that's exactly what I'm trying to accomplish. Generally, I want be able to "replace one control with another", and of course stick close to being MVVM. The ContentControl would eventually be replaced with something that would maybe do a transition when the content changed.
I know some things need a little home-brew TLC in SL (ie Commanding), but I am left wondering if I'm applying the pattern incorrectly and/or not leveraging the SL framework. So far, to me, making controls on a lower level makes a lot of sense, but gluing them together at a higher level is where my understanding of how to implement MVVM in SL falls apart.
-Jer
On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli <corradocava...@gmail.com> wrote:
Hi Jeremiah,
Are you trying to implement a sort of Login page then, after authentication, do you want to 'move' to main page?
Corrado
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 05:39 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Silverlight + MVVM = More questions
I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some great support for this in the SL Extensions <http://slextensions.net> (ResourceSelector), but I was wondering how everyone else does this, or if there is a better way or if I'm just doin' it wrong? My View with the SL extension looks like this:
No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.11/1818 - Release Date: 11/28/2008 7:31 PM
Thanks guys. This surely answers my question on moving from the LoginView to AnotherView. But does this navigation method work well on all levels of the UI?
For an example, say I had a LionView, TigerView and BearView (all with their complimentary ViewModels). Now visualize a stereotypical LOB "Page", with a handful of controls (ie product lists, datagrids). Say one of these controls was a 200x200 containing 3 buttons. Let's call it the ZooView. When any of these 3 buttons are clicked, it would load up a "LionView", "TigerView" and so on, within the ZooView. Of course in this situation I wouldn't want to navigate to a whole new "RootVisual", just "navigate" one control to another.
This is all really trivial, but I feel like I "break" the MVVM pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's no DataType property on the DataTemplate in SL, so the ResourceSelector from the SL extensions lib seems to fill the gap in making the SL View more intelligent as to what DataTemplate (or View) to use with a given ViewModel.
Hope this email wasn't a diaremail =P
-Jer
On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP]
> I am with Corrado on that one. The idea in Silverlight is a "Page" based > navigation. I put "Page" in quotes because it's actually a UserControl, but > still, the idea is heavily inspired from WPF's navigation service. There > are > even frameworks implementing this (see
> Another advantage of having the App taking care of the navigation is that > it > is able to read query string parameters or even the parameters entered in > the "object" tag, and so a bookmarked navigation is also easy to implement.
> Cheers, > Laurent
> -----Original Message----- > From: wpf-disciples@googlegroups.com [mailto: > wpf-disciples@googlegroups.com] > On Behalf Of Corrado Cavalli > Sent: Saturday, November 29, 2008 11:45 AM > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
> Think you're in wrong direction, you have to change rootvisual content, > my application uses a navigation system based on this blog and it works > great!
> In my case, I changed the logic a bit because, after login only the > internal area has to change based on navigation but approach is exactly > the same
> From: wpf-disciples@googlegroups.com > [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill > Sent: sabato 29 novembre 2008 10:57 > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
> Yeah, specifically here, that's exactly what I'm trying to accomplish. > Generally, I want be able to "replace one control with another", and of > course stick close to being MVVM. The ContentControl would eventually > be replaced with something that would maybe do a transition when the > content changed.
> I know some things need a little home-brew TLC in SL (ie Commanding), > but I am left wondering if I'm applying the pattern incorrectly and/or > not leveraging the SL framework. So far, to me, making controls on a > lower level makes a lot of sense, but gluing them together at a higher > level is where my understanding of how to implement MVVM in SL falls > apart.
> -Jer
> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli > <corradocava...@gmail.com> wrote:
> Hi Jeremiah,
> Are you trying to implement a sort of Login page then, after > authentication, do you want to 'move' to main page?
> Corrado
> From: wpf-disciples@googlegroups.com > [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill > Sent: sabato 29 novembre 2008 05:39 > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Silverlight + MVVM = More questions
> I'm still trying to grok, as they say, MVVM in Silverlight. So if any > of this sounds ignorant, don't be shy about letting me know.
> So essentially I have a ViewModel such as this:
> public class MainLayoutViewModel : ViewModelBase > { > private LoginViewModel m_loginController = new LoginViewModel(); > private TestViewModel m_testController = new TestViewModel(); > private ViewModelBase m_currentViewModel;
> public ViewModelBase CurrentViewModel > { > get { return m_currentViewModel; } > set > { > m_currentViewModel = value; > InvokePropertyChanged("CurrentViewModel"); > } > } > }
> Now when my LoginViewModell "authenticates", I suppose I want to change > the "CurrentViewModel" property to a new view model. In my View, I > would like to change the DataTemplate "View" to the matching ViewModel, > but it seems something like this is not supported in SL. I found some > great support for this in the SL Extensions <http://slextensions.net> > (ResourceSelector), but I was wondering how everyone else does this, or > if there is a better way or if I'm just doin' it wrong? My View with > the SL extension looks like this:
Nice usage of "diaremail"...though I don't think your reply qualifies as one. :)
There are two pieces to this puzzle, imo. One piece decides *what* to show, the other piece decides *how* to show it. I think the first piece is properly handled in the ViewModel, as you suggested. The second piece should be handled as a platform-level service, like typed DataTemplates in WPF. However, as you pointed out, since SL doesn't have this, I think using an extension class is ideal.
What you're describing makes sense to me. What exactly is the problem that you are concerned about?
Josh
On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill <
jeremiah.morr...@gmail.com> wrote: > Thanks guys. This surely answers my question on moving from the LoginView > to AnotherView. But does this navigation method work well on all levels of > the UI?
> For an example, say I had a LionView, TigerView and BearView (all with > their complimentary ViewModels). Now visualize a stereotypical LOB "Page", > with a handful of controls (ie product lists, datagrids). Say one of these > controls was a 200x200 containing 3 buttons. Let's call it the ZooView. > When any of these 3 buttons are clicked, it would load up a "LionView", > "TigerView" and so on, within the ZooView. Of course in this situation I > wouldn't want to navigate to a whole new "RootVisual", just "navigate" one > control to another.
> This is all really trivial, but I feel like I "break" the MVVM pattern and > it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's > no DataType property on the DataTemplate in SL, so the ResourceSelector from > the SL extensions lib seems to fill the gap in making the SL View more > intelligent as to what DataTemplate (or View) to use with a given ViewModel.
> Hope this email wasn't a diaremail =P
> -Jer
> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] > <laur...@galasoft.ch> wrote:
>> I am with Corrado on that one. The idea in Silverlight is a "Page" based >> navigation. I put "Page" in quotes because it's actually a UserControl, >> but >> still, the idea is heavily inspired from WPF's navigation service. There >> are >> even frameworks implementing this (see
>> Another advantage of having the App taking care of the navigation is that >> it >> is able to read query string parameters or even the parameters entered in >> the "object" tag, and so a bookmarked navigation is also easy to >> implement.
>> Cheers, >> Laurent
>> -----Original Message----- >> From: wpf-disciples@googlegroups.com [mailto: >> wpf-disciples@googlegroups.com] >> On Behalf Of Corrado Cavalli >> Sent: Saturday, November 29, 2008 11:45 AM >> To: wpf-disciples@googlegroups.com >> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>> Think you're in wrong direction, you have to change rootvisual content, >> my application uses a navigation system based on this blog and it works >> great!
>> In my case, I changed the logic a bit because, after login only the >> internal area has to change based on navigation but approach is exactly >> the same
>> From: wpf-disciples@googlegroups.com >> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >> Sent: sabato 29 novembre 2008 10:57 >> To: wpf-disciples@googlegroups.com >> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >> Generally, I want be able to "replace one control with another", and of >> course stick close to being MVVM. The ContentControl would eventually >> be replaced with something that would maybe do a transition when the >> content changed.
>> I know some things need a little home-brew TLC in SL (ie Commanding), >> but I am left wondering if I'm applying the pattern incorrectly and/or >> not leveraging the SL framework. So far, to me, making controls on a >> lower level makes a lot of sense, but gluing them together at a higher >> level is where my understanding of how to implement MVVM in SL falls >> apart.
>> -Jer
>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >> <corradocava...@gmail.com> wrote:
>> Hi Jeremiah,
>> Are you trying to implement a sort of Login page then, after >> authentication, do you want to 'move' to main page?
>> Corrado
>> From: wpf-disciples@googlegroups.com >> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >> Sent: sabato 29 novembre 2008 05:39 >> To: wpf-disciples@googlegroups.com >> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>> I'm still trying to grok, as they say, MVVM in Silverlight. So if any >> of this sounds ignorant, don't be shy about letting me know.
>> So essentially I have a ViewModel such as this:
>> public class MainLayoutViewModel : ViewModelBase >> { >> private LoginViewModel m_loginController = new LoginViewModel(); >> private TestViewModel m_testController = new TestViewModel(); >> private ViewModelBase m_currentViewModel;
>> public ViewModelBase CurrentViewModel >> { >> get { return m_currentViewModel; } >> set >> { >> m_currentViewModel = value; >> InvokePropertyChanged("CurrentViewModel"); >> } >> } >> }
>> Now when my LoginViewModell "authenticates", I suppose I want to change >> the "CurrentViewModel" property to a new view model. In my View, I >> would like to change the DataTemplate "View" to the matching ViewModel, >> but it seems something like this is not supported in SL. I found some >> great support for this in the SL Extensions <http://slextensions.net> >> (ResourceSelector), but I was wondering how everyone else does this, or >> if there is a better way or if I'm just doin' it wrong? My View with >> the SL extension looks like this:
I was looking for validation of my approach...I'd hate to have to unlearn anything ;). All the MVVM SL examples I've looked at, have a single "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be databound to a collection of VMs. I have not seen an MVVM example showing how to dynamically change specific controls in the View *from* the ViewModel. I was starting to clutter my View's codebehind to handle a lot of that, so thats why I said it started being like the MVP/MVVM hybrid...and it surely didn't look as clean as a WPF MVVM.
My main concern, was that life seemed good with a 3rd party solution...which makes me sometimes think I'm not leveraging the framework I'm using correctly. And also wondering how anyone else does stuff like this within their own applications.
Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> wrote: > Nice usage of "diaremail"...though I don't think your reply qualifies as > one. :)
> There are two pieces to this puzzle, imo. One piece decides *what* to > show, the other piece decides *how* to show it. I think the first piece > is properly handled in the ViewModel, as you suggested. The second piece > should be handled as a platform-level service, like typed DataTemplates in > WPF. However, as you pointed out, since SL doesn't have this, I think using > an extension class is ideal.
> What you're describing makes sense to me. What exactly is the problem that > you are concerned about?
> Josh
> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
>> Thanks guys. This surely answers my question on moving from the LoginView >> to AnotherView. But does this navigation method work well on all levels of >> the UI?
>> For an example, say I had a LionView, TigerView and BearView (all with >> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >> with a handful of controls (ie product lists, datagrids). Say one of these >> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >> When any of these 3 buttons are clicked, it would load up a "LionView", >> "TigerView" and so on, within the ZooView. Of course in this situation I >> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >> control to another.
>> This is all really trivial, but I feel like I "break" the MVVM pattern and >> it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's >> no DataType property on the DataTemplate in SL, so the ResourceSelector from >> the SL extensions lib seems to fill the gap in making the SL View more >> intelligent as to what DataTemplate (or View) to use with a given ViewModel.
>> Hope this email wasn't a diaremail =P
>> -Jer
>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >> <laur...@galasoft.ch> wrote:
>>> I am with Corrado on that one. The idea in Silverlight is a "Page" based >>> navigation. I put "Page" in quotes because it's actually a UserControl, >>> but >>> still, the idea is heavily inspired from WPF's navigation service. There >>> are >>> even frameworks implementing this (see
>>> Another advantage of having the App taking care of the navigation is that >>> it >>> is able to read query string parameters or even the parameters entered in >>> the "object" tag, and so a bookmarked navigation is also easy to >>> implement.
>>> Cheers, >>> Laurent
>>> -----Original Message----- >>> From: wpf-disciples@googlegroups.com [mailto: >>> wpf-disciples@googlegroups.com] >>> On Behalf Of Corrado Cavalli >>> Sent: Saturday, November 29, 2008 11:45 AM >>> To: wpf-disciples@googlegroups.com >>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>> Think you're in wrong direction, you have to change rootvisual content, >>> my application uses a navigation system based on this blog and it works >>> great!
>>> In my case, I changed the logic a bit because, after login only the >>> internal area has to change based on navigation but approach is exactly >>> the same
>>> From: wpf-disciples@googlegroups.com >>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>> Sent: sabato 29 novembre 2008 10:57 >>> To: wpf-disciples@googlegroups.com >>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >>> Generally, I want be able to "replace one control with another", and of >>> course stick close to being MVVM. The ContentControl would eventually >>> be replaced with something that would maybe do a transition when the >>> content changed.
>>> I know some things need a little home-brew TLC in SL (ie Commanding), >>> but I am left wondering if I'm applying the pattern incorrectly and/or >>> not leveraging the SL framework. So far, to me, making controls on a >>> lower level makes a lot of sense, but gluing them together at a higher >>> level is where my understanding of how to implement MVVM in SL falls >>> apart.
>>> -Jer
>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>> <corradocava...@gmail.com> wrote:
>>> Hi Jeremiah,
>>> Are you trying to implement a sort of Login page then, after >>> authentication, do you want to 'move' to main page?
>>> Corrado
>>> From: wpf-disciples@googlegroups.com >>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>> Sent: sabato 29 novembre 2008 05:39 >>> To: wpf-disciples@googlegroups.com >>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if any >>> of this sounds ignorant, don't be shy about letting me know.
>>> So essentially I have a ViewModel such as this:
>>> public class MainLayoutViewModel : ViewModelBase >>> { >>> private LoginViewModel m_loginController = new LoginViewModel(); >>> private TestViewModel m_testController = new TestViewModel(); >>> private ViewModelBase m_currentViewModel;
>>> public ViewModelBase CurrentViewModel >>> { >>> get { return m_currentViewModel; } >>> set >>> { >>> m_currentViewModel = value; >>> InvokePropertyChanged("CurrentViewModel"); >>> } >>> } >>> }
>>> Now when my LoginViewModell "authenticates", I suppose I want to change >>> the "CurrentViewModel" property to a new view model. In my View, I >>> would like to change the DataTemplate "View" to the matching ViewModel, >>> but it seems something like this is not supported in SL. I found some >>> great support for this in the SL Extensions <http://slextensions.net> >>> (ResourceSelector), but I was wondering how everyone else does this, or >>> if there is a better way or if I'm just doin' it wrong? My View with >>> the SL extension looks like this:
I don't know if this trick will work in Silverlight but one technique I used in WPF was to have a Control as a place holder and used a trigger to change the template (and thus contents) of the control based on what object I wanted to display. I used it similar to your "Zoo" scenario, where there were multiple classes of objects that I wanted to perform the same operation upon. I never wrote about the technique because I wasn't sure if it qualified as very useful or not. But since it seems someone else can use it, I can give a quick post about it.
On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill <
jeremiah.morr...@gmail.com> wrote: > I was looking for validation of my approach...I'd hate to have to unlearn > anything ;). All the MVVM SL examples I've looked at, have a single "Page" > with a VM and maybe an ItemsControl/Panel or ListBox, that would be > databound to a collection of VMs. I have not seen an MVVM example showing > how to dynamically change specific controls in the View *from* the > ViewModel. I was starting to clutter my View's codebehind to handle a lot > of that, so thats why I said it started being like the MVP/MVVM hybrid...and > it surely didn't look as clean as a WPF MVVM.
> My main concern, was that life seemed good with a 3rd party > solution...which makes me sometimes think I'm not leveraging the framework > I'm using correctly. And also wondering how anyone else does stuff like > this within their own applications.
> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
> -Jer
> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>> Nice usage of "diaremail"...though I don't think your reply qualifies as >> one. :)
>> There are two pieces to this puzzle, imo. One piece decides *what* to >> show, the other piece decides *how* to show it. I think the first piece >> is properly handled in the ViewModel, as you suggested. The second piece >> should be handled as a platform-level service, like typed DataTemplates in >> WPF. However, as you pointed out, since SL doesn't have this, I think using >> an extension class is ideal.
>> What you're describing makes sense to me. What exactly is the problem >> that you are concerned about?
>> Josh
>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>>> Thanks guys. This surely answers my question on moving from the >>> LoginView to AnotherView. But does this navigation method work well on all >>> levels of the UI?
>>> For an example, say I had a LionView, TigerView and BearView (all with >>> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >>> with a handful of controls (ie product lists, datagrids). Say one of these >>> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >>> When any of these 3 buttons are clicked, it would load up a "LionView", >>> "TigerView" and so on, within the ZooView. Of course in this situation I >>> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >>> control to another.
>>> This is all really trivial, but I feel like I "break" the MVVM pattern >>> and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. >>> There's no DataType property on the DataTemplate in SL, so the >>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>> given ViewModel.
>>> Hope this email wasn't a diaremail =P
>>> -Jer
>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>> <laur...@galasoft.ch> wrote:
>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" based >>>> navigation. I put "Page" in quotes because it's actually a UserControl, >>>> but >>>> still, the idea is heavily inspired from WPF's navigation service. There >>>> are >>>> even frameworks implementing this (see
>>>> Another advantage of having the App taking care of the navigation is >>>> that it >>>> is able to read query string parameters or even the parameters entered >>>> in >>>> the "object" tag, and so a bookmarked navigation is also easy to >>>> implement.
>>>> Cheers, >>>> Laurent
>>>> -----Original Message----- >>>> From: wpf-disciples@googlegroups.com [mailto: >>>> wpf-disciples@googlegroups.com] >>>> On Behalf Of Corrado Cavalli >>>> Sent: Saturday, November 29, 2008 11:45 AM >>>> To: wpf-disciples@googlegroups.com >>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>> Think you're in wrong direction, you have to change rootvisual >>>> content, >>>> my application uses a navigation system based on this blog and it works >>>> great!
>>>> In my case, I changed the logic a bit because, after login only the >>>> internal area has to change based on navigation but approach is exactly >>>> the same
>>>> From: wpf-disciples@googlegroups.com >>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>> Sent: sabato 29 novembre 2008 10:57 >>>> To: wpf-disciples@googlegroups.com >>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >>>> Generally, I want be able to "replace one control with another", and of >>>> course stick close to being MVVM. The ContentControl would eventually >>>> be replaced with something that would maybe do a transition when the >>>> content changed.
>>>> I know some things need a little home-brew TLC in SL (ie Commanding), >>>> but I am left wondering if I'm applying the pattern incorrectly and/or >>>> not leveraging the SL framework. So far, to me, making controls on a >>>> lower level makes a lot of sense, but gluing them together at a higher >>>> level is where my understanding of how to implement MVVM in SL falls >>>> apart.
>>>> -Jer
>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>> <corradocava...@gmail.com> wrote:
>>>> Hi Jeremiah,
>>>> Are you trying to implement a sort of Login page then, after >>>> authentication, do you want to 'move' to main page?
>>>> Corrado
>>>> From: wpf-disciples@googlegroups.com >>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>> Sent: sabato 29 novembre 2008 05:39 >>>> To: wpf-disciples@googlegroups.com >>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if any >>>> of this sounds ignorant, don't be shy about letting me know.
>>>> So essentially I have a ViewModel such as this:
>>>> public class MainLayoutViewModel : ViewModelBase >>>> { >>>> private LoginViewModel m_loginController = new LoginViewModel(); >>>> private TestViewModel m_testController = new TestViewModel(); >>>> private ViewModelBase m_currentViewModel;
>>>> public ViewModelBase CurrentViewModel >>>> { >>>> get { return m_currentViewModel; } >>>> set >>>> { >>>> m_currentViewModel = value; >>>> InvokePropertyChanged("CurrentViewModel"); >>>> } >>>> } >>>> }
>>>> Now when my LoginViewModell "authenticates", I suppose I want to change >>>> the "CurrentViewModel" property to a new view model. In my View, I >>>> would like to change the DataTemplate "View" to the matching ViewModel, >>>> but it seems something like this is not supported in SL. I found some >>>> great support for this in the SL Extensions <http://slextensions.net> >>>> (ResourceSelector), but I was wondering how everyone else does this, >>>> or >>>> if there is a better way or if I'm just doin' it wrong? My View with >>>> the SL extension looks like this:
I think triggers are pretty limited in SL 2.0. AFAIK, there are only event triggers, but you can't define your own routed events. Not sure that can be implemented without some home-brew infrastructure. This SL Extension library has the makings of a routed event framework, but I have yet to try it on.
On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote: > I don't know if this trick will work in Silverlight but one technique I > used in WPF was to have a Control as a place holder and used a trigger to > change the template (and thus contents) of the control based on what object > I wanted to display. I used it similar to your "Zoo" scenario, where there > were multiple classes of objects that I wanted to perform the same operation > upon. I never wrote about the technique because I wasn't sure if it > qualified as very useful or not. But since it seems someone else can use it, > I can give a quick post about it.
> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
>> I was looking for validation of my approach...I'd hate to have to unlearn >> anything ;). All the MVVM SL examples I've looked at, have a single "Page" >> with a VM and maybe an ItemsControl/Panel or ListBox, that would be >> databound to a collection of VMs. I have not seen an MVVM example showing >> how to dynamically change specific controls in the View *from* the >> ViewModel. I was starting to clutter my View's codebehind to handle a lot >> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >> it surely didn't look as clean as a WPF MVVM.
>> My main concern, was that life seemed good with a 3rd party >> solution...which makes me sometimes think I'm not leveraging the framework >> I'm using correctly. And also wondering how anyone else does stuff like >> this within their own applications.
>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>> -Jer
>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>> Nice usage of "diaremail"...though I don't think your reply qualifies as >>> one. :)
>>> There are two pieces to this puzzle, imo. One piece decides *what* to >>> show, the other piece decides *how* to show it. I think the first piece >>> is properly handled in the ViewModel, as you suggested. The second piece >>> should be handled as a platform-level service, like typed DataTemplates in >>> WPF. However, as you pointed out, since SL doesn't have this, I think using >>> an extension class is ideal.
>>> What you're describing makes sense to me. What exactly is the problem >>> that you are concerned about?
>>> Josh
>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>>> Thanks guys. This surely answers my question on moving from the >>>> LoginView to AnotherView. But does this navigation method work well on all >>>> levels of the UI?
>>>> For an example, say I had a LionView, TigerView and BearView (all with >>>> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >>>> with a handful of controls (ie product lists, datagrids). Say one of these >>>> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >>>> When any of these 3 buttons are clicked, it would load up a "LionView", >>>> "TigerView" and so on, within the ZooView. Of course in this situation I >>>> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >>>> control to another.
>>>> This is all really trivial, but I feel like I "break" the MVVM pattern >>>> and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. >>>> There's no DataType property on the DataTemplate in SL, so the >>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>> given ViewModel.
>>>> Hope this email wasn't a diaremail =P
>>>> -Jer
>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>> <laur...@galasoft.ch> wrote:
>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>> based >>>>> navigation. I put "Page" in quotes because it's actually a UserControl, >>>>> but >>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>> There are >>>>> even frameworks implementing this (see
>>>>> Another advantage of having the App taking care of the navigation is >>>>> that it >>>>> is able to read query string parameters or even the parameters entered >>>>> in >>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>> implement.
>>>>> Cheers, >>>>> Laurent
>>>>> -----Original Message----- >>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>> wpf-disciples@googlegroups.com] >>>>> On Behalf Of Corrado Cavalli >>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>> To: wpf-disciples@googlegroups.com >>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>> Think you're in wrong direction, you have to change rootvisual >>>>> content, >>>>> my application uses a navigation system based on this blog and it works >>>>> great!
>>>>> In my case, I changed the logic a bit because, after login only the >>>>> internal area has to change based on navigation but approach is exactly >>>>> the same
>>>>> From: wpf-disciples@googlegroups.com >>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>>> Sent: sabato 29 novembre 2008 10:57 >>>>> To: wpf-disciples@googlegroups.com >>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >>>>> Generally, I want be able to "replace one control with another", and of >>>>> course stick close to being MVVM. The ContentControl would eventually >>>>> be replaced with something that would maybe do a transition when the >>>>> content changed.
>>>>> I know some things need a little home-brew TLC in SL (ie Commanding), >>>>> but I am left wondering if I'm applying the pattern incorrectly and/or >>>>> not leveraging the SL framework. So far, to me, making controls on a >>>>> lower level makes a lot of sense, but gluing them together at a higher >>>>> level is where my understanding of how to implement MVVM in SL falls >>>>> apart.
>>>>> -Jer
>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>> <corradocava...@gmail.com> wrote:
>>>>> Hi Jeremiah,
>>>>> Are you trying to implement a sort of Login page then, after >>>>> authentication, do you want to 'move' to main page?
>>>>> Corrado
>>>>> From: wpf-disciples@googlegroups.com >>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>>> Sent: sabato 29 novembre 2008 05:39 >>>>> To: wpf-disciples@googlegroups.com >>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if any >>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>> So essentially I have a ViewModel such as this:
>>>>> public class MainLayoutViewModel : ViewModelBase >>>>> { >>>>> private LoginViewModel m_loginController = new LoginViewModel(); >>>>> private TestViewModel m_testController = new TestViewModel(); >>>>> private ViewModelBase m_currentViewModel;
>>>>> public ViewModelBase CurrentViewModel >>>>> { >>>>> get { return m_currentViewModel; } >>>>> set >>>>> { >>>>> m_currentViewModel = value; >>>>> InvokePropertyChanged("CurrentViewModel"); >>>>> } >>>>> } >>>>> }
>>>>> Now when my LoginViewModell "authenticates", I suppose I want to change >>>>> the "CurrentViewModel" property to a new view model. In my View, I >>>>> would like to change the DataTemplate "View" to the matching ViewModel, >>>>> but it seems something like this is not supported in SL. I found some >>>>> great support for this in the SL Extensions <http://slextensions.net> >>>>> (ResourceSelector), but I was wondering how everyone else does this, >>>>> or >>>>> if there is a better way or if I'm just doin' it wrong? My View with >>>>> the SL extension looks like this:
jeremiah.morr...@gmail.com> wrote: > I think triggers are pretty limited in SL 2.0. AFAIK, there are only event > triggers, but you can't define your own routed events. Not sure that can be > implemented without some home-brew infrastructure. This SL Extension > library has the makings of a routed event framework, but I have yet to try > it on.
> -Jer
> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>> I don't know if this trick will work in Silverlight but one technique I >> used in WPF was to have a Control as a place holder and used a trigger to >> change the template (and thus contents) of the control based on what object >> I wanted to display. I used it similar to your "Zoo" scenario, where there >> were multiple classes of objects that I wanted to perform the same operation >> upon. I never wrote about the technique because I wasn't sure if it >> qualified as very useful or not. But since it seems someone else can use it, >> I can give a quick post about it.
>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>>> I was looking for validation of my approach...I'd hate to have to unlearn >>> anything ;). All the MVVM SL examples I've looked at, have a single "Page" >>> with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>> databound to a collection of VMs. I have not seen an MVVM example showing >>> how to dynamically change specific controls in the View *from* the >>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>> it surely didn't look as clean as a WPF MVVM.
>>> My main concern, was that life seemed good with a 3rd party >>> solution...which makes me sometimes think I'm not leveraging the framework >>> I'm using correctly. And also wondering how anyone else does stuff like >>> this within their own applications.
>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>> -Jer
>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>>> Nice usage of "diaremail"...though I don't think your reply qualifies as >>>> one. :)
>>>> There are two pieces to this puzzle, imo. One piece decides *what* to >>>> show, the other piece decides *how* to show it. I think the first >>>> piece is properly handled in the ViewModel, as you suggested. The second >>>> piece should be handled as a platform-level service, like typed >>>> DataTemplates in WPF. However, as you pointed out, since SL doesn't have >>>> this, I think using an extension class is ideal.
>>>> What you're describing makes sense to me. What exactly is the problem >>>> that you are concerned about?
>>>> Josh
>>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>>> jeremiah.morr...@gmail.com> wrote:
>>>>> Thanks guys. This surely answers my question on moving from the >>>>> LoginView to AnotherView. But does this navigation method work well on all >>>>> levels of the UI?
>>>>> For an example, say I had a LionView, TigerView and BearView (all with >>>>> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >>>>> with a handful of controls (ie product lists, datagrids). Say one of these >>>>> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >>>>> When any of these 3 buttons are clicked, it would load up a "LionView", >>>>> "TigerView" and so on, within the ZooView. Of course in this situation I >>>>> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >>>>> control to another.
>>>>> This is all really trivial, but I feel like I "break" the MVVM pattern >>>>> and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. >>>>> There's no DataType property on the DataTemplate in SL, so the >>>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>>> given ViewModel.
>>>>> Hope this email wasn't a diaremail =P
>>>>> -Jer
>>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>>> <laur...@galasoft.ch> wrote:
>>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>>> based >>>>>> navigation. I put "Page" in quotes because it's actually a >>>>>> UserControl, but >>>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>>> There are >>>>>> even frameworks implementing this (see
>>>>>> Another advantage of having the App taking care of the navigation is >>>>>> that it >>>>>> is able to read query string parameters or even the parameters entered >>>>>> in >>>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>>> implement.
>>>>>> Cheers, >>>>>> Laurent
>>>>>> -----Original Message----- >>>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>>> wpf-disciples@googlegroups.com] >>>>>> On Behalf Of Corrado Cavalli >>>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>>> To: wpf-disciples@googlegroups.com >>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>> Think you're in wrong direction, you have to change rootvisual >>>>>> content, >>>>>> my application uses a navigation system based on this blog and it >>>>>> works >>>>>> great!
>>>>>> In my case, I changed the logic a bit because, after login only the >>>>>> internal area has to change based on navigation but approach is >>>>>> exactly >>>>>> the same
>>>>>> From: wpf-disciples@googlegroups.com >>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>>>> Sent: sabato 29 novembre 2008 10:57 >>>>>> To: wpf-disciples@googlegroups.com >>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >>>>>> Generally, I want be able to "replace one control with another", and >>>>>> of >>>>>> course stick close to being MVVM. The ContentControl would eventually >>>>>> be replaced with something that would maybe do a transition when the >>>>>> content changed.
>>>>>> I know some things need a little home-brew TLC in SL (ie Commanding), >>>>>> but I am left wondering if I'm applying the pattern incorrectly and/or >>>>>> not leveraging the SL framework. So far, to me, making controls on a >>>>>> lower level makes a lot of sense, but gluing them together at a higher >>>>>> level is where my understanding of how to implement MVVM in SL falls >>>>>> apart.
>>>>>> -Jer
>>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>>> <corradocava...@gmail.com> wrote:
>>>>>> Hi Jeremiah,
>>>>>> Are you trying to implement a sort of Login page then, after >>>>>> authentication, do you want to 'move' to main page?
>>>>>> Corrado
>>>>>> From: wpf-disciples@googlegroups.com >>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>>>>> Sent: sabato 29 novembre 2008 05:39 >>>>>> To: wpf-disciples@googlegroups.com >>>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if any >>>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>>> So essentially I have a ViewModel such as this:
>>>>>> public class MainLayoutViewModel : ViewModelBase >>>>>> { >>>>>> private LoginViewModel m_loginController = new >>>>>> LoginViewModel(); >>>>>> private TestViewModel m_testController = new TestViewModel(); >>>>>> private ViewModelBase m_currentViewModel;
>>>>>> public ViewModelBase CurrentViewModel >>>>>> { >>>>>> get { return m_currentViewModel; } >>>>>> set >>>>>> { >>>>>> m_currentViewModel = value; >>>>>> InvokePropertyChanged("CurrentViewModel"); >>>>>> } >>>>>> } >>>>>> }
>>>>>> Now when my LoginViewModell "authenticates", I suppose I want to >>>>>> change >>>>>> the "CurrentViewModel" property to a new view model. In my View, I >>>>>> would like to change the DataTemplate "View" to the matching >>>>>> ViewModel, >>>>>> but it seems something like this is not supported in SL. I found some >>>>>> great support for this in the SL Extensions <http://slextensions.net> >>>>>> (ResourceSelector), but I was wondering how everyone else does this, >>>>>> or >>>>>> if there is a better way or if I'm just doin' it wrong? My View with >>>>>> the SL extension looks like this:
On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote: > So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on > that one?
> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >> event triggers, but you can't define your own routed events. Not sure that >> can be implemented without some home-brew infrastructure. This SL Extension >> library has the makings of a routed event framework, but I have yet to try >> it on.
>> -Jer
>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>> I don't know if this trick will work in Silverlight but one technique I >>> used in WPF was to have a Control as a place holder and used a trigger to >>> change the template (and thus contents) of the control based on what object >>> I wanted to display. I used it similar to your "Zoo" scenario, where there >>> were multiple classes of objects that I wanted to perform the same operation >>> upon. I never wrote about the technique because I wasn't sure if it >>> qualified as very useful or not. But since it seems someone else can use it, >>> I can give a quick post about it.
>>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>>> I was looking for validation of my approach...I'd hate to have to >>>> unlearn anything ;). All the MVVM SL examples I've looked at, have a single >>>> "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>>> databound to a collection of VMs. I have not seen an MVVM example showing >>>> how to dynamically change specific controls in the View *from* the >>>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>>> it surely didn't look as clean as a WPF MVVM.
>>>> My main concern, was that life seemed good with a 3rd party >>>> solution...which makes me sometimes think I'm not leveraging the framework >>>> I'm using correctly. And also wondering how anyone else does stuff like >>>> this within their own applications.
>>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>>> -Jer
>>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>>>> Nice usage of "diaremail"...though I don't think your reply qualifies >>>>> as one. :)
>>>>> There are two pieces to this puzzle, imo. One piece decides *what* to >>>>> show, the other piece decides *how* to show it. I think the first >>>>> piece is properly handled in the ViewModel, as you suggested. The second >>>>> piece should be handled as a platform-level service, like typed >>>>> DataTemplates in WPF. However, as you pointed out, since SL doesn't have >>>>> this, I think using an extension class is ideal.
>>>>> What you're describing makes sense to me. What exactly is the problem >>>>> that you are concerned about?
>>>>> Josh
>>>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>>>> jeremiah.morr...@gmail.com> wrote:
>>>>>> Thanks guys. This surely answers my question on moving from the >>>>>> LoginView to AnotherView. But does this navigation method work well on all >>>>>> levels of the UI?
>>>>>> For an example, say I had a LionView, TigerView and BearView (all with >>>>>> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >>>>>> with a handful of controls (ie product lists, datagrids). Say one of these >>>>>> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >>>>>> When any of these 3 buttons are clicked, it would load up a "LionView", >>>>>> "TigerView" and so on, within the ZooView. Of course in this situation I >>>>>> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >>>>>> control to another.
>>>>>> This is all really trivial, but I feel like I "break" the MVVM pattern >>>>>> and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. >>>>>> There's no DataType property on the DataTemplate in SL, so the >>>>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>>>> given ViewModel.
>>>>>> Hope this email wasn't a diaremail =P
>>>>>> -Jer
>>>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>>>> <laur...@galasoft.ch> wrote:
>>>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>>>> based >>>>>>> navigation. I put "Page" in quotes because it's actually a >>>>>>> UserControl, but >>>>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>>>> There are >>>>>>> even frameworks implementing this (see
>>>>>>> Another advantage of having the App taking care of the navigation is >>>>>>> that it >>>>>>> is able to read query string parameters or even the parameters >>>>>>> entered in >>>>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>>>> implement.
>>>>>>> Cheers, >>>>>>> Laurent
>>>>>>> -----Original Message----- >>>>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>>>> wpf-disciples@googlegroups.com] >>>>>>> On Behalf Of Corrado Cavalli >>>>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>>>> To: wpf-disciples@googlegroups.com >>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>> Think you're in wrong direction, you have to change rootvisual >>>>>>> content, >>>>>>> my application uses a navigation system based on this blog and it >>>>>>> works >>>>>>> great!
>>>>>>> In my case, I changed the logic a bit because, after login only the >>>>>>> internal area has to change based on navigation but approach is >>>>>>> exactly >>>>>>> the same
>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>> Morrill >>>>>>> Sent: sabato 29 novembre 2008 10:57 >>>>>>> To: wpf-disciples@googlegroups.com >>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>> Yeah, specifically here, that's exactly what I'm trying to >>>>>>> accomplish. >>>>>>> Generally, I want be able to "replace one control with another", and >>>>>>> of >>>>>>> course stick close to being MVVM. The ContentControl would >>>>>>> eventually >>>>>>> be replaced with something that would maybe do a transition when the >>>>>>> content changed.
>>>>>>> I know some things need a little home-brew TLC in SL (ie Commanding), >>>>>>> but I am left wondering if I'm applying the pattern incorrectly >>>>>>> and/or >>>>>>> not leveraging the SL framework. So far, to me, making controls on a >>>>>>> lower level makes a lot of sense, but gluing them together at a >>>>>>> higher >>>>>>> level is where my understanding of how to implement MVVM in SL falls >>>>>>> apart.
>>>>>>> -Jer
>>>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>>>> <corradocava...@gmail.com> wrote:
>>>>>>> Hi Jeremiah,
>>>>>>> Are you trying to implement a sort of Login page then, after >>>>>>> authentication, do you want to 'move' to main page?
>>>>>>> Corrado
>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>> Morrill >>>>>>> Sent: sabato 29 novembre 2008 05:39 >>>>>>> To: wpf-disciples@googlegroups.com >>>>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if >>>>>>> any >>>>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>>>> So essentially I have a ViewModel such as this:
>>>>>>> public class MainLayoutViewModel : ViewModelBase >>>>>>> { >>>>>>> private LoginViewModel m_loginController = new >>>>>>> LoginViewModel(); >>>>>>> private TestViewModel m_testController = new TestViewModel(); >>>>>>> private ViewModelBase m_currentViewModel;
>>>>>>> public ViewModelBase CurrentViewModel >>>>>>> { >>>>>>> get { return m_currentViewModel; } >>>>>>> set >>>>>>> { >>>>>>> m_currentViewModel = value; >>>>>>> InvokePropertyChanged("CurrentViewModel"); >>>>>>> } >>>>>>> } >>>>>>> }
>>>>>>> Now when my LoginViewModell "authenticates", I suppose I want to >>>>>>> change >>>>>>> the "CurrentViewModel" property to a new view model. In my View, I >>>>>>> would like to change the DataTemplate "View" to the matching >>>>>>> ViewModel, >>>>>>> but it seems something like this is not supported in SL. I found >>>>>>> some >>>>>>> great support for this in the SL Extensions <http://slextensions.net
>>>>>>> (ResourceSelector), but I was wondering how
On Sat, Nov 29, 2008 at 10:59 PM, Paul Stovell <stov...@gmail.com> wrote: > The same guy who also removed:
> - Triggers > - Element binding > - Relative source binding > - TypeDecriptors > - Dependency property inheritance > - Template binding to attached DP's > - Ability to subscribe to Changed events on DP's
> But they gave us a DataGrid, so it's OK :)
> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
>> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on >> that one?
>> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >>> event triggers, but you can't define your own routed events. Not sure that >>> can be implemented without some home-brew infrastructure. This SL Extension >>> library has the makings of a routed event framework, but I have yet to try >>> it on.
>>> -Jer
>>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>>> I don't know if this trick will work in Silverlight but one technique I >>>> used in WPF was to have a Control as a place holder and used a trigger to >>>> change the template (and thus contents) of the control based on what object >>>> I wanted to display. I used it similar to your "Zoo" scenario, where there >>>> were multiple classes of objects that I wanted to perform the same operation >>>> upon. I never wrote about the technique because I wasn't sure if it >>>> qualified as very useful or not. But since it seems someone else can use it, >>>> I can give a quick post about it.
>>>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >>>> jeremiah.morr...@gmail.com> wrote:
>>>>> I was looking for validation of my approach...I'd hate to have to >>>>> unlearn anything ;). All the MVVM SL examples I've looked at, have a single >>>>> "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>>>> databound to a collection of VMs. I have not seen an MVVM example showing >>>>> how to dynamically change specific controls in the View *from* the >>>>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>>>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>>>> it surely didn't look as clean as a WPF MVVM.
>>>>> My main concern, was that life seemed good with a 3rd party >>>>> solution...which makes me sometimes think I'm not leveraging the framework >>>>> I'm using correctly. And also wondering how anyone else does stuff like >>>>> this within their own applications.
>>>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>>>> -Jer
>>>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>>>>> Nice usage of "diaremail"...though I don't think your reply qualifies >>>>>> as one. :)
>>>>>> There are two pieces to this puzzle, imo. One piece decides *what*to show, the other piece decides >>>>>> *how* to show it. I think the first piece is properly handled in the >>>>>> ViewModel, as you suggested. The second piece should be handled as a >>>>>> platform-level service, like typed DataTemplates in WPF. However, as you >>>>>> pointed out, since SL doesn't have this, I think using an extension class is >>>>>> ideal.
>>>>>> What you're describing makes sense to me. What exactly is the problem >>>>>> that you are concerned about?
>>>>>> Josh
>>>>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>>>>> jeremiah.morr...@gmail.com> wrote:
>>>>>>> Thanks guys. This surely answers my question on moving from the >>>>>>> LoginView to AnotherView. But does this navigation method work well on all >>>>>>> levels of the UI?
>>>>>>> For an example, say I had a LionView, TigerView and BearView (all >>>>>>> with their complimentary ViewModels). Now visualize a stereotypical LOB >>>>>>> "Page", with a handful of controls (ie product lists, datagrids). Say one >>>>>>> of these controls was a 200x200 containing 3 buttons. Let's call it the >>>>>>> ZooView. When any of these 3 buttons are clicked, it would load up a >>>>>>> "LionView", "TigerView" and so on, within the ZooView. Of course in this >>>>>>> situation I wouldn't want to navigate to a whole new "RootVisual", just >>>>>>> "navigate" one control to another.
>>>>>>> This is all really trivial, but I feel like I "break" the MVVM >>>>>>> pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM >>>>>>> monstrosity. There's no DataType property on the DataTemplate in SL, so the >>>>>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>>>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>>>>> given ViewModel.
>>>>>>> Hope this email wasn't a diaremail =P
>>>>>>> -Jer
>>>>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>>>>> <laur...@galasoft.ch> wrote:
>>>>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>>>>> based >>>>>>>> navigation. I put "Page" in quotes because it's actually a >>>>>>>> UserControl, but >>>>>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>>>>> There are >>>>>>>> even frameworks implementing this (see
>>>>>>>> Another advantage of having the App taking care of the navigation is >>>>>>>> that it >>>>>>>> is able to read query string parameters or even the parameters >>>>>>>> entered in >>>>>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>>>>> implement.
>>>>>>>> Cheers, >>>>>>>> Laurent
>>>>>>>> -----Original Message----- >>>>>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>>>>> wpf-disciples@googlegroups.com] >>>>>>>> On Behalf Of Corrado Cavalli >>>>>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>> Think you're in wrong direction, you have to change rootvisual >>>>>>>> content, >>>>>>>> my application uses a navigation system based on this blog and it >>>>>>>> works >>>>>>>> great!
>>>>>>>> In my case, I changed the logic a bit because, after login only the >>>>>>>> internal area has to change based on navigation but approach is >>>>>>>> exactly >>>>>>>> the same
>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>> Morrill >>>>>>>> Sent: sabato 29 novembre 2008 10:57 >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>> Yeah, specifically here, that's exactly what I'm trying to >>>>>>>> accomplish. >>>>>>>> Generally, I want be able to "replace one control with another", and >>>>>>>> of >>>>>>>> course stick close to being MVVM. The ContentControl would >>>>>>>> eventually >>>>>>>> be replaced with something that would maybe do a transition when the >>>>>>>> content changed.
>>>>>>>> I know some things need a little home-brew TLC in SL (ie >>>>>>>> Commanding), >>>>>>>> but I am left wondering if I'm applying the pattern incorrectly >>>>>>>> and/or >>>>>>>> not leveraging the SL framework. So far, to me, making controls on >>>>>>>> a >>>>>>>> lower level makes a lot of sense, but gluing them together at a >>>>>>>> higher >>>>>>>> level is where my understanding of how to implement MVVM in SL falls >>>>>>>> apart.
>>>>>>>> -Jer
>>>>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>>>>> <corradocava...@gmail.com> wrote:
>>>>>>>> Hi Jeremiah,
>>>>>>>> Are you trying to implement a sort of Login page then, after >>>>>>>> authentication, do you want to 'move' to main page?
>>>>>>>> Corrado
>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>> Morrill >>>>>>>> Sent: sabato 29 novembre 2008 05:39 >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if >>>>>>>> any >>>>>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>>>>> So essentially I have a ViewModel such as this:
>>>>>>>> public class MainLayoutViewModel : ViewModelBase >>>>>>>> { >>>>>>>> private LoginViewModel m_loginController = new >>>>>>>> LoginViewModel(); >>>>>>>> private TestViewModel m_testController = new TestViewModel(); >>>>>>>> private ViewModelBase m_currentViewModel;
>>>>>>>> public ViewModelBase CurrentViewModel >>>>>>>> { >>>>>>>> get { return m_currentViewModel; } >>>>>>>> set >>>>>>>> { >>>>>>>> m_currentViewModel = value; >>>>>>>> InvokePropertyChanged("CurrentViewModel"); >>>>>>>> } >>>>>>>> } >>>>>>>> }
>>>>>>>> Now when my LoginViewModell "authenticates", I suppose I want to >>>>>>>> change >>>>>>>> the "CurrentViewModel" property to a new view model. In my View, I
Whomever, "that guy" is...He's a brave one. It takes a lot of guts to remove all those and laugh at the thought of rabid developers hunting him/her down. ;)
I still feel there's *a lot* of bang for the *buck* in SL. Even with my initial frustrations, I was able to talk myself off the ledge by chanting "At least its not ActionScript...At least its not ActionScript...". =P
On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote: > The same guy who also removed:
> - Triggers > - Element binding > - Relative source binding > - TypeDecriptors > - Dependency property inheritance > - Template binding to attached DP's > - Ability to subscribe to Changed events on DP's
> But they gave us a DataGrid, so it's OK :)
> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
>> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on >> that one?
>> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >>> event triggers, but you can't define your own routed events. Not sure that >>> can be implemented without some home-brew infrastructure. This SL Extension >>> library has the makings of a routed event framework, but I have yet to try >>> it on.
>>> -Jer
>>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>>> I don't know if this trick will work in Silverlight but one technique I >>>> used in WPF was to have a Control as a place holder and used a trigger to >>>> change the template (and thus contents) of the control based on what object >>>> I wanted to display. I used it similar to your "Zoo" scenario, where there >>>> were multiple classes of objects that I wanted to perform the same operation >>>> upon. I never wrote about the technique because I wasn't sure if it >>>> qualified as very useful or not. But since it seems someone else can use it, >>>> I can give a quick post about it.
>>>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >>>> jeremiah.morr...@gmail.com> wrote:
>>>>> I was looking for validation of my approach...I'd hate to have to >>>>> unlearn anything ;). All the MVVM SL examples I've looked at, have a single >>>>> "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>>>> databound to a collection of VMs. I have not seen an MVVM example showing >>>>> how to dynamically change specific controls in the View *from* the >>>>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>>>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>>>> it surely didn't look as clean as a WPF MVVM.
>>>>> My main concern, was that life seemed good with a 3rd party >>>>> solution...which makes me sometimes think I'm not leveraging the framework >>>>> I'm using correctly. And also wondering how anyone else does stuff like >>>>> this within their own applications.
>>>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>>>> -Jer
>>>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>>>>> Nice usage of "diaremail"...though I don't think your reply qualifies >>>>>> as one. :)
>>>>>> There are two pieces to this puzzle, imo. One piece decides *what*to show, the other piece decides >>>>>> *how* to show it. I think the first piece is properly handled in the >>>>>> ViewModel, as you suggested. The second piece should be handled as a >>>>>> platform-level service, like typed DataTemplates in WPF. However, as you >>>>>> pointed out, since SL doesn't have this, I think using an extension class is >>>>>> ideal.
>>>>>> What you're describing makes sense to me. What exactly is the problem >>>>>> that you are concerned about?
>>>>>> Josh
>>>>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>>>>> jeremiah.morr...@gmail.com> wrote:
>>>>>>> Thanks guys. This surely answers my question on moving from the >>>>>>> LoginView to AnotherView. But does this navigation method work well on all >>>>>>> levels of the UI?
>>>>>>> For an example, say I had a LionView, TigerView and BearView (all >>>>>>> with their complimentary ViewModels). Now visualize a stereotypical LOB >>>>>>> "Page", with a handful of controls (ie product lists, datagrids). Say one >>>>>>> of these controls was a 200x200 containing 3 buttons. Let's call it the >>>>>>> ZooView. When any of these 3 buttons are clicked, it would load up a >>>>>>> "LionView", "TigerView" and so on, within the ZooView. Of course in this >>>>>>> situation I wouldn't want to navigate to a whole new "RootVisual", just >>>>>>> "navigate" one control to another.
>>>>>>> This is all really trivial, but I feel like I "break" the MVVM >>>>>>> pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM >>>>>>> monstrosity. There's no DataType property on the DataTemplate in SL, so the >>>>>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>>>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>>>>> given ViewModel.
>>>>>>> Hope this email wasn't a diaremail =P
>>>>>>> -Jer
>>>>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>>>>> <laur...@galasoft.ch> wrote:
>>>>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>>>>> based >>>>>>>> navigation. I put "Page" in quotes because it's actually a >>>>>>>> UserControl, but >>>>>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>>>>> There are >>>>>>>> even frameworks implementing this (see
>>>>>>>> Another advantage of having the App taking care of the navigation is >>>>>>>> that it >>>>>>>> is able to read query string parameters or even the parameters >>>>>>>> entered in >>>>>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>>>>> implement.
>>>>>>>> Cheers, >>>>>>>> Laurent
>>>>>>>> -----Original Message----- >>>>>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>>>>> wpf-disciples@googlegroups.com] >>>>>>>> On Behalf Of Corrado Cavalli >>>>>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>> Think you're in wrong direction, you have to change rootvisual >>>>>>>> content, >>>>>>>> my application uses a navigation system based on this blog and it >>>>>>>> works >>>>>>>> great!
>>>>>>>> In my case, I changed the logic a bit because, after login only the >>>>>>>> internal area has to change based on navigation but approach is >>>>>>>> exactly >>>>>>>> the same
>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>> Morrill >>>>>>>> Sent: sabato 29 novembre 2008 10:57 >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>> Yeah, specifically here, that's exactly what I'm trying to >>>>>>>> accomplish. >>>>>>>> Generally, I want be able to "replace one control with another", and >>>>>>>> of >>>>>>>> course stick close to being MVVM. The ContentControl would >>>>>>>> eventually >>>>>>>> be replaced with something that would maybe do a transition when the >>>>>>>> content changed.
>>>>>>>> I know some things need a little home-brew TLC in SL (ie >>>>>>>> Commanding), >>>>>>>> but I am left wondering if I'm applying the pattern incorrectly >>>>>>>> and/or >>>>>>>> not leveraging the SL framework. So far, to me, making controls on >>>>>>>> a >>>>>>>> lower level makes a lot of sense, but gluing them together at a >>>>>>>> higher >>>>>>>> level is where my understanding of how to implement MVVM in SL falls >>>>>>>> apart.
>>>>>>>> -Jer
>>>>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>>>>> <corradocava...@gmail.com> wrote:
>>>>>>>> Hi Jeremiah,
>>>>>>>> Are you trying to implement a sort of Login page then, after >>>>>>>> authentication, do you want to 'move' to main page?
>>>>>>>> Corrado
>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>> Morrill >>>>>>>> Sent: sabato 29 novembre 2008 05:39 >>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if >>>>>>>> any >>>>>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>>>>> So essentially I have a ViewModel such as this:
>>>>>>>> public class MainLayoutViewModel : ViewModelBase >>>>>>>> { >>>>>>>> private LoginViewModel m_loginController = new >>>>>>>> LoginViewModel(); >>>>>>>> private TestViewModel m_testController = new TestViewModel(); >>>>>>>> private ViewModelBase m_currentViewModel;
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Paul Stovell Sent: domenica 30 novembre 2008 04:59 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
The same guy who also removed:
* Triggers * Element binding * Relative source binding * TypeDecriptors * Dependency property inheritance * Template binding to attached DP's * Ability to subscribe to Changed events on DP's
But they gave us a DataGrid, so it's OK :)
On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on that one?
I think triggers are pretty limited in SL 2.0. AFAIK, there are only event triggers, but you can't define your own routed events. Not sure that can be implemented without some home-brew infrastructure. This SL Extension library has the makings of a routed event framework, but I have yet to try it on.
-Jer
On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
I don't know if this trick will work in Silverlight but one technique I used in WPF was to have a Control as a place holder and used a trigger to change the template (and thus contents) of the control based on what object I wanted to display. I used it similar to your "Zoo" scenario, where there were multiple classes of objects that I wanted to perform the same operation upon. I never wrote about the technique because I wasn't sure if it qualified as very useful or not. But since it seems someone else can use it, I can give a quick post about it.
I was looking for validation of my approach...I'd hate to have to unlearn anything ;). All the MVVM SL examples I've looked at, have a single "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be databound to a collection of VMs. I have not seen an MVVM example showing how to dynamically change specific controls in the View *from* the ViewModel. I was starting to clutter my View's codebehind to handle a lot of that, so thats why I said it started being like the MVP/MVVM hybrid...and it surely didn't look as clean as a WPF MVVM.
My main concern, was that life seemed good with a 3rd party solution...which makes me sometimes think I'm not leveraging the framework I'm using correctly. And also wondering how anyone else does stuff like this within their own applications.
Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
-Jer
On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> wrote:
Nice usage of "diaremail"...though I don't think your reply qualifies as one. :)
There are two pieces to this puzzle, imo. One piece decides what to show, the other piece decides how to show it. I think the first piece is properly handled in the ViewModel, as you suggested. The second piece should be handled as a platform-level service, like typed DataTemplates in WPF. However, as you pointed out, since SL doesn't have this, I think using an extension class is ideal.
What you're describing makes sense to me. What exactly is the problem that you are concerned about?
Thanks guys. This surely answers my question on moving from the LoginView to AnotherView. But does this navigation method work well on all levels of the UI?
For an example, say I had a LionView, TigerView and BearView (all with their complimentary ViewModels). Now visualize a stereotypical LOB "Page", with a handful of controls (ie product lists, datagrids). Say one of these controls was a 200x200 containing 3 buttons. Let's call it the ZooView. When any of these 3 buttons are clicked, it would load up a "LionView", "TigerView" and so on, within the ZooView. Of course in this situation I wouldn't want to navigate to a whole new "RootVisual", just "navigate" one control to another.
This is all really trivial, but I feel like I "break" the MVVM pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's no DataType property on the DataTemplate in SL, so the ResourceSelector from the SL extensions lib seems to fill the gap in making the SL View more intelligent as to what DataTemplate (or View) to use with a given ViewModel.
Hope this email wasn't a diaremail =P
-Jer
On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP]
I am with Corrado on that one. The idea in Silverlight is a "Page" based navigation. I put "Page" in quotes because it's actually a UserControl, but still, the idea is heavily inspired from WPF's navigation service. There are even frameworks implementing this (see http://blogs.telerik.com/BoryanaMiloshevska/Posts/08-10-03/Page_Navig... or_Silverlight_2_RC0.aspx for instance).
Another advantage of having the App taking care of the navigation is that it is able to read query string parameters or even the parameters entered in the "object" tag, and so a bookmarked navigation is also easy to implement.
On Behalf Of Corrado Cavalli Sent: Saturday, November 29, 2008 11:45 AM To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Think you're in wrong direction, you have to change rootvisual content, my application uses a navigation system based on this blog and it works great!
In my case, I changed the logic a bit because, after login only the internal area has to change based on navigation but approach is exactly the same
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 10:57 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Yeah, specifically here, that's exactly what I'm trying to accomplish. Generally, I want be able to "replace one control with another", and of course stick close to being MVVM. The ContentControl would eventually be replaced with something that would maybe do a transition when the content changed.
I know some things need a little home-brew TLC in SL (ie Commanding), but I am left wondering if I'm applying the pattern incorrectly and/or not leveraging the SL framework. So far, to me, making controls on a lower level makes a lot of sense, but gluing them together at a higher level is where my understanding of how to implement MVVM in SL falls apart.
-Jer
On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli <corradocava...@gmail.com> wrote:
Hi Jeremiah,
Are you trying to implement a sort of Login page then, after authentication, do you want to 'move' to main page?
Corrado
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 05:39 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Silverlight + MVVM = More questions
I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some
(ResourceSelector), but I was wondering how everyone else does this, or if there is a better way or if I'm just doin' it wrong? My View with the SL extension looks like this:
jeremiah.morr...@gmail.com> wrote: > Whomever, "that guy" is...He's a brave one. It takes a lot of guts to > remove all those and laugh at the thought of rabid developers hunting > him/her down. ;)
> I still feel there's *a lot* of bang for the *buck* in SL. Even with my > initial frustrations, I was able to talk myself off the ledge by chanting > "At least its not ActionScript...At least its not ActionScript...". =P
> -Jer > On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote:
>> The same guy who also removed:
>> - Triggers >> - Element binding >> - Relative source binding >> - TypeDecriptors >> - Dependency property inheritance >> - Template binding to attached DP's >> - Ability to subscribe to Changed events on DP's
>> But they gave us a DataGrid, so it's OK :)
>> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on >>> that one?
>>> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >>>> event triggers, but you can't define your own routed events. Not sure that >>>> can be implemented without some home-brew infrastructure. This SL Extension >>>> library has the makings of a routed event framework, but I have yet to try >>>> it on.
>>>> -Jer
>>>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>>>> I don't know if this trick will work in Silverlight but one technique I >>>>> used in WPF was to have a Control as a place holder and used a trigger to >>>>> change the template (and thus contents) of the control based on what object >>>>> I wanted to display. I used it similar to your "Zoo" scenario, where there >>>>> were multiple classes of objects that I wanted to perform the same operation >>>>> upon. I never wrote about the technique because I wasn't sure if it >>>>> qualified as very useful or not. But since it seems someone else can use it, >>>>> I can give a quick post about it.
>>>>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >>>>> jeremiah.morr...@gmail.com> wrote:
>>>>>> I was looking for validation of my approach...I'd hate to have to >>>>>> unlearn anything ;). All the MVVM SL examples I've looked at, have a single >>>>>> "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>>>>> databound to a collection of VMs. I have not seen an MVVM example showing >>>>>> how to dynamically change specific controls in the View *from* the >>>>>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>>>>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>>>>> it surely didn't look as clean as a WPF MVVM.
>>>>>> My main concern, was that life seemed good with a 3rd party >>>>>> solution...which makes me sometimes think I'm not leveraging the framework >>>>>> I'm using correctly. And also wondering how anyone else does stuff like >>>>>> this within their own applications.
>>>>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>>>>> -Jer
>>>>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com>wrote:
>>>>>>> Nice usage of "diaremail"...though I don't think your reply qualifies >>>>>>> as one. :)
>>>>>>> There are two pieces to this puzzle, imo. One piece decides *what*to show, the other piece decides >>>>>>> *how* to show it. I think the first piece is properly handled in >>>>>>> the ViewModel, as you suggested. The second piece should be handled as a >>>>>>> platform-level service, like typed DataTemplates in WPF. However, as you >>>>>>> pointed out, since SL doesn't have this, I think using an extension class is >>>>>>> ideal.
>>>>>>> What you're describing makes sense to me. What exactly is the >>>>>>> problem that you are concerned about?
>>>>>>> Josh
>>>>>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>>>>>> jeremiah.morr...@gmail.com> wrote:
>>>>>>>> Thanks guys. This surely answers my question on moving from the >>>>>>>> LoginView to AnotherView. But does this navigation method work well on all >>>>>>>> levels of the UI?
>>>>>>>> For an example, say I had a LionView, TigerView and BearView (all >>>>>>>> with their complimentary ViewModels). Now visualize a stereotypical LOB >>>>>>>> "Page", with a handful of controls (ie product lists, datagrids). Say one >>>>>>>> of these controls was a 200x200 containing 3 buttons. Let's call it the >>>>>>>> ZooView. When any of these 3 buttons are clicked, it would load up a >>>>>>>> "LionView", "TigerView" and so on, within the ZooView. Of course in this >>>>>>>> situation I wouldn't want to navigate to a whole new "RootVisual", just >>>>>>>> "navigate" one control to another.
>>>>>>>> This is all really trivial, but I feel like I "break" the MVVM >>>>>>>> pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM >>>>>>>> monstrosity. There's no DataType property on the DataTemplate in SL, so the >>>>>>>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>>>>>>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>>>>>>> given ViewModel.
>>>>>>>> Hope this email wasn't a diaremail =P
>>>>>>>> -Jer
>>>>>>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>>>>>>> <laur...@galasoft.ch> wrote:
>>>>>>>>> I am with Corrado on that one. The idea in Silverlight is a "Page" >>>>>>>>> based >>>>>>>>> navigation. I put "Page" in quotes because it's actually a >>>>>>>>> UserControl, but >>>>>>>>> still, the idea is heavily inspired from WPF's navigation service. >>>>>>>>> There are >>>>>>>>> even frameworks implementing this (see
>>>>>>>>> Another advantage of having the App taking care of the navigation >>>>>>>>> is that it >>>>>>>>> is able to read query string parameters or even the parameters >>>>>>>>> entered in >>>>>>>>> the "object" tag, and so a bookmarked navigation is also easy to >>>>>>>>> implement.
>>>>>>>>> Cheers, >>>>>>>>> Laurent
>>>>>>>>> -----Original Message----- >>>>>>>>> From: wpf-disciples@googlegroups.com [mailto: >>>>>>>>> wpf-disciples@googlegroups.com] >>>>>>>>> On Behalf Of Corrado Cavalli >>>>>>>>> Sent: Saturday, November 29, 2008 11:45 AM >>>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>>> Think you're in wrong direction, you have to change rootvisual >>>>>>>>> content, >>>>>>>>> my application uses a navigation system based on this blog and it >>>>>>>>> works >>>>>>>>> great!
>>>>>>>>> In my case, I changed the logic a bit because, after login only the >>>>>>>>> internal area has to change based on navigation but approach is >>>>>>>>> exactly >>>>>>>>> the same
>>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>>> Morrill >>>>>>>>> Sent: sabato 29 novembre 2008 10:57 >>>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>>>>>>>> Yeah, specifically here, that's exactly what I'm trying to >>>>>>>>> accomplish. >>>>>>>>> Generally, I want be able to "replace one control with another", >>>>>>>>> and of >>>>>>>>> course stick close to being MVVM. The ContentControl would >>>>>>>>> eventually >>>>>>>>> be replaced with something that would maybe do a transition when >>>>>>>>> the >>>>>>>>> content changed.
>>>>>>>>> I know some things need a little home-brew TLC in SL (ie >>>>>>>>> Commanding), >>>>>>>>> but I am left wondering if I'm applying the pattern incorrectly >>>>>>>>> and/or >>>>>>>>> not leveraging the SL framework. So far, to me, making controls on >>>>>>>>> a >>>>>>>>> lower level makes a lot of sense, but gluing them together at a >>>>>>>>> higher >>>>>>>>> level is where my understanding of how to implement MVVM in SL >>>>>>>>> falls >>>>>>>>> apart.
>>>>>>>>> -Jer
>>>>>>>>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >>>>>>>>> <corradocava...@gmail.com> wrote:
>>>>>>>>> Hi Jeremiah,
>>>>>>>>> Are you trying to implement a sort of Login page then, after >>>>>>>>> authentication, do you want to 'move' to main page?
>>>>>>>>> Corrado
>>>>>>>>> From: wpf-disciples@googlegroups.com >>>>>>>>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah >>>>>>>>> Morrill >>>>>>>>> Sent: sabato 29 novembre 2008 05:39 >>>>>>>>> To: wpf-disciples@googlegroups.com >>>>>>>>> Subject: [WPF Disciples] Silverlight + MVVM = More questions
>>>>>>>>> I'm still trying to grok, as they say, MVVM in Silverlight. So if >>>>>>>>> any >>>>>>>>> of this sounds ignorant, don't be shy about letting me know.
>>>>>>>>> So essentially I have a ViewModel such as this:
>>>>>>>>> public class MainLayoutViewModel : ViewModelBase >>>>>>>>> { >>>>>>>>> private
I am sworn to secrecy ;) but there is a lot in store for Silverlight 3. Patience, grasshoppers, patience.
For the records, the story of triggers in SL is as follows:
. Triggers are apparently really hard to implement, and the team had to give up.
. They implemented VSM instead
. Then they saw that VSM was actually pretty cool
. So now VSM is going to flow into WPF.
. Triggers *should* go into SL some day too, but I wouldn't hold my breath
The only event trigger that is "supported" is the Loaded event, which is nothing more than a remain from the past (SL1) and so it is recommended not to use it. I usually prefer to trigger the animations in code.
At least, it's not ActionScript ;)
Laurent
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Marlon Grech Sent: Sunday, November 30, 2008 8:50 AM To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
they say Silverlight is the little brother of WPF.... apparently from a different father....
Whomever, "that guy" is...He's a brave one. It takes a lot of guts to remove all those and laugh at the thought of rabid developers hunting him/her down. ;)
I still feel there's a lot of bang for the buck in SL. Even with my initial frustrations, I was able to talk myself off the ledge by chanting "At least its not ActionScript...At least its not ActionScript...". =P
-Jer
On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote:
The same guy who also removed:
* Triggers * Element binding * Relative source binding * TypeDecriptors * Dependency property inheritance * Template binding to attached DP's * Ability to subscribe to Changed events on DP's
But they gave us a DataGrid, so it's OK :)
On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on that one?
I think triggers are pretty limited in SL 2.0. AFAIK, there are only event triggers, but you can't define your own routed events. Not sure that can be implemented without some home-brew infrastructure. This SL Extension library has the makings of a routed event framework, but I have yet to try it on.
-Jer
On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
I don't know if this trick will work in Silverlight but one technique I used in WPF was to have a Control as a place holder and used a trigger to change the template (and thus contents) of the control based on what object I wanted to display. I used it similar to your "Zoo" scenario, where there were multiple classes of objects that I wanted to perform the same operation upon. I never wrote about the technique because I wasn't sure if it qualified as very useful or not. But since it seems someone else can use it, I can give a quick post about it.
I was looking for validation of my approach...I'd hate to have to unlearn anything ;). All the MVVM SL examples I've looked at, have a single "Page" with a VM and maybe an ItemsControl/Panel or ListBox, that would be databound to a collection of VMs. I have not seen an MVVM example showing how to dynamically change specific controls in the View *from* the ViewModel. I was starting to clutter my View's codebehind to handle a lot of that, so thats why I said it started being like the MVP/MVVM hybrid...and it surely didn't look as clean as a WPF MVVM.
My main concern, was that life seemed good with a 3rd party solution...which makes me sometimes think I'm not leveraging the framework I'm using correctly. And also wondering how anyone else does stuff like this within their own applications.
Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
-Jer
On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> wrote:
Nice usage of "diaremail"...though I don't think your reply qualifies as one. :)
There are two pieces to this puzzle, imo. One piece decides what to show, the other piece decides how to show it. I think the first piece is properly handled in the ViewModel, as you suggested. The second piece should be handled as a platform-level service, like typed DataTemplates in WPF. However, as you pointed out, since SL doesn't have this, I think using an extension class is ideal.
What you're describing makes sense to me. What exactly is the problem that you are concerned about?
Thanks guys. This surely answers my question on moving from the LoginView to AnotherView. But does this navigation method work well on all levels of the UI?
For an example, say I had a LionView, TigerView and BearView (all with their complimentary ViewModels). Now visualize a stereotypical LOB "Page", with a handful of controls (ie product lists, datagrids). Say one of these controls was a 200x200 containing 3 buttons. Let's call it the ZooView. When any of these 3 buttons are clicked, it would load up a "LionView", "TigerView" and so on, within the ZooView. Of course in this situation I wouldn't want to navigate to a whole new "RootVisual", just "navigate" one control to another.
This is all really trivial, but I feel like I "break" the MVVM pattern and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's no DataType property on the DataTemplate in SL, so the ResourceSelector from the SL extensions lib seems to fill the gap in making the SL View more intelligent as to what DataTemplate (or View) to use with a given ViewModel.
Hope this email wasn't a diaremail =P
-Jer
On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP]
I am with Corrado on that one. The idea in Silverlight is a "Page" based navigation. I put "Page" in quotes because it's actually a UserControl, but still, the idea is heavily inspired from WPF's navigation service. There are even frameworks implementing this (see http://blogs.telerik.com/BoryanaMiloshevska/Posts/08-10-03/Page_Navig... or_Silverlight_2_RC0.aspx for instance).
Another advantage of having the App taking care of the navigation is that it is able to read query string parameters or even the parameters entered in the "object" tag, and so a bookmarked navigation is also easy to implement.
On Behalf Of Corrado Cavalli Sent: Saturday, November 29, 2008 11:45 AM To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Think you're in wrong direction, you have to change rootvisual content, my application uses a navigation system based on this blog and it works great!
In my case, I changed the logic a bit because, after login only the internal area has to change based on navigation but approach is exactly the same
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 10:57 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
Yeah, specifically here, that's exactly what I'm trying to accomplish. Generally, I want be able to "replace one control with another", and of course stick close to being MVVM. The ContentControl would eventually be replaced with something that would maybe do a transition when the content changed.
I know some things need a little home-brew TLC in SL (ie Commanding), but I am left wondering if I'm applying the pattern incorrectly and/or not leveraging the SL framework. So far, to me, making controls on a lower level makes a lot of sense, but gluing them together at a higher level is where my understanding of how to implement MVVM in SL falls apart.
-Jer
On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli <corradocava...@gmail.com> wrote:
Hi Jeremiah,
Are you trying to implement a sort of Login page then, after authentication, do you want to 'move' to main page?
Corrado
From: wpf-disciples@googlegroups.com [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill Sent: sabato 29 novembre 2008 05:39 To: wpf-disciples@googlegroups.com Subject: [WPF Disciples] Silverlight + MVVM = More questions
I'm still trying to grok, as they say, MVVM in Silverlight. So if any of this sounds ignorant, don't be shy about letting me know.
So essentially I have a ViewModel such as this:
public class MainLayoutViewModel : ViewModelBase { private LoginViewModel m_loginController = new LoginViewModel(); private TestViewModel m_testController = new TestViewModel(); private ViewModelBase m_currentViewModel;
public MainLayoutViewModel() { CurrentViewModel = m_loginController; }
public ViewModelBase CurrentViewModel { get { return m_currentViewModel; } set { m_currentViewModel = value; InvokePropertyChanged("CurrentViewModel"); } } }
Now when my LoginViewModell "authenticates", I suppose I want to change the "CurrentViewModel" property to a new view model. In my View, I would like to change the DataTemplate "View" to the matching ViewModel, but it seems something like this is not supported in SL. I found some
<laur...@galasoft.ch> wrote: > I am sworn to secrecy ;) but there is a lot in store for Silverlight 3. > Patience, grasshoppers, patience…
> For the records, the story of triggers in SL is as follows:
> · Triggers are apparently really hard to implement, and the team > had to give up.
> · They implemented VSM instead
> · Then they saw that VSM was actually pretty cool
> · So now VSM is going to flow into WPF.
> · Triggers *should* go into SL some day too, but I wouldn't hold > my breath
> The only event trigger that is "supported" is the Loaded event, which is > nothing more than a remain from the past (SL1) and so it is recommended not > to use it. I usually prefer to trigger the animations in code.
> At least, it's not ActionScript ;)
> Laurent
> *From:* wpf-disciples@googlegroups.com [mailto: > wpf-disciples@googlegroups.com] *On Behalf Of *Marlon Grech > *Sent:* Sunday, November 30, 2008 8:50 AM
> they say Silverlight is the little brother of WPF.... apparently from a > different father....
> On Sun, Nov 30, 2008 at 5:29 AM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
> Whomever, "that guy" is...He's a brave one. It takes a lot of guts to > remove all those and laugh at the thought of rabid developers hunting > him/her down. ;)
> I still feel there's *a lot* of bang for the *buck* in SL. Even with my > initial frustrations, I was able to talk myself off the ledge by chanting > "At least its not ActionScript...At least its not ActionScript...". =P
> -Jer
> On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote:
> The same guy who also removed:
> - Triggers > - Element binding > - Relative source binding > - TypeDecriptors > - Dependency property inheritance > - Template binding to attached DP's > - Ability to subscribe to Changed events on DP's
> But they gave us a DataGrid, so it's OK :)
> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on > that one?
> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
> I think triggers are pretty limited in SL 2.0. AFAIK, there are only event > triggers, but you can't define your own routed events. Not sure that can be > implemented without some home-brew infrastructure. This SL Extension > library has the makings of a routed event framework, but I have yet to try > it on.
> -Jer
> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
> I don't know if this trick will work in Silverlight but one technique I > used in WPF was to have a Control as a place holder and used a trigger to > change the template (and thus contents) of the control based on what object > I wanted to display. I used it similar to your "Zoo" scenario, where there > were multiple classes of objects that I wanted to perform the same operation > upon. I never wrote about the technique because I wasn't sure if it > qualified as very useful or not. But since it seems someone else can use it, > I can give a quick post about it.
> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
> I was looking for validation of my approach...I'd hate to have to unlearn > anything ;). All the MVVM SL examples I've looked at, have a single "Page" > with a VM and maybe an ItemsControl/Panel or ListBox, that would be > databound to a collection of VMs. I have not seen an MVVM example showing > how to dynamically change specific controls in the View *from* the > ViewModel. I was starting to clutter my View's codebehind to handle a lot > of that, so thats why I said it started being like the MVP/MVVM hybrid...and > it surely didn't look as clean as a WPF MVVM.
> My main concern, was that life seemed good with a 3rd party > solution...which makes me sometimes think I'm not leveraging the framework > I'm using correctly. And also wondering how anyone else does stuff like > this within their own applications.
> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
> -Jer
> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> > wrote:
> Nice usage of "diaremail"...though I don't think your reply qualifies as > one. :)
> There are two pieces to this puzzle, imo. One piece decides *what* to > show, the other piece decides *how* to show it. I think the first piece > is properly handled in the ViewModel, as you suggested. The second piece > should be handled as a platform-level service, like typed DataTemplates in > WPF. However, as you pointed out, since SL doesn't have this, I think using > an extension class is ideal.
> What you're describing makes sense to me. What exactly is the problem that > you are concerned about?
> Josh
> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < > jeremiah.morr...@gmail.com> wrote:
> Thanks guys. This surely answers my question on moving from the LoginView > to AnotherView. But does this navigation method work well on all levels of > the UI?
> For an example, say I had a LionView, TigerView and BearView (all with > their complimentary ViewModels). Now visualize a stereotypical LOB "Page", > with a handful of controls (ie product lists, datagrids). Say one of these > controls was a 200x200 containing 3 buttons. Let's call it the ZooView. > When any of these 3 buttons are clicked, it would load up a "LionView", > "TigerView" and so on, within the ZooView. Of course in this situation I > wouldn't want to navigate to a whole new "RootVisual", just "navigate" one > control to another.
> This is all really trivial, but I feel like I "break" the MVVM pattern and > it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's > no DataType property on the DataTemplate in SL, so the ResourceSelector from > the SL extensions lib seems to fill the gap in making the SL View more > intelligent as to what DataTemplate (or View) to use with a given ViewModel.
> Hope this email wasn't a diaremail =P
> -Jer
> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] > <laur...@galasoft.ch> wrote:
> I am with Corrado on that one. The idea in Silverlight is a "Page" based > navigation. I put "Page" in quotes because it's actually a UserControl, but > still, the idea is heavily inspired from WPF's navigation service. There > are > even frameworks implementing this (see
> Another advantage of having the App taking care of the navigation is that > it > is able to read query string parameters or even the parameters entered in > the "object" tag, and so a bookmarked navigation is also easy to implement.
> On Behalf Of Corrado Cavalli > Sent: Saturday, November 29, 2008 11:45 AM > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
> Think you're in wrong direction, you have to change rootvisual content, > my application uses a navigation system based on this blog and it works > great!
> In my case, I changed the logic a bit because, after login only the > internal area has to change based on navigation but approach is exactly > the same
> From: wpf-disciples@googlegroups.com > [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill > Sent: sabato 29 novembre 2008 10:57 > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
> Yeah, specifically here, that's exactly what I'm trying to accomplish. > Generally, I want be able to "replace one control with another", and of > course stick close to being MVVM. The ContentControl would eventually > be replaced with something that would maybe do a transition when the > content changed.
> I know some things need a little home-brew TLC in SL (ie Commanding), > but I am left wondering if I'm applying the pattern incorrectly and/or > not leveraging the SL framework. So far, to me, making controls on a > lower level makes a lot of sense, but gluing them together at a higher > level is where my understanding of how to implement MVVM in SL falls > apart.
> -Jer
> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli > <corradocava...@gmail.com> wrote:
> Hi Jeremiah,
> Are you trying to implement a sort of Login page then, after > authentication, do you want to 'move' to main page?
> Corrado
> From: wpf-disciples@googlegroups.com > [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill > Sent: sabato 29 novembre 2008 05:39 > To: wpf-disciples@googlegroups.com > Subject: [WPF Disciples] Silverlight + MVVM = More questions
> I'm still trying to grok, as they say, MVVM in Silverlight. So if any > of this sounds ignorant, don't be shy about letting me know.
> So essentially I have a ViewModel such as this:
> public class MainLayoutViewModel : ViewModelBase > { > private LoginViewModel m_loginController = new LoginViewModel(); > private TestViewModel m_testController = new TestViewModel(); > private ViewModelBase m_currentViewModel;
WPF was designed and implemented as a core, no-compromise Windows component. In order to get a small, portable, factored implementation of WPF that would work the same on Windows and non-Windows including Mobile devices that don't even run the CLR, we reimplemented much of the framework. We will be adding other WPF features as time goes on. I wrote about some of the harder choices here:
On Sun, Nov 30, 2008 at 8:39 AM, Mike Brown <mbrow...@gmail.com> wrote: > Okay...I guess I have to bite the bullet...
> On Sun, Nov 30, 2008 at 7:08 AM, Laurent Bugnion, GalaSoft [MVP] > <laur...@galasoft.ch> wrote:
>> I am sworn to secrecy ;) but there is a lot in store for Silverlight 3. >> Patience, grasshoppers, patience…
>> For the records, the story of triggers in SL is as follows:
>> · Triggers are apparently really hard to implement, and the team >> had to give up.
>> · They implemented VSM instead
>> · Then they saw that VSM was actually pretty cool
>> · So now VSM is going to flow into WPF.
>> · Triggers *should* go into SL some day too, but I wouldn't hold >> my breath
>> The only event trigger that is "supported" is the Loaded event, which is >> nothing more than a remain from the past (SL1) and so it is recommended not >> to use it. I usually prefer to trigger the animations in code.
>> At least, it's not ActionScript ;)
>> Laurent
>> *From:* wpf-disciples@googlegroups.com [mailto: >> wpf-disciples@googlegroups.com] *On Behalf Of *Marlon Grech >> *Sent:* Sunday, November 30, 2008 8:50 AM
>> they say Silverlight is the little brother of WPF.... apparently from a >> different father....
>> On Sun, Nov 30, 2008 at 5:29 AM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>> Whomever, "that guy" is...He's a brave one. It takes a lot of guts to >> remove all those and laugh at the thought of rabid developers hunting >> him/her down. ;)
>> I still feel there's *a lot* of bang for the *buck* in SL. Even with my >> initial frustrations, I was able to talk myself off the ledge by chanting >> "At least its not ActionScript...At least its not ActionScript...". =P
>> -Jer
>> On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote:
>> The same guy who also removed:
>> - Triggers >> - Element binding >> - Relative source binding >> - TypeDecriptors >> - Dependency property inheritance >> - Template binding to attached DP's >> - Ability to subscribe to Changed events on DP's
>> But they gave us a DataGrid, so it's OK :)
>> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> wrote:
>> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on >> that one?
>> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >> event triggers, but you can't define your own routed events. Not sure that >> can be implemented without some home-brew infrastructure. This SL Extension >> library has the makings of a routed event framework, but I have yet to try >> it on.
>> -Jer
>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>> I don't know if this trick will work in Silverlight but one technique I >> used in WPF was to have a Control as a place holder and used a trigger to >> change the template (and thus contents) of the control based on what object >> I wanted to display. I used it similar to your "Zoo" scenario, where there >> were multiple classes of objects that I wanted to perform the same operation >> upon. I never wrote about the technique because I wasn't sure if it >> qualified as very useful or not. But since it seems someone else can use it, >> I can give a quick post about it.
>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>> I was looking for validation of my approach...I'd hate to have to unlearn >> anything ;). All the MVVM SL examples I've looked at, have a single "Page" >> with a VM and maybe an ItemsControl/Panel or ListBox, that would be >> databound to a collection of VMs. I have not seen an MVVM example showing >> how to dynamically change specific controls in the View *from* the >> ViewModel. I was starting to clutter my View's codebehind to handle a lot >> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >> it surely didn't look as clean as a WPF MVVM.
>> My main concern, was that life seemed good with a 3rd party >> solution...which makes me sometimes think I'm not leveraging the framework >> I'm using correctly. And also wondering how anyone else does stuff like >> this within their own applications.
>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>> -Jer
>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> >> wrote:
>> Nice usage of "diaremail"...though I don't think your reply qualifies as >> one. :)
>> There are two pieces to this puzzle, imo. One piece decides *what* to >> show, the other piece decides *how* to show it. I think the first piece >> is properly handled in the ViewModel, as you suggested. The second piece >> should be handled as a platform-level service, like typed DataTemplates in >> WPF. However, as you pointed out, since SL doesn't have this, I think using >> an extension class is ideal.
>> What you're describing makes sense to me. What exactly is the problem >> that you are concerned about?
>> Josh
>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >> jeremiah.morr...@gmail.com> wrote:
>> Thanks guys. This surely answers my question on moving from the LoginView >> to AnotherView. But does this navigation method work well on all levels of >> the UI?
>> For an example, say I had a LionView, TigerView and BearView (all with >> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >> with a handful of controls (ie product lists, datagrids). Say one of these >> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >> When any of these 3 buttons are clicked, it would load up a "LionView", >> "TigerView" and so on, within the ZooView. Of course in this situation I >> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >> control to another.
>> This is all really trivial, but I feel like I "break" the MVVM pattern and >> it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. There's >> no DataType property on the DataTemplate in SL, so the ResourceSelector from >> the SL extensions lib seems to fill the gap in making the SL View more >> intelligent as to what DataTemplate (or View) to use with a given ViewModel.
>> Hope this email wasn't a diaremail =P
>> -Jer
>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >> <laur...@galasoft.ch> wrote:
>> I am with Corrado on that one. The idea in Silverlight is a "Page" based >> navigation. I put "Page" in quotes because it's actually a UserControl, >> but >> still, the idea is heavily inspired from WPF's navigation service. There >> are >> even frameworks implementing this (see
>> Another advantage of having the App taking care of the navigation is that >> it >> is able to read query string parameters or even the parameters entered in >> the "object" tag, and so a bookmarked navigation is also easy to >> implement.
>> On Behalf Of Corrado Cavalli >> Sent: Saturday, November 29, 2008 11:45 AM >> To: wpf-disciples@googlegroups.com >> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>> Think you're in wrong direction, you have to change rootvisual content, >> my application uses a navigation system based on this blog and it works >> great!
>> In my case, I changed the logic a bit because, after login only the >> internal area has to change based on navigation but approach is exactly >> the same
>> From: wpf-disciples@googlegroups.com >> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >> Sent: sabato 29 novembre 2008 10:57 >> To: wpf-disciples@googlegroups.com >> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >> Generally, I want be able to "replace one control with another", and of >> course stick close to being MVVM. The ContentControl would eventually >> be replaced with something that would maybe do a transition when the >> content changed.
>> I know some things need a little home-brew TLC in SL (ie Commanding), >> but I am left wondering if I'm applying the pattern incorrectly and/or >> not leveraging the SL framework. So far, to me, making controls on a >> lower level makes a lot of sense, but gluing them together at a higher >> level is where my understanding of how to implement MVVM in SL falls >> apart.
>> -Jer
>> On Fri, Nov 28, 2008 at 9:25 PM, Corrado Cavalli >> <corradocava...@gmail.com> wrote:
>> Hi Jeremiah,
>> Are you trying to implement a sort of Login page then, after
To be honest, I understand fully the sacrifices and decisions that needed to be made with Silverlight. When I said bite the bullet, I meant I had put off learning VSM for a while. I'm going to stop procrastinating and spend a good weekend with SL2U. To be fully honest, I'd prefer to see 3D before triggers...if the VSM supports a workaround then I'm all for it!
On Sun, Nov 30, 2008 at 3:43 PM, John Gossman <gossmans...@gmail.com> wrote: > WPF was designed and implemented as a core, no-compromise Windows > component. In order to get a small, portable, factored implementation of > WPF that would work the same on Windows and non-Windows including Mobile > devices that don't even run the CLR, we reimplemented much of the > framework. We will be adding other WPF features as time goes on. I wrote > about some of the harder choices here:
> On Sun, Nov 30, 2008 at 8:39 AM, Mike Brown <mbrow...@gmail.com> wrote:
>> Okay...I guess I have to bite the bullet...
>> On Sun, Nov 30, 2008 at 7:08 AM, Laurent Bugnion, GalaSoft [MVP] >> <laur...@galasoft.ch> wrote:
>>> I am sworn to secrecy ;) but there is a lot in store for Silverlight 3. >>> Patience, grasshoppers, patience…
>>> For the records, the story of triggers in SL is as follows:
>>> · Triggers are apparently really hard to implement, and the team >>> had to give up.
>>> · They implemented VSM instead
>>> · Then they saw that VSM was actually pretty cool
>>> · So now VSM is going to flow into WPF.
>>> · Triggers *should* go into SL some day too, but I wouldn't hold >>> my breath
>>> The only event trigger that is "supported" is the Loaded event, which is >>> nothing more than a remain from the past (SL1) and so it is recommended not >>> to use it. I usually prefer to trigger the animations in code.
>>> At least, it's not ActionScript ;)
>>> Laurent
>>> *From:* wpf-disciples@googlegroups.com [mailto: >>> wpf-disciples@googlegroups.com] *On Behalf Of *Marlon Grech >>> *Sent:* Sunday, November 30, 2008 8:50 AM
>>> they say Silverlight is the little brother of WPF.... apparently from a >>> different father....
>>> On Sun, Nov 30, 2008 at 5:29 AM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>> Whomever, "that guy" is...He's a brave one. It takes a lot of guts to >>> remove all those and laugh at the thought of rabid developers hunting >>> him/her down. ;)
>>> I still feel there's *a lot* of bang for the *buck* in SL. Even with my >>> initial frustrations, I was able to talk myself off the ledge by chanting >>> "At least its not ActionScript...At least its not ActionScript...". =P
>>> -Jer
>>> On Sat, Nov 29, 2008 at 7:59 PM, Paul Stovell <stov...@gmail.com> wrote:
>>> The same guy who also removed:
>>> - Triggers >>> - Element binding >>> - Relative source binding >>> - TypeDecriptors >>> - Dependency property inheritance >>> - Template binding to attached DP's >>> - Ability to subscribe to Changed events on DP's
>>> But they gave us a DataGrid, so it's OK :)
>>> On Sun, Nov 30, 2008 at 12:19 PM, Mike Brown <mbrow...@gmail.com> >>> wrote:
>>> So there are no DataTriggers in Silverlight? WTF! Who dropped the ball on >>> that one?
>>> On Sat, Nov 29, 2008 at 9:14 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>> I think triggers are pretty limited in SL 2.0. AFAIK, there are only >>> event triggers, but you can't define your own routed events. Not sure that >>> can be implemented without some home-brew infrastructure. This SL Extension >>> library has the makings of a routed event framework, but I have yet to try >>> it on.
>>> -Jer
>>> On Sat, Nov 29, 2008 at 5:58 PM, Mike Brown <mbrow...@gmail.com> wrote:
>>> I don't know if this trick will work in Silverlight but one technique I >>> used in WPF was to have a Control as a place holder and used a trigger to >>> change the template (and thus contents) of the control based on what object >>> I wanted to display. I used it similar to your "Zoo" scenario, where there >>> were multiple classes of objects that I wanted to perform the same operation >>> upon. I never wrote about the technique because I wasn't sure if it >>> qualified as very useful or not. But since it seems someone else can use it, >>> I can give a quick post about it.
>>> On Sat, Nov 29, 2008 at 6:34 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>> I was looking for validation of my approach...I'd hate to have to unlearn >>> anything ;). All the MVVM SL examples I've looked at, have a single "Page" >>> with a VM and maybe an ItemsControl/Panel or ListBox, that would be >>> databound to a collection of VMs. I have not seen an MVVM example showing >>> how to dynamically change specific controls in the View *from* the >>> ViewModel. I was starting to clutter my View's codebehind to handle a lot >>> of that, so thats why I said it started being like the MVP/MVVM hybrid...and >>> it surely didn't look as clean as a WPF MVVM.
>>> My main concern, was that life seemed good with a 3rd party >>> solution...which makes me sometimes think I'm not leveraging the framework >>> I'm using correctly. And also wondering how anyone else does stuff like >>> this within their own applications.
>>> Thanks all...I feel like I'm well on my way to MVVM nirvana in SL.
>>> -Jer
>>> On Sat, Nov 29, 2008 at 1:57 PM, Josh Smith <flappleja...@gmail.com> >>> wrote:
>>> Nice usage of "diaremail"...though I don't think your reply qualifies as >>> one. :)
>>> There are two pieces to this puzzle, imo. One piece decides *what* to >>> show, the other piece decides *how* to show it. I think the first piece >>> is properly handled in the ViewModel, as you suggested. The second piece >>> should be handled as a platform-level service, like typed DataTemplates in >>> WPF. However, as you pointed out, since SL doesn't have this, I think using >>> an extension class is ideal.
>>> What you're describing makes sense to me. What exactly is the problem >>> that you are concerned about?
>>> Josh
>>> On Sat, Nov 29, 2008 at 3:50 PM, Jeremiah Morrill < >>> jeremiah.morr...@gmail.com> wrote:
>>> Thanks guys. This surely answers my question on moving from the >>> LoginView to AnotherView. But does this navigation method work well on all >>> levels of the UI?
>>> For an example, say I had a LionView, TigerView and BearView (all with >>> their complimentary ViewModels). Now visualize a stereotypical LOB "Page", >>> with a handful of controls (ie product lists, datagrids). Say one of these >>> controls was a 200x200 containing 3 buttons. Let's call it the ZooView. >>> When any of these 3 buttons are clicked, it would load up a "LionView", >>> "TigerView" and so on, within the ZooView. Of course in this situation I >>> wouldn't want to navigate to a whole new "RootVisual", just "navigate" one >>> control to another.
>>> This is all really trivial, but I feel like I "break" the MVVM pattern >>> and it mutates into some crazy ModelViewPresenter-ish-MVVM monstrosity. >>> There's no DataType property on the DataTemplate in SL, so the >>> ResourceSelector from the SL extensions lib seems to fill the gap in making >>> the SL View more intelligent as to what DataTemplate (or View) to use with a >>> given ViewModel.
>>> Hope this email wasn't a diaremail =P
>>> -Jer
>>> On Sat, Nov 29, 2008 at 4:33 AM, Laurent Bugnion, GalaSoft [MVP] >>> <laur...@galasoft.ch> wrote:
>>> I am with Corrado on that one. The idea in Silverlight is a "Page" based >>> navigation. I put "Page" in quotes because it's actually a UserControl, >>> but >>> still, the idea is heavily inspired from WPF's navigation service. There >>> are >>> even frameworks implementing this (see
>>> Another advantage of having the App taking care of the navigation is that >>> it >>> is able to read query string parameters or even the parameters entered in >>> the "object" tag, and so a bookmarked navigation is also easy to >>> implement.
>>> On Behalf Of Corrado Cavalli >>> Sent: Saturday, November 29, 2008 11:45 AM >>> To: wpf-disciples@googlegroups.com >>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>> Think you're in wrong direction, you have to change rootvisual content, >>> my application uses a navigation system based on this blog and it works >>> great!
>>> In my case, I changed the logic a bit because, after login only the >>> internal area has to change based on navigation but approach is exactly >>> the same
>>> From: wpf-disciples@googlegroups.com >>> [mailto:wpf-disciples@googlegroups.com] On Behalf Of Jeremiah Morrill >>> Sent: sabato 29 novembre 2008 10:57 >>> To: wpf-disciples@googlegroups.com >>> Subject: [WPF Disciples] Re: Silverlight + MVVM = More questions
>>> Yeah, specifically here, that's exactly what I'm trying to accomplish. >>> Generally, I want be able to "replace one control with another", and of >>> course stick close to being MVVM. The ContentControl would eventually >>> be replaced with
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