> On Mon, Mar 15, 2010 at 9:18 PM, Sacha Barber <sacha.bar...@gmail.com>wrote:

>> I prefer option 1 actually

>> On Mon, Mar 15, 2010 at 8:43 PM, Marlon Grech <marlongr...@gmail.com>wrote:

>>> P.S sorry for ugly code and all that but the code I produced is just to
>>> show you guys the idea ....

>>> Regards
>>> Marlon
>>> WPF Blog - http://marlongrech.wordpress.com/
>>> Microsoft MVP for Client App

>>>   On Mon, Mar 15, 2010 at 8:42 PM, Marlon Grech <marlongr...@gmail.com>wrote:

>>>> Attached is take 2...

>>>> Basically I hate it when my ViewModel has to implement all these
>>>> interfaces... It feels like back in Java days to me...

>>>> so the idea here is to still use namescopes but leverage the databinding
>>>> capabilities of WPF... so that you can do something like this

>>>> <Grid focusStuff:FocusedBehaviourTake2.FocusElement="{Binding Focus}">

>>>> and in the VM

>>>> Save = new RelayCommand( x => Focus= "Name");

>>>> Basically in the ViewModel you set a property that exposes the element
>>>> that should get focus. The attached behavior (which accepts binding) will
>>>> get triggered when the property changes. THERE IS ONE SIDE EFFECT OF THIS.
>>>> Basically if the viewmodel sets the Focus property to be the same the
>>>> attached behavior will not get triggered again... this might be a show
>>>> stopper for this idea... what do you guys think?

>>>> which approach would you like best?

>>>> Regards
>>>> Marlon
>>>> WPF Blog - http://marlongrech.wordpress.com/
>>>> Microsoft MVP for Client App

>>>>   On Mon, Mar 15, 2010 at 8:25 PM, Daniel Vaughan <dbvaug...@gmail.com>wrote:

>>>>> Good thinking Marlon. As Pete said, very innovative.

>>>>> On Mar 15, 7:33 pm, Marlon Grech <marlongr...@gmail.com> wrote:
>>>>> > something like this... but I need to do something else so that its
>>>>> cooler...

>>>>> > The Idea is that rather then setting an attached property to every
>>>>> element
>>>>> > you want to control you just set it once and find that element by
>>>>> using WPF
>>>>> > Namescopes.

>>>>> > Attached is a prototype... yet I just built this now... did not test
>>>>> it...
>>>>> > and probably I have bugs all over the place.,... I just did it to
>>>>> show you
>>>>> > what I mean

>>>>> > Regards
>>>>> > Marlon
>>>>> > WPF Blog -http://marlongrech.wordpress.com/
>>>>> > Microsoft MVP for Client App

>>>>> > On Mon, Mar 15, 2010 at 5:50 PM, Josh Smith <flappleja...@gmail.com>
>>>>> wrote:
>>>>> > > What do you have in mind?

>>>>> > > On Mon, Mar 15, 2010 at 10:46 AM, Marlon Grech <
>>>>> marlongr...@gmail.com>wrote:

>>>>> > >> mmm... interesting approach... what about leveraging Namescopes
>>>>> for such a
>>>>> > >> thing?

>>>>> > >> Regards
>>>>> > >> Marlon
>>>>> > >> WPF Blog -http://marlongrech.wordpress.com/
>>>>> > >> Microsoft MVP for Client App

>>>>> > >> On Mon, Mar 15, 2010 at 3:12 PM, Peter O'Hanlon <
>>>>> pete.ohan...@gmail.com>wrote:

>>>>> > >>> Sounds good. As far as the FocusScopes go, there shouldn't be any
>>>>> issues,
>>>>> > >>> but it's an edge case to consider (I've been bitten too many
>>>>> times by custom
>>>>> > >>> FocusScopes).

>>>>> > >>> On Mon, Mar 15, 2010 at 3:08 PM, Josh Smith <
>>>>> flappleja...@gmail.com>wrote:

>>>>> > >>>> Thanks Pete. I was thinking that there could be an attached
>>>>> property of
>>>>> > >>>> type bool that is set on an element, instead of setting
>>>>> ValidatedProperty.
>>>>> > >>>>  When set, that attached property figures out which property on
>>>>> the element
>>>>> > >>>> to monitor, such as Text on a TextBox.  This would make it
>>>>> easier than
>>>>> > >>>> having to specify the property, though that would still be an
>>>>> option if you
>>>>> > >>>> need to specify it.

>>>>> > >>>> I'll have to look into FocusScopes, though I don't see any
>>>>> issues there
>>>>> > >>>> (I might be overlooking something...).

>>>>> > >>>> Josh

>>>>> > >>>> On Mon, Mar 15, 2010 at 6:31 AM, Peter O'Hanlon <
>>>>> pete.ohan...@gmail.com
>>>>> > >>>> > wrote:

>>>>> > >>>>> The only thing that stands out to me is that this is going to
>>>>> have to
>>>>> > >>>>> be applied in a lot of places in a typical LOB application, so
>>>>> that might be
>>>>> > >>>>> a little bit tedious. What effects do FocusScope's have here?
>>>>> I'll need to
>>>>> > >>>>> play around with this a bit just to make sure there aren't any
>>>>> edge cases
>>>>> > >>>>> that occur (I'm primarily thinking of cases where loss of focus
>>>>> to a
>>>>> > >>>>> menu/toolbar triggers the validation but the parent FocusScope
>>>>> has changed
>>>>> > >>>>> from the textbox).

>>>>> > >>>>> Pete

>>>>> > >>>>>   On Mon, Mar 15, 2010 at 2:24 PM, Josh Smith <
>>>>> flappleja...@gmail.com>wrote:

>>>>> > >>>>>> Thanks.  Any pitfalls or gotchas sticking their heads out?

>>>>> > >>>>>> On Mon, Mar 15, 2010 at 1:03 AM, Peter O'Hanlon <
>>>>> > >>>>>> pete.ohan...@gmail.com> wrote:

>>>>> > >>>>>>> I like it - I know that it feels "dirty", but it's actually
>>>>> pretty
>>>>> > >>>>>>> darn cool.

>>>>> > >>>>>>>  On Mon, Mar 15, 2010 at 3:54 AM, Josh Smith <
>>>>> flappleja...@gmail.com
>>>>>  > >>>>>>> > wrote:

>>>>> > >>>>>>>> A while back Dr. WPF graced us with his clever hack of
>>>>> controlling
>>>>> > >>>>>>>> input focus from VM objects.  It involved hijacking the VM's
>>>>> IDataErrorInfo
>>>>> > >>>>>>>> implementation, and doing all sorts of evil-genius stuff to
>>>>> make the input
>>>>> > >>>>>>>> caret move to the correct element.  Today while I was
>>>>> *trying* to
>>>>> > >>>>>>>> read a great novel, I couldn't stop thinking about another
>>>>> way to control
>>>>> > >>>>>>>> input focus from a viewmodel object.

>>>>> > >>>>>>>> I put the novel down and did a quick spike of the idea.  The
>>>>> source
>>>>> > >>>>>>>> code is attached (rename it from .DOC to .ZIP since gmail is
>>>>> terrified of
>>>>> > >>>>>>>> ZIP files for some reason).  Here's the general idea...

>>>>> > >>>>>>>> Implement this interface on your VM class:

>>>>> > >>>>>>>>  /// <summary>
>>>>> > >>>>>>>> /// Implemented by a ViewModel that needs to control
>>>>> > >>>>>>>> /// where input focus is in a View.
>>>>> > >>>>>>>> /// </summary>
>>>>> > >>>>>>>> public interface IFocusController
>>>>> > >>>>>>>> {
>>>>> > >>>>>>>>     /// <summary>
>>>>> > >>>>>>>>     /// Raised when the input focus should move to
>>>>> > >>>>>>>>     /// a control whose 'active' dependency property
>>>>> > >>>>>>>>     /// is bound to the specified property.
>>>>> > >>>>>>>>     /// </summary>
>>>>> > >>>>>>>>     event EventHandler<MoveFocusEventArgs> MoveFocus;
>>>>> > >>>>>>>> }

>>>>> > >>>>>>>> Next, in your VM object (which might implement
>>>>> IDataErrorInfo), do
>>>>> > >>>>>>>> something like this to support a Save button:

>>>>> > >>>>>>>>  public ICommand SaveCommand
>>>>> > >>>>>>>> {
>>>>> > >>>>>>>>     get { return new RelayCommand(this.Save); }
>>>>> > >>>>>>>> }

>>>>> > >>>>>>>> void Save()
>>>>> > >>>>>>>> {
>>>>> > >>>>>>>>     if (this.HasError)
>>>>> > >>>>>>>>     {
>>>>> > >>>>>>>>         // The Error property knows which property is
>>>>> invalid.
>>>>> > >>>>>>>>         this.RaiseMoveFocus(this.Error);
>>>>> > >>>>>>>>     }
>>>>> > >>>>>>>>     else
>>>>> > >>>>>>>>     {
>>>>> > >>>>>>>>         // Save to database...
>>>>> > >>>>>>>>         System.Windows.MessageBox.Show("Saved");
>>>>> > >>>>>>>>     }
>>>>> > >>>>>>>> }

>>>>> > >>>>>>>> bool HasError
>>>>> > >>>>>>>> {
>>>>> > >>>>>>>>     get { return _validatedProperties.Any(prop =>
>>>>> > >>>>>>>> !String.IsNullOrEmpty(this[prop])); }
>>>>> > >>>>>>>> }

>>>>> > >>>>>>>>  public event EventHandler<MoveFocusEventArgs> MoveFocus;

>>>>> > >>>>>>>> void RaiseMoveFocus(string focusedProperty)
>>>>> > >>>>>>>> {
>>>>> > >>>>>>>>     var handler = this.MoveFocus;
>>>>> > >>>>>>>>     if (handler != null)
>>>>> > >>>>>>>>     {
>>>>> > >>>>>>>>         handler(this, new
>>>>> MoveFocusEventArgs(focusedProperty));
>>>>> > >>>>>>>>     }
>>>>> > >>>>>>>> }

>>>>> > >>>>>>>> Lastly, in your View, use my terribly(?) named attached
>>>>> property to
>>>>> > >>>>>>>> specify which DP on your elements is bound to the validated
>>>>> property of the
>>>>> > >>>>>>>> VM, for example:

>>>>> > >>>>>>>>  <TextBox
>>>>> > >>>>>>>>     Text="{Binding Path=FirstName,
>>>>> ValidatesOnDataErrors=True}"
>>>>> > >>>>>>>>     *local:FocusControl.ValidatedProperty="TextBox.Text"*
>>>>> > >>>>>>>>     />

>>>>> > >>>>>>>> I'm not sure that I like this approach yet.  It's a pretty
>>>>> important
>>>>> > >>>>>>>> topic, so I thought I'd share this out amongst the Disciples
>>>>> for feedback.

>>>>> > >>>>>>>> Thanks,
>>>>> > >>>>>>>> Josh

>>>>> > >>>>>>> --
>>>>> > >>>>>>> Peter O'Hanlon

>>>>> > >>>>> --
>>>>> > >>>>> Peter O'Hanlon

>>>>> > >>> --
>>>>> > >>> Peter O'Hanlon

>>>>> >  TestFocus.zip.doc
>>>>> > 140KViewDownload

>>  --
>> Sacha Barber
>> sacha.bar...@gmail.com

> --
> Peter O'Hanlon