Listview - keep a selection when clicking a subitem ?
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R.Wieser
Oct 1, 2022, 6:45:18 AM10/1/22
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Hello all,
I've created a listview with a few columns which allows multiple rows to be
selected.
The thing is that I would like to be able to select a few rows and than
click subitems without loosing that selection.
I've been looking if I could ignore the LVN_SELECTIONCHANGED notification,
but that one doesn't even return a value. And as the NM_CLICK notification
comes in after all the changes its not usable either.
tl;dr:
Does anyone know how to keep a set of rows selected when clicking a subitem
?
Or maybe the other way around : can I limit the selection of rows to only
when clicking the main item row ?
Regards,
Rudy Wieser
I've created a listview with a few columns which allows multiple rows to be
selected.
The thing is that I would like to be able to select a few rows and than
click subitems without loosing that selection.
I've been looking if I could ignore the LVN_SELECTIONCHANGED notification,
but that one doesn't even return a value. And as the NM_CLICK notification
comes in after all the changes its not usable either.
tl;dr:
Does anyone know how to keep a set of rows selected when clicking a subitem
?
Or maybe the other way around : can I limit the selection of rows to only
when clicking the main item row ?
Regards,
Rudy Wieser
JJ
Oct 1, 2022, 10:16:51 AM10/1/22
to
R.Wieser
Oct 1, 2022, 2:38:53 PM10/1/22
to
JJ,
> Hold CTRL key for selecting more items without deselecting existing
> item(s).
I know, thats not the problem. I have the need to be able to click
subitems (no ctrl or shift held) *without* the selection mechanism kicking
in.
And by the way: Have you ever tried to ctrl-click items and than click a
subitem ? The selection for that row will toggle ...
Hmm.... I just checked, for a reference, what OE6 does in such a case
(trying to set the 'ignore' state for a set of rows). The other selected
rows and the last (ctrl-selected) one do not change status at the same
moment - due to that last row getting its selection toggeled when again
ctrl-clicked.
.... and that might mean that I set my goal a bit to high ....
Regards,
Rudy Wieser
> Hold CTRL key for selecting more items without deselecting existing
> item(s).
subitems (no ctrl or shift held) *without* the selection mechanism kicking
in.
And by the way: Have you ever tried to ctrl-click items and than click a
subitem ? The selection for that row will toggle ...
Hmm.... I just checked, for a reference, what OE6 does in such a case
(trying to set the 'ignore' state for a set of rows). The other selected
rows and the last (ctrl-selected) one do not change status at the same
moment - due to that last row getting its selection toggeled when again
ctrl-clicked.
.... and that might mean that I set my goal a bit to high ....
Regards,
Rudy Wieser
R.Wieser
Oct 2, 2022, 4:41:49 AM10/2/22
to
JJ,
> Hold CTRL key for selecting more items without deselecting existing
> item(s).
I forgot to explicitily mention that I'm using the listview in LVS_REPORT
style.
Something "funny" :
Using a basic listview (no LVS_EX_FULLROWSELECT) you *cannot* select rows
other than by clicking on the main items column, but clicking /anywhere/ on
a row *will* drop the (carefull) selection you made. Go figure ...
There might be a reason for doing it that way, but I'm not yet been able to
figure it out.
Regards,
Rudy Wieser
> Hold CTRL key for selecting more items without deselecting existing
> item(s).
style.
Something "funny" :
Using a basic listview (no LVS_EX_FULLROWSELECT) you *cannot* select rows
other than by clicking on the main items column, but clicking /anywhere/ on
a row *will* drop the (carefull) selection you made. Go figure ...
There might be a reason for doing it that way, but I'm not yet been able to
figure it out.
Regards,
Rudy Wieser
JJ
Oct 2, 2022, 8:31:29 AM10/2/22
to
On Sun, 2 Oct 2022 10:41:37 +0200, R.Wieser wrote:
>
> I forgot to explicitily mention that I'm using the listview in LVS_REPORT
> style.
>
> Something "funny" :
>
> Using a basic listview (no LVS_EX_FULLROWSELECT) you *cannot* select rows
> other than by clicking on the main items column, but clicking /anywhere/ on
> a row *will* drop the (carefull) selection you made. Go figure ...
>
> There might be a reason for doing it that way, but I'm not yet been able to
> figure it out.
>
> Regards,
> Rudy Wieser
Might want to try injecting CTRL key event at the correct time. e.g. when
>
> I forgot to explicitily mention that I'm using the listview in LVS_REPORT
> style.
>
> Something "funny" :
>
> Using a basic listview (no LVS_EX_FULLROWSELECT) you *cannot* select rows
> other than by clicking on the main items column, but clicking /anywhere/ on
> a row *will* drop the (carefull) selection you made. Go figure ...
>
> There might be a reason for doing it that way, but I'm not yet been able to
> figure it out.
>
> Regards,
> Rudy Wieser
mouse enters the ListView and when there's existing selection.
R.Wieser
Oct 2, 2022, 11:48:24 AM10/2/22
to
JJ,
> Might want to try injecting CTRL key event at the correct time.
> e.g. when mouse enters the ListView and when there's existing
> selection.
I'm afraid that the/my problem already shows itself when doing the first
selection and than clicking a subitem column (to effect a change al-la OE6
with its "ignore" (spectacle icon) column). I'm confident it will do the
same on a second selection (without my mouse having left the listview
controls window).
Another "funny" one : Select a few rows (using shift-click) and than do a
ctrl-click afterwards (selecting a new or deselecting a currently selected
row). After that there is no way to click anywhere (on a subitem or
otherwise) to effect a change without either loosing the selection
(shift-click) or unselecting the row you click (ctrl-click) and having to
click it again to select it again. Fun when you want to toggle something
in all of those rows ...
I already tried to fight the selection mechanism by capturing
LVN_ITEMCHANGING and in certain cases disallowing a change*, but than
strange stuff started to happen when I continued ctrl-clicking rows.
* a problem in itself, 'cause multiple changes (selected, focussed) can
occur at the same time, and it seems to be an all-or-nothing rejection.
Currently I've chosen to ignore, in the listviews NM_CLICK notification
code, the ctrl/shift click on a subitem if its done on an (just switched to)
unselected row. It makes sure that if a change is made its made on all rows
at the same time.
... I might include a check to see if the clicked row is the only one
selected, and than effect a non-ctrl/shift click too.
I must say, I really enjoy working with those basic, freely configurable
controls. /s
Regards,
Rudy Wieser
> Might want to try injecting CTRL key event at the correct time.
> e.g. when mouse enters the ListView and when there's existing
> selection.
selection and than clicking a subitem column (to effect a change al-la OE6
with its "ignore" (spectacle icon) column). I'm confident it will do the
same on a second selection (without my mouse having left the listview
controls window).
Another "funny" one : Select a few rows (using shift-click) and than do a
ctrl-click afterwards (selecting a new or deselecting a currently selected
row). After that there is no way to click anywhere (on a subitem or
otherwise) to effect a change without either loosing the selection
(shift-click) or unselecting the row you click (ctrl-click) and having to
click it again to select it again. Fun when you want to toggle something
in all of those rows ...
I already tried to fight the selection mechanism by capturing
LVN_ITEMCHANGING and in certain cases disallowing a change*, but than
strange stuff started to happen when I continued ctrl-clicking rows.
* a problem in itself, 'cause multiple changes (selected, focussed) can
occur at the same time, and it seems to be an all-or-nothing rejection.
Currently I've chosen to ignore, in the listviews NM_CLICK notification
code, the ctrl/shift click on a subitem if its done on an (just switched to)
unselected row. It makes sure that if a change is made its made on all rows
at the same time.
... I might include a check to see if the clicked row is the only one
selected, and than effect a non-ctrl/shift click too.
I must say, I really enjoy working with those basic, freely configurable
controls. /s
Regards,
Rudy Wieser
Paul N
Oct 18, 2022, 9:31:32 AM10/18/22
to
R.Wieser
Oct 19, 2022, 4:52:57 AM10/19/22
to
Paul,
> Would it be possible to subclass the control and intercept that message?
At some point I was considering the same. Up until the point I realized I
would be fighting the build-in selection method, and could only hope it
would not get out on sync or have wierd side effects (i've tried some other
build-in(!) stuff which did just that).
Next to that I still needed the click event so I could do my own thing.
That means I would either had to move code from outside the listview to
inside it, of fake my own notification.
In the end I decided that especially the fighting was not worth it, and
setteled on not executing my own code when a subitem was clicked and (as a
result) was just deselected.
Thanks for the suggestion though.
Regards,
Rudy Wieser
> Would it be possible to subclass the control and intercept that message?
would be fighting the build-in selection method, and could only hope it
would not get out on sync or have wierd side effects (i've tried some other
build-in(!) stuff which did just that).
Next to that I still needed the click event so I could do my own thing.
That means I would either had to move code from outside the listview to
inside it, of fake my own notification.
In the end I decided that especially the fighting was not worth it, and
setteled on not executing my own code when a subitem was clicked and (as a
result) was just deselected.
Thanks for the suggestion though.
Regards,
Rudy Wieser
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