Re: capture keycode in valuefield

[Bruce Steers <bsteers4@xxxxxxxxx>]

On Tue, 18 Jun 2024 at 01:18, Bruce Steers <bsteers4@xxxxxxxxx> wrote:

>
>
> On Tue, 18 Jun 2024 at 00:42, Bruce Steers <bsteers4@xxxxxxxxx> wrote:
>
>>
>>
>> On Tue, 18 Jun 2024 at 00:11, Dag JNJ <gambas@xxxxxxxxxxxx> wrote:
>>
>>> Hi,
>>>
>>> I wanted to jump between fields in the GUI using Enter, Return, Down-
>>> and Up-Arrows. In textbox-fields it. it works, like this:
>>>
>>>
>>>
>>>
>>>
>>>
>>> *Public Sub FLD_vorgabe_tbx_KeyPress()   If Key.Code = Key.Enter Or
>>> Key.Code = Key.Return Or Key.Code = Key.Down Then
>>> FLD_kommentar_tba.SetFocus   If Key.Code = Key.Up Then
>>> FLD_nachkomma_vbx.SetFocus End*
>>>
>>> All 4 keys are captured. But in a valuebox field only enter and return
>>> are captured.
>>>
>>>
>>>
>>>
>>>
>>>
>>> *Public Sub FLD_nachkomma_vbx_KeyPress()   If Key.Code = Key.Enter Or
>>> Key.Code = Key.Return Or Key.Code = Key.Down Then FLD_vorgabe_tbx.SetFocus
>>>   If Key.Code = Key.Up Then FLD_laenge_vbx.SetFocus End*
>>>
>>> Do I make something wrong, or are the capturing of arrow-keys left out
>>> for some reason? (I tried with other keys too, none seem to work).
>>>
>>> Thankful for any hint, kind regards, Dag
>>>
>>
>> I found only up and down arrow keys get swallowed and do not fire the
>> event but left and right keys do.
>>
>> I wonder if there is code to make up and down keys adjust the value but
>> it is not working?
>> For whatever the reason up and down key events seem to be eaten by the
>> control.
>> The wiki does explain that some non-native controls can swallow key
>> events, this is one of those cases.
>>
>> Respects
>> BruceS
>>
>
>
> You can do this simple override (i think it works okay and does not effect
> the ValueBox workings)..
> you will have an intercept for Key events before the ValueBox sees them
> and if in the FMain.class you Stop the ValueBox_KeyPress event the
> ValueBox should not see it.......
>
> Save the following text as a file called ValueBox.class in your projects
> .src folder
>
> -------------snip----------------
> ' Gambas class file  ValueBox.class
>
> Export
> Event KeyPress
>
> Public Sub NumberBox_KeyPress()
>
>   Dim bStop As Boolean
>   bStop = Raise KeyPress
>   If bStop Then
>     Stop Event
>     Return
>   Endif
>
>   Super.NumberBox_KeyPress  ' this line may not be needed
>
> End
> --------------snip-------------
>
> That allows you things like this in FMain...
>
> Public Sub ValueBox1_KeyPress()
>
>   If Key.code = Key.Up Then
>     Inc ValueBox1.Value
>     Stop Event
>   Else If Key.code = Key.Down Then
>     Dec ValueBox1.Value
>     Stop Event
>   Endif
>
> End
>
> Respects
> BruceS
>

I have had a similar issue a few times with a few different controls where
i wanted to handle/see all the key events before the control did and had to
find a workaround for it as by default there was no way.
It would be good i think if all controls had something like a
Control.KeyPressFirst property so ANY Control / UserControl that has that
set will use the above bStop type syntax to raise the KeyPress event first
so you can see ALL Key events before the control gets the chance to eat it
and also you can Stop the control seeing it if you want.

Respects
BruceS