Thread Subject: How do I give focus to a figure?

Hi,

in my application I have a large number of buttons and an
axis object in a figure. After each button press I would
like to return focus to the figure, so that key presses are
evaluated by the figure's KeyPressFcn. Is there a way to do
this programmatically?

Thanks,

Jochen Smolka

In article <fg3s2p$jgd$1@fred.mathworks.com>,
Jochen Smolka <ja511@gmx.de> wrote:

>in my application I have a large number of buttons and an
>axis object in a figure. After each button press I would
>like to return focus to the figure, so that key presses are
>evaluated by the figure's KeyPressFcn. Is there a way to do
>this programmatically?

Possibly,

set(0,'CurrentFigure',figurenumber)

This will not raise the figure like figure(figurenumber) would.


I'm not sure from your question: do you have a single figure
which contains the GUI and the axis object both? Or do you have
two figures, one with the GUI and the other one the one that
contains the axis object that you want to give control over to?
--
   So you found your solution
   What will be your last contribution?
   -- Supertramp (Fool's Overture)

Thanks for your fast reply,

both the buttons and the axis are in the same figure.
Therefore, unfortunately, neither
> set(0,'CurrentFigure',figurenumber)
nor
> figure(figurenumber)
work, because afterwards the focus (and 'CurrentObject') are
still on the recently pressed button.

I'd be grateful for any other ideas,

Jochen

"Jochen Smolka" <ja511@gmx.de> wrote in message
<fg3t05$85b$1@fred.mathworks.com>...
> Thanks for your fast reply,
>
> both the buttons and the axis are in the same figure.
> Therefore, unfortunately, neither
> > set(0,'CurrentFigure',figurenumber)
> nor
> > figure(figurenumber)
> work, because afterwards the focus (and 'CurrentObject') are
> still on the recently pressed button.
>
> I'd be grateful for any other ideas,
>
> Jochen
>


May be this will help you:

figure('keypressfcn','disp(''Key press evaluated in
figure'')') ;
h = uicontrol('style','pushbutton',...
 'string','press me', ...
 'callback','disp(''callback of button'')') ;

% (ugly) work around

set(h,'keypressfcn','eval(get(gcbf,''keypressfcn''))')


hth
Jos

"Jochen Smolka" <ja511@gmx.de> schrieb im Newsbeitrag
news:fg3s2p$jgd$1@fred.mathworks.com...
> Hi,
>
> in my application I have a large number of buttons and an
> axis object in a figure. After each button press I would
> like to return focus to the figure, so that key presses are
> evaluated by the figure's KeyPressFcn. Is there a way to do
> this programmatically?
>
> Thanks,
>
> Jochen Smolka

Hi Jochen,
unfortunately the answer is no. But there is some sort of
workaround: instead of using the callback for the button, do
the following: set the button enable property to "inactive",
and use the buttondownfcn instead of the callback. This
way the button does not get the control so the figure stays
in control...

Titus

Thanks for your replies.

As a quick feedback:
- We have tried a few similar solutions to the 'ugly' work
around, and the problem is that we are getting into trouble
when trying to determine the cursor position during a key
press in the callback. That seems to depend on the button
position.

- The second solution is quite nice, we are using that at
the moment. The only problem I could find is that by
deactivating the buttons we are also loosing the tooltips.
(We added a function now that shows the tooltip in a help
window on right mouse button press).

Thanks again to all of you,

Jochen

I tried the solution with "buttonpressfunc" on an inactive button and this was not working. I guess the "buttonpressfunc" has to be caught at the figure level. Then you must determine if the mouse position is on top of the button.

I had a callback whenever the user press a button on the main figure and this was becoming innactive after pressing the button. I thus simply made a copy of the 'keypressfcn' content from the figure to the button and it works like a charm.

Arno

figure(this.FigureHandle);
set(this.FigureHandle, 'HandleVisibility', 'on');

I have solved this problem in the past by putting a call to my main figure keyPressFcn callback in each of the keyPressFcn callbacks of my buttons, etc. on the GUI. For example, here is an example key handler for any combination of key presses in the main GUI figure:

function figure1_KeyPressFcn(hObject, eventdata, handles)

% Initialize the modifier key values
control = 0;
alt = 0;
shift = 0;

currChar = get(handles.figure1,'CurrentCharacter');
currKey = get(handles.figure1,'CurrentKey');
currMod = get(handles.figure1,'CurrentModifier');

% Determine which modifiers have been pressed
for i=1:length(currMod)
    switch(currMod{i})
        case 'control'
            control = 1;
        case 'alt'
            alt = 1;
        case 'shift'
            shift = 1;
    end
end

% Key combinations:
if control==1 && strcmp(currKey,'z') % Undo last action
    undo(hObject, eventdata, handles)
elseif control==1 && strcmp(currKey,'y') % Redo last action
    redo(hObject, eventdata, handles)
elseif strcmp(currChar,'a') % Do "a"
    pbA_Callback(hObject, eventdata, handles)
elseif strcmp(currChar,'b') % Do "a"
    pbB_Callback(hObject, eventdata, handles)
elseif strcmp(currChar,'c') % Do "a"
    pbC_Callback(hObject, eventdata, handles)
end


Then all you have to do is add the following code to each push button keyPressFcn:

function pbA_KeyPressFcn(hObject, eventdata, handles)
currChar = get(handles.figure1,'CurrentCharacter');
if ~isequal(currChar,char(13))
figure1_KeyPressFcn(hObject, eventdata, handles)
else
        pbA_Callback(hObject, eventdata, handles)
end

The char(13) check was added to allow the user to press 'enter' to evaluate the selected button callback. Otherwise, the main figure1_KeyPressFcn is evaluated to determine what to do.

Dear Jochen Smolka!

> in my application I have a large number of buttons and an
> axis object in a figure. After each button press I would
> like to return focus to the figure, so that key presses are
> evaluated by the figure's KeyPressFcn. Is there a way to do
> this programmatically?

See thread: http://www.mathworks.com/matlabcentral/newsreader/view_thread/235825

There I explained, that the following piece of code can be inserted in the callbacks of the buttons:
  set(hObject, 'Enable', 'off');
  drawnow;
  set(hObject, 'Enable', 'on');
[hObject] is the handle of the current button. Then the focus has moved to the figure again. Actually this should be performed by "figure(FigureHandle)" also, but this does not work for unknown reasons.
Unfortunately the above trick does not work for Matlab 2008a.

Good luck, Jan