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GUI: how to call callback function from keyboard using 'windowkeypressfcn'?

Asked by James Ang on 18 Apr 2015
Latest activity Commented on by James Ang on 19 Apr 2015
Hi all,
I've pushbutton callback function as below:
function movefront_Callback(hObject, eventdata, handles)
handles.speed.String = num2str(str2double(handles.speed.String) +1);
And I would like to call this function from the keyboard, so I've this:
function figure1_WindowKeyPressFcn(hObject, eventdata, handles)
switch eventdata.Key
case 'a'
handles.speed.String = num2str(str2double(handles.speed.String) + 1);
case 'b'
handles.speed.String = num2str(str2double(handles.speed.String) - 1);
end
The above code works but I called it directly from the handles structure. How do I call the callback function from the windowskeypress function?
e.g
switch eventdata.Key
case 'a'
@movefront_Callback(); %not working obviously
thanks in advance.

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1 Answer

Answer by Geoff Hayes
on 18 Apr 2015
 Accepted Answer

James - all you need to do is to just call the callback directly and ensure that you pass the correct inputs. Since your callback signature is
function movefront_Callback(hObject, eventdata, handles)
then you need to pass the handle to the movefront control (this is hObject), the event data (which can be empty as it seems to be only valid for key presses and other events like that) and the handles structure. So your key press callback can become
function figure1_WindowKeyPressFcn(hObject, eventdata, handles)
switch eventdata.Key
case 'a'
movefront_Callback(handles.movefront, [], handles);
case 'b'
moveback_Callback(handles.moveback, [], handles);
end
Try the above and see what happens!

  1 Comment

It works! thank you Geoff! =D

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