Is it possible to detect when a gui moves to the background?

Hello all,

I use one main-gui for entering parameters when a sub-gui does calculations in the background.

Is it possible to detect when a gui moves to the background? And if so how do I program my sub-gui to reload variables when this happens?

An user has the ability to click on the minimize button or just click on a different gui.

When the user reopens the sub-gui I need the value’s to reset.

SimpleExample

%InputsMaingui
Ingreadients.Suger =3;
Ingreadients.flour = 1;

Open subgui
%show output:
Ingreadients.Suger =3;
Ingreadients.flour = 1;

*click on main window in the back
%change value's
Ingreadients.Suger =50;
Ingreadients.flour = 4;

*click on subgui *this is when it goes wrong and the gui uses the wrong data.
%show output
Ingreadients.Suger =3;
Ingreadients.flour = 1;

this happens cause the users dont "restart" the sub-gui so I want the sub-gui to restart everytime it has been to the background.

Or a method that forces an user to close the sub-gui before he/she can click anywere else. Like when an error message pops up you have to pres "ok" before you can continue any other operation

Regards, Nick

Answer 1

[Jan]

There is no documented method to achieve this, but an undocumented one:

FigH   = gcf;  drawnow;
jFrame = get(handle(FigH), 'JavaFrame');
% [EDITED]
try
   jProx = jFrame.fFigureClient.getWindow;
catch
   jProx = jFrame.fHG1Client.getWindow;
end
% [/EDITED]
set(jProx, 'WindowLostFocusCallback', {@figLostFocus, FigH});

function figLostFocus(jProx, EventData, FigH)
disp(clock)  % Dummy for testing

Is is recommended to set this into a TRY/CATCH-Block and simply a useful error message, when it fails. The shown method might fail in future Matlab version as all undocumented features.

[Nick]

If I try the code you typed there I get the following error:

No appropriate method, property, or field fFigureClient for class com.mathworks.hg.peer.HG1FigurePeer

Do you know a method that forces an user to close the sub-gui before he/she can click anywere else? Like when an error message pops up you have to pres "ok" before you can continue any other operation.

[Jan]

Please post which Matlab version you are using.

Do you mean:

figure('WindowStyle', 'modal')

See [EDITED] for a possibly working fallback. But remember that such errors are typical of undocumented methods.

[Nick]

I am using Matlab R2012b.

And indeed

   figure('WindowStyle', 'modal')

is the code im looking for thanks allot!