MATLAB CTL-C GUI Cleanup

Hello, I have created a GUI to collect some data. This GUI uses some equipment that has to be connected/disconnected to MATLAB with commands. I want to make it so that when you push CTL-C to stop running something any of the functions, the equipment is disconnected properly. Is that possible without using "oncleanup" with putting it in every function used in the GUI?

Answer 1

[Walter Roberson]

When you launch the GUI, have a function create an oncleanup, and then have the function uiwait() or waitfor() the gui figure. The control-C will trigger exiting the uiwait() or waitfor(), causing the function to exit, triggering the oncleanup .

... at least in theory.

[Sarah Crimi]

Honestly I still don't understand this answer. I made a function to check to see if the equipment is turned off that turns off the equipment if necessary. However, I have no idea where to call that function. I can't find a sort of function matlab created to close the GUI. The only thing that I can think is to create a button that does this. But this doesn't account for 'CTL-C' cases or cases where GUI is closed with red x button that is already on GUI.

[Walter Roberson]

See https://www.mathworks.com/help/matlab/ref/matlab.ui.figure-properties.html#buiwuyk-1-CloseRequestFcn for controlling what happens when the figure closes including by clicking on the "X" window decoration.

If you are using GUIDE then look in the *OpeningFcn callback that gets created for your GUI. You will see a pair of lines like

% UIWAIT makes MyGUI wait for user response (see UIRESUME)
% uiwait(handles.figure1);

Before those lines, put in a onCleanup call. Then, remove the comment marker from the second line, so it would look like

% UIWAIT makes MyGUI wait for user response (see UIRESUME)
uiwait(handles.figure1);

That will cause MATLAB to not return to the command prompt: instead it will wait for the figure to be closed or for control-C . When either of those happens then the *OpeningFcn would exit, triggering the onCleanup action.

[Sarah Crimi]

Ok, I tried this. It gives me an error though when I press 'CTL-C'

Warning: The following error was caught while executing 'onCleanup' class destructor:
Not enough input arguments. 
> In MyGUI>MyGUI_OpeningFcn (line 60)
  In gui_mainfcn (line 220)
  In MyGUI (line 43) 
Operation terminated by user during uiwait (line 81)

In MyGUI>MyGUI_OpeningFcn (line 82)
uiwait(handles.figure1);

[Walter Roberson]

Hmmm, https://www.mathworks.com/matlabcentral/answers/156803-detection-of-ctrl-c-in-m-file suggests using onCleanup, which agrees with my memory, and when I test the code there it works. But I agree that the onCleanup does not seem to get invoked for ^C for waitfor() or uiwait() so I do not know what the solution is.

[Sarah Crimi]

thanks for your help :)