Correct Usage of uiwait and uiresume in MATLAB App Designer

I am really having confusion where to place this both commands `uiwait` and `uiresume`

I am using app designer in matlab. and I am having this GUI in the middle of the code, so for the program to stop until this GUI complete, I am using these commands.

I tried placing

`uiwait` in `app startupFcn`

function startupFcn(app)
               uiwait(app.UIFigure)
            end

And `uiresume` in

function UIFigureCloseRequest(app, event)
                uiresume(app.UIFigure)
                delete(app)
            end

But ended with errors

    `Error using getappdata Value must be a handle`

My GUI will close when I press a Button because I assigned `closereq` at the end of that Button callback function.

Let me know if any further info is needed.

Answer 1

[Ajit Kasturi]

Hi,

Go through the following resources available for uiwait and uiresume in MATLAB App Designer:

• https://blogs.mathworks.com/community/2011/03/28/using-uiwaituiresume-to-control-program-flow/
• https://www.mathworks.com/help/matlab/ref/uiwait.html#:~:text=uiwait%20blocks%20execution%20until%20the,the%20figure%20f%20is%20deleted.
• https://www.mathworks.com/help/matlab/ref/uiresume.html

There are various examples on how to use it in these links.

[Vasista Adupa]

Thanks for the links, I saw it earlier, But It didn't provide exact syntaxes similar to one in app designer. I tried this,

I did create a small GUI which has a continue button, when pressed exits the GUI. From my understanding uiwait should start as soon as the figure starts, so that my code in the background can stop executing. Here's a simple code I ran.

%% Script written to test it%%%%%%%%%
a = 150;
b = 200;
APPINFO = matlab.apputil.install('./APP/app');
matlab.apputil.run('appAPP')
c = a+ b + rolls;

%%%%%%% This is a part of the code from app designer Code View %%%%%%%%
 methods (Access = private)
        % Code that executes after component creation
        function startupFcn(app)
            uiwait(app.UIFigure)
        end

        % Button pushed function: ContinueButton
        function ContinueButtonPushed(app, event)
            if app.ContinueButton.Enable
                roll = 1500;
                assignin("base","rolls",roll);
                closereq
            end
            
        end
    end

In the Background it is saying as Pause (which is what I needed), But when I click on the continue button an error pops up.

Error using getappdata
Value must be a handle.

Error in appApp/attachOncleanupToFigure (line 109)
            appdata = getappdata(fig);

Error in appApp/startApp (line 94)
                obj.attachOncleanupToFigure(appdesigner.internal.service.AppManagementService.getFigure(obj.AppHandle));

Error in appApp (line 48)
            startApp(obj)

Error in appinstall.internal.runapp>execute (line 116)
out = evalin('caller', [script ';']);

Error in appinstall.internal.runapp>runapp13a (line 95)
outobj = execute(fullfile(appinstalldir, [wrapperfile 'App.m']));

Error in appinstall.internal.runapp>preamble18b (line 60)
    appobj = runapp13a(appinstalldir);

Error in appinstall.internal.runapp (line 13)
    out = preamble18b(appinstalldir);

Error in matlab.apputil.run (line 45)
appinstall.internal.runapp(appName, appLocation);

Error in trail_uwait_uresume (line 7)
matlab.apputil.run('appAPP')

It might be trivial, But I am not getting it honestly.

Thank you.

[Vasista Adupa]

For now, I am using this as a work around.

a = 150;
b = 200;
rolls =zeros(1)
APPINFO = matlab.apputil.install('./APP/app');
matlab.apputil.run('appAPP')

while isequal(rolls,zeros(1)) == 1
    pause
end

c = a+ b + rolls;