Matlab GUI doesn't update the switch value while running

I am trying to create a simple GUI which will play and stop sound based on a switch. However, it seems that the button value is not getting updated at all.

Load Sound will simply load the sound file. I want the sound file to play repeatedly until I stop. I tried using a state button, a toggle button, a switch but nothing seems to work. Here is my code:-

        % Loading the sound works fine
        function Load_Sound(app)
            app.Button.Text = 'Wait!!' ;
            [y,app.Fs] = audioread('Media1.m4a');
            app.y_sec = y((8.1*1e+6 + 0.032*app.Fs):(8.1*1e+6 + 0.239*app.Fs));
            app.Button.Text = 'Loaded' ;
        end
        
        % Switch value changed function
        function SwitchChangedValue(app)
            num = 0;
            while(1)
                sound(app.y_sec,app.Fs);
                disp(['Sound is on ' num2str(num)])
                disp(app.Switch.Value)
                pause(2)
                num = num +1;
                if(app.Switch.Value==0)
                    disp(app.Switch.Value)
                    pause(2)
                    break
                end
            end
        end
        end
        
        %% OR THE FOLLOWING
        
        % StateButton value changed function
        function Start_State(app)
            value = app.StateButton.Value;
            if(value==1)
                app.StateButton.Text = 'Stop' ;
            else
                app.StateButton.Text = 'Start' ;
            end
            num = 0;
            while(1)
                sound(app.y_sec,app.Fs);
                disp(['Sound is on ' num2str(num)])
                disp(app.Switch.Value)
                pause(2)
                num = num +1;
                if(app.StateButton.Value==0)
                    disp(app.StateButton.Value)
                    pause(2)
                    break
                end
            end
            disp(value);
        end

My while loop doesn't seem to exit even if the state of the state button or switch is changed. It keeps on running and I have to force shut the program each time. I don't understand why the new value of switch/state is not reflected in the function, when I change the state. Any help will be great. I have been trying to fix this since long time now.

Answer 1

[Image Analyst]

Put in a drawnow whenever you want ot force the screen to repaint

drawnow;

[Manish Kumar Nayak]

I am sorry, I didn't understand. How will this be beneficial exactly?

[Image Analyst]

I thought you meant the image of the switch on the GUI is not changing when it should.

[Manish Kumar Nayak]

No no, that's working fine. My while loop doesn't exit is my main problem.

[Image Analyst]

You don't have a failsafe. Never use a while loop without a failsafe just in case your main exit condition never happens.

maxIterations = 1e10; % Whatever.
loopCounter = 0;
while loopCounter < maxIterations  % Instead of while(1)
    % code....
    loopCounter = loopCounter + 1;
end

That said, I'm not sure (without running it) why your "break" line never gets hit and so your code never exits the while loop. Try stepping through the code.