Break loop with button click Appdesigner GUI [Both plot and button are in different callback functions]

I have a GUI MATLAB

I have a button

and there is a loop like this

function RUN()
t=1:0.01:3600;
for i=1:numel(t)
    y(1,i)=readValue();
    plot(t(1:i),Tco(1:i));
    pause(0.02)
end
end

function BUTTON_PRESS()
   %BREAK FROM THAT LOOP
end

I want to break this loop when I click my button

Answer 1

[Jan]

function main
FigH    = figure;
ButtonH = uicontrol(FigH, 'Style', 'PushButton', 'String', 'Stop', 
                    'Callback', @ButtonPressed, 'UserData', 0);
RUN(ButtonH);
end

function ButtnPressed(ButtonH, EventData)
ButtonH.UserData = 1;
end

function RUN(ButtonH)
t = 1:0.01:3600;
for i = 1:numel(t)
    y(1,i) = readValue();
    plot(t(1:i), Tco(1:i));
    pause(0.02);
    if ButtonH.UserData
        break;
    end
end
end

If there is really no chance to obtain a clean providing of the button's handle, use the tag to find it dynamically - but this is less nice:

function main
FigH    = figure;
ButtonH = uicontrol(FigH, 'Style', 'PushButton', 'String', 'Stop', ...
    'Callback', @ButtonPressed, 'UserData', 0, ...
    'Tag', 'myUniqueButtonTag_in: main.m');
RUN();
end

function ButtnPressed(ButtonH, EventData)
ButtonH.UserData = 1;
end

function RUN()
ButtonH = findobj(allchild(groot), 'Tag', 'myUniqueButtonTag_in: main.m');
... same as above
end

Care for the situation, where two figures are existing or none, e.g. by:

function RUN()
ButtonH = findobj(allchild(groot), 'Tag', 'myUniqueButtonTag_in: main.m');
if numel(ButtonH) > 1
    warning('Multiple stop buttons found.')
end

...
    if ~isempty(ButtonH) && any([ButtonH.UserData])

end

[shubham kumar gupta]

can you help me I tried this

2nd pic: In appdesigner Inside a callback to a button "PLOT AND SIM" i passed a function main_plot_function()

1st pic: shows that main_plot_function Now "STOP BUTTON " appears but clicking on that it doesnt stops loop of plotting nor it print "BUTTON!!"

IT WORKS IN DEBUG MODE BUT NOT IN NORMAL MODE

[shubham kumar gupta]

Works only in Debug mode and not normal mode.. why is it so?

[shubham kumar gupta]

cool solved I increased the pause time!! :) but Thats what actually happens when I click Breakpoints stop

Somehow It working!

[Jan]

Hint: Avoid global variables, because they are a shot in your knee.

Answer 2

[Voss]

You can define a variable that says whether the button has been clicked. Set the value of that variable in your button's callback function. Check the value of that variable on each iteration of your for loop, and if it says the button has been clicked, break out of the loop.

[shubham kumar gupta]

problem is there are two functions one is RUN and another is BUTTON PRESS

RUN CONTAINS PLOT CODE

AND I WANT TO BREAK FROM IT VIA BUTTON PRESS

[Voss]

Your variable that says whether the button has been clicked (let's call it "is_button_clicked" for the sake of discussion) will need to be available to both functions. There are a number of ways to achieve this:

1) you can store is_button_clicked in the handles structure of your GUI (if you are using GUIDE, this structure is accessible via guidata())

2) you can make RUN() and BUTTON_PRESS() nested under another function that contains is_button_clicked

3) you can make is_button_clicked a global variable

[shubham kumar gupta]

My final aim is to get a standalone app with pause and start feature of plot so I need to break this loop on button click

I tried this but not worked

  function RUN_PLOT()
    time=1:0.01:3600;
    figure
    hold on;
    global flag;
    i=1;
    flag=true;
    while(flag && i<numel(t))
      y(1,i)=readValue(
      plot(t(1:i),y(1:i));
      pause(0.02)
      i=i+1;
    end
  end 
on Button click I did this

 function BUTTON_PRESS()       
    global flag
    flag=false
 end

[Rik]

Do not use a global. It is much better to share data through guidata or by making them nested functions. You can even set the flag value as the UserData of a GUI element.

All other functions can access and overwrite global variable contents. Especially with such a short name as flag this risk is non-zero. If you really insist on using global variable, make the name as long as you can: include the function name and include a long description. You have 63 characters, use them.

global RUN_PLOT_GUI___flag_to_stop_plotting_loop_if_true

[shubham kumar gupta]

NO HELPED!! Tried unable to stop loop even changing the name flag to RUN_PLOT_GUI___flag_to_stop_plotting_loop_if_true!!

[Rik]

Changing the name will not solve anything if your code is not working in the first place. It is a good habit.

Instead of holding down the shift button while typing on this forum (which is considered SHOUTING and impolite), did you try using breakpoints to debug your code?