GUI Handles Visibility Different

Please see the attached image. I'm using the handles structure to pass values between a GUI and a main m file, but the variables I've created disappear when I try to access them in the main file, while I am able to access the other handles with the different icon. I'm not sure why I'm unable to access the last two variables.

Answer 1

[Walter Roberson]

After you change the contents of the handles structure, be sure to use

guidata(hObject, handles)

where hObject is the name of the first parameter to your function (GUIDE tends to name it hObject)

[CGN]

I have done this, but the handles structure still does not seem to be updating to include the new values.

[Walter Roberson]

If you are running a routine, and a different routine updates handles, then that does not update the handles in the first routine.

For example, you might have a pushbutton that starts a plotting loop

function do_plotting(hObject, event, handles)
while handles.keep_going
  do some plotting
  drawnow()
end

and you might have a pushbutton

   function stop_plotting(hObject, event, handles)
   handles.keep_going = false;
   guidata(hObject, handles);

that is intended to tell the loop to stop.

But "handles" is not a global structure. What gets passed in to a routine is a copy of the handles structure as of the time the routine starts. The guidata() in stop_plotting updates the master copy of the handles structure but does not affect the copy that is local to the do_plotting function.

If you are running a routine and you have reason to expect that some other routine might have updated handles and you need to see the updated version, then you need to use guidata() to retrieve the updated copy:

function do_plotting(hObject, event, handles)
while true
  handles = guidata(hObject);   %pull in current version
  if ~handles.keep_going; break; end
  do some plotting
  drawnow()
end