Warning Message when someone is closing GUI in Matlab

Question

How can I make warning message in GUI Matlab, when the user is closing the gui (using rght top 'x').

Answer 1

You can set the figure's CloseRequestFcn to, for example, ask the user if they really want to close the figure or not. You can use a built-in modal window, like questdlg, for this purpose. An example of such a function is given in the above documentation:

function my_closereq(src,evnt)
% User-defined close request function
% to display a question dialog box
   selection = questdlg('Close This Figure?',...
                        'Close Request Function',...
                        'Yes','No','Yes');
   switch selection,
      case 'Yes',
         delete(gcf)
      case 'No'
         return 
   end
end