You can have a callback called regularly during the duration of a program by using the 'timer' object. Create a timer in the OpeningFcn of your GUIDE application, and assign it the callback you wish to call repeatedly. Here is an example:
function TestGUI_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% varargin command line arguments to untitled (see VARARGIN)
% Choose default command line output for untitled
handles.output = hObject;
t = timer();
t.Period = 2;
t.ExecutionMode = 'fixedRate';
t.TimerFcn = @TimerFcn; % Here is where you assign the callback function
handles.timer = t; % Put the timer object inside handles so that you can stop it later
start
(t)
% Update handles structure
guidata(hObject, handles);
Then, when you want to stop the timer, you can do so in any callback in your application with this line:
stop(handles.timer)
For an alternative approach, see this MATLAB Answers post:
