User`s guide

Customizing Callbacks in GUIDE

In this section...

“GUIDE Callback Templates” on page 8-15

“Callback Names and Signatures in GUIDE” on page 8-16

“GUIDE Callback Arguments” on page 8-20

“Changing Callbacks Assigned by GUIDE” on page 8-22

GUIDE Callback Templates

GUIDE defines conventions for callback syntax and arguments and

implements these conventions in the callback templates it adds to the GUI

code. Each template is like this one for the

Callback subfunction for a push

button.

% --- Executes on button press in pushbutton1.

function pushbutto n1_Callback(hObject, eventdata, handles)

% hObject handle to pushbutton1 (see GCB O)

% eventdata reserved - to be defined in a future v ersion of MATLAB

% handles structure with handles and user data (see GUIDATA)

...

The first comment line describes the event that triggers execution of the

callback. This is followed by the function definition line. The remaining

comments d escribe the input arguments. Insert your code after the last

comment.

Certain figure and GUI component callbacks provide event-specific data in

the

eventdata argument. As an example, this is the template for a push

button

KeyPressFcn callback.

% --- Executes on key pr ess with focus on pushbutton1

function pushbutto n1_KeyPressFcn(hObject, eventdata, handles)

% hObject handle to pushbutton1 (see GCB O)

% eventdata structure with the following fields (see UICONTROL)

% Key: n ame of the key that was pressed, in lower case

% Character: character interpretat ion of the key(s) that was pressed

8-15