User`s guide

Initialize a GUIDE GUI

In this section...

“Opening Function” on page 8-25

“Output F unction” on page 8-28

Opening Function

The opening function is the first callback in every GUI code file. It is executed

justbeforetheGUIismadevisibletotheuser,butafterallthecomponents

have been created, i.e., after the components’

CreateFcn callbacks, if any,

have been run.

You can use the opening function to perform your initialization tasks before

the user has access to the G UI. For example, you can use it to create data or

to read data from an external source. GUI command-line arguments are

passed to the opening function.

• “Function Naming and Template” on page 8-25

• “Input Arguments” on pag e 8-26

• “Initial Template Code” on page 8-28

Function Naming and Template

GUIDE names the opening function by appending _OpeningFcn to the name

of the GUI. This is an exam ple of an opening function template as it might

appear in the

mygui code file.

% --- Executes just before mygui is made visible.

function mygui_Ope ningFcn(hObject, eventdata, handles, varargin)

% This function has no output args, see OutputFcn.

% hObject handle to figure

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

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

% varargin command line arguments to mygui (see VARARGIN)

% Choose default command line output for mygui

handles.output = hObject;

8-25