Why does the callback for the edit box in my GUI execute twice in MATLAB 7.0.1 (R14SP1)?

When I change the value of the 'String' property in the edit box callback function, the callback is executed a second time when the edit box loses focus.

Answer 1

[MathWorks Support Team]

This is expected behavior. The callback event for an edit box is triggered by changing the String property and then changing the object focus.

To work around this issue, set a flag in the callback procedure that prevents the entire callback from being executed once the edit box loses focus.

For example:

function myedit_callback(hObject, eventdata, handles)

persistent myEditboxFlag

if isempty(myEdtiboxFlag)

    myEditboxFlag = true;

end

if myEditboxFlag

    %perform callback procedure

    set(hObject, 'String', 'A new string')

    myEditboxFlag = false;

else

    myEditboxFlag = false;

end