MATLAB: What’s the difference between handles and hObject

handles hobject function eventdata matlab values gui

Where do I use handles and hObject?? And why are there function which contain sometimes both of them plus eventdata and other one of those 3 is missed?? for example function pushbutton1_Callback(hObject, eventdata, handles)

Best Answer

hObject is the handle to the calling object; i.e. the object that is calling the function. handles is a structure with all of the handles to all objects.

The only time I use hObject is if I have two objects sharing a callback, e.g. pushbutton1 and pushbutton2 both call foo_Callback. In this scenario, I would use hObject to determine which one called or if we needed to modify the calling object.

Related Solutions

MATLAB: H i every one , i need to declare a counter such that if any one of the four buttons is pressed a specefic funtion specified in the fifth button is performed.Suppose UserData can not be used it reserved for something else

Use guidata, which calls setappdata and getappdata internally:

function pushbutton1_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
handles.counter = 1;
guidata(hObject, handles);
% And the same for the other callbacks...
function pushbutton5_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
switch handles.counter
  case 1
  case 2
  case 3
  case 4
  otherwise  % No SWITCH without OTHERWISE
    error('Programming error')
  end
end

MATLAB: OpeningFcn not saving handles

This is occurring because in your OpeningFcn, you are calling "guidata" after calling your callback function.

guidata can manage only one variable at any time. Subsequent calls to guidata(object_handle,data) overwrite the previously stored data.

For this reason, your call to "guidata" after your callback function is overwriting the new handles values. Instead, call "guidata" and then call your callback function.

function test_OpeningFcn(hObject, eventdata, handles, varargin)
handles.output = hObject;
guidata(hObject, handles);
pushbutton1_Callback(hObject, eventdata, handles) %call after guidata so not overwritten

Best Answer

Related Solutions

MATLAB: H i every one , i need to declare a counter such that if any one of the four buttons is pressed a specefic funtion specified in the fifth button is performed.Suppose UserData can not be used it reserved for something else

MATLAB: OpeningFcn not saving handles

Related Question