Smooth transition (optical effect) between uitabpanels

Hi. I have designed a group of three uitabpanels objects.

htab = uitabgroup('v0');
th1 = uitab('v0',htab,'title','Panel 1','ButtonDownFcn',...
    @th1_ButtonDownFcn);
th2 = uitab('v0',htab,'title','Panel 2','ButtonDownFcn',...
    @th2_ButtonDownFcn);
th3 = uitab('v0',htab,'title','Panel 3','ButtonDownFcn',...
    @th3_ButtonDownFcn);

My intention is having a smooth optical transition between them when I change the selected uipanel through the mouse click. I pretend to achieve it changing the 'Visible' property of the elements contained inside them using the ButtonDownFcn function ( I got this idea based on the description section of http://www.mathworks.com/matlabcentral/fileexchange/4780-tab-panel-yet-another-one).

    set(handles.th2,'Visible','off');
    set(handles.th3,'Visible','off');
...
  function th1_ButtonDownFcn(hObject, eventdata)
  handles = guidata(fh);
  set(handles.th1,'Visible','on');
  set(handles.th2,'Visible','off');
  set(handles.th3,'Visible','off'); 
  guidata(fh,handles);
  end

function th2_ButtonDownFcn(hObject, eventdata)
handles = guidata(fh);
set(handles.th1,'Visible','off');
set(handles.th2,'Visible','on'); 
set(handles.th3,'Visible','off');
guidata(fh,handles);
end

function th3_ButtonDownFcn(hObject, eventdata)
handles = guidata(fh);
set(handles.th1,'Visible','off');
set(handles.th2,'Visible','off');
set(handles.th3,'Visible','on');
guidata(fh,handles);      
end

where

fh: handle of the figure where they are contained the uitabpanels.

handles.th1, handles.th2, handles.th3: handles of the elements contained into each uitabpanel respectively.

However, it has not worked (I click on each one of uitabpanel's tabs and the visibility of them do not change) and I do not understand why.

Answer 1

[Julián Francisco]

In conclusion, the ButtonDownFcn and SelectionChangeFcn functions of an UITAB are already active when you click in the tab´s label. So it is not possible to achieve the desired target (smooth optical transition) because the obtained result (modifying the mentioned functions) is the same that doing nothing.

Answer 2

[Jan]

The ButtonDownFcn of a UITAB is triggered, if you click in the tab's contents area. I assume you want to use the SelectionChangeFcn function of the UITABGROUP to detected a changed active tab.

[Julián Francisco]

@Jan Simon: Thank you for your help. However, your solution does not work either. The SelectionChangeFcn is already triggered when the uitabgroup is created. I have obtained the same transition with and without defining the SelectionChangeFcn Callback. I think my problem is due to the design. In the panel 3 I have an axes with 'BackgroundColor' = black, and the others have elements with colors gray and white. So,when I have to activate the panel 3, the transition is not smooth.

[Jan]

@Julian: I admit, I do not get the point of "smooth transition". Do you mean an optical effect?

[Julián Francisco]

@Jan Simon: Yes, Jan. I refer to that. It is my fault. I should have written "smooth optical transition..." in the title of the question. Sorry. Thank you for your correction. Cheers.