Thread Subject: Matlab Gui - Handles Error

Hello, I'm new to matlab and I'm coding a GUI.

My aim is create a total of two interfaces, setting them all invisible. If button 1 is clicked, half of them are made visible. If button 2, the other half. I set up a function which created all objects and made them all invisible. I set up a button with a callback. I then set up the callback function to set many UIObjects visible. When the button is clicked, I got the error message:

??? Reference to non-existent field 'Text 1'.

It seems as though the objects are not able to be 'recognised' outside their initial function. I tried adding the line:

guidata(hObject,handles)

Which I understand 'updates' the handles structure. I then got the error message:

??? Input argument "hObject" is undefined.

Can anyone give me a clue as to what I'm doing wrong?

Here is an example of how I've coded it ...
  function build_all_objects(hObject, eventdata, handles, varargin)
handles.fig = figure('units','pixels',...
                        'position',[220 150 750 550],...
                       'resize','off',...
                       'name','Untitled',...
                       'numbertitle','off',...
                       'color', [0.925,0.914,0.847],...
                       'menubar','none');

%Creates the pushbutton
handles.Button1=uicontrol('style','pushbutton',...
                        'position',[10 530 200 20],...
                             'string','Button1',...
                           'enable','on',...
                           'callback',{@Callback, handles});

function Callback(hObject, eventdata, handles)
set([handles.Button1],'visible','no')

Any help would be much appreciated.

Hi Brian

I think there may be two problems here. Firstly, try returning the handles structure from your function eg:

function handles = make_all_panels(hObject, eventdata, handles)

       handles.fig1 = uipanel(...some code)

       handles.button = uicontrol('style', 'pushbutton', etc)

       guidata(hObject, handles)

end

Then call your function from your main program like this

handles = make_all_panels(hObject,eventdata,handles)

This my help with ensuring that your new objects are added to the handles structure.

Secondly, your callbacks may be the problem. I found that if you use guide to make an example button then copy and paste the callback it makes, it looks something like this:

'callback', @(hObject,eventdata)myGui('button1_callback',hObject,eventdata,guidata(hObject))

if you use this format, your gui will recognise the hObject and handles structure. Try these.. I was stuck with a similar problem for quite a while.

Hope this helps

Chris