Adrien - you will want to use the guidata function to set and retrieve user-defined data to the GUI. If you were developing your GUI with GUIDE, this would typically be a structure called handles which is usually an input parameter to all callbacks. Here, you are doing almost the same thing but with a structure called S. (You may want to change your S to handles just to make it clear what this structure contains.)
You have assigned your callbacks as
set(S.pB_save, 'Callback', {@pB_save_callback, S});
set(S.eT_name, 'Callback', {@eT_name_callback, S});
which is fine, but you have to realize that the S that gets passed as the third input parameter to these callbacks is a copy of the S at the time that these callbacks were assigned. So if one callback updates some data in this structure, another callback won't see these changes in S because it receives an out-of-date copy of S. So you can remove the S from each of the above to just have
set(S.pB_save, 'Callback', {@pB_save_callback});
set(S.eT_name, 'Callback', {@eT_name_callback});
We will use guidata to get the most up-to-date handle and user-defined data.
Note that you should add the following line once all handles have been set to S
guidata(S.f,S);
This will save all handles to the GUI so that you can access them at will whenever you call guidata(hObject) from within any of your callbacks.
Your eT_name callback then becomes
function [] = eT_name_callback(hObject, event data)
% get the handles and user-defined data
handles = guidata(hObject);
% set the name field within the (local) handles structure
handles.s_Name = get(hObject, 'String');
% save the data to the (global) handles structure
guidata(hObject, handles);
Note that I have just replaced S with handles and am using hObject to retrieve and set the handles structure.
Your pB_save callback then becomes
function [] = pB_save_callback(hObject, eventdata)
% get the handles and user-defined data
handles = guidata(hObject);
if isfield(handles,'s_Name')
% display the name
display(handles.s_Name);
end
Note how we check to make sure that s_Name is a field within the handles structure before we try to access it.
Of course, the alternative to the accessing handles for s_Name is to just access the widget directly using its handle
display(get(handles.eT_name,'String'));
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The above describes two ways on how you can access the string data from your callback.
S is the structure of GUI widget handles and user-defined data, where the latter is set using the guidata function.
To save an array to the GUI, just do the same thing as you did with the string
handles.arrayData = [1 2 3 4 5];
guidata(hObject,handles);
The above saves an array with five elements, that you can then access in any other callback.
Try the above and see what happens!
