Trouble loading GUI variables into handles

Guys -

This one's driving me nuts. I want to save the state of my GUI with many pushbuttons and text windows so that when I load the saved .mat file later the values will be put back into the handles structure and the GUI will look like it did when I saved it. I can save the GUI state vector just fine this way:

state.KMCsource = get(handles.KMCsource);
state.sourceKmeansVRC = get(handles.sourceKmeansVRC);
state.sourceFCM = get(handles.sourceFCM);
state.FCMXBVRC = get(handles.FCMXBVRC);
state.KMsourceclust = get(handles.KMsourceclust);.
.
.

and so on, and I end up with a structure variable called 'state' that contains the complete handles data for all the elements of my GUI. The problem comes when I reopen the GUI and want to pass all this data into the GUI handles and have the GUI reflect the configuration of the state in which it was last saved. When I attempt:

set(handles.KMCSource,state.KMCsource);

I get the "invalid handle object' error because at this point the GUI handles are just floating point numbers that don't seem to point to the GUI elements. So my question is this: Once I have saved all the relevant handle data in a structure called 'state', how do I get that data back into handles such that the GUI looks the way it did when I closed it?

Answer 1

[Jan]

Handles are in fact floating point numbers. As long as the corresponding element is not deleted, a handle is a unqiue address of an object.

How do you obtain the handles struct after re-creating the figure? Do you try to use the former handles?

Answer 2

[Walter Roberson]

If you are restoring at a point where the old graphics are gone (e.g., after re-starting the program), then you will have to create uicontrol and text objects corresponding to each control that will be re-set; then you can set() their state.

You will probably run in to notable problems because not all properties that can be get() can be set().

You also have to watch out for hidden properties, and you will have to watch out because some fields of some graphics objects will contain graphics object references to objects you did not explicitly create (e.g., titles on axes objects)

There is another problem you will face that will lead to problems: you will be wanting to re-create the hierarchy. When you are "live" the hierarchy is expressed through the 'Parent' and 'Children' properties. You can save those properties but restoring them is going to lead to problems as they are graphics handles that will refer to the old numbering.

All in all, you might find it a lot easier to saveas() your figure and let the MATLAB serialization routines take care of all the details.

[Jason]

Jan and Walter -

I've noticed that if I close and then reopen the GUI during the same MATLAB session, the get and set commands result in the restoration of the GUI with my existing code. I was trying to put together code that will allow a GUI restore with my saved handles structure after closing MATLAB completely - that's when everything goes to hell.

Walter, you say that the saveas() command may work to do this? What format should I select that will resurrect the GUI from a previous session?

[Walter Roberson]

saveas() a .fig file.

[Jason]

How can I call saveas() from within the GUI to save the figure as a specific session name? I seem to be having trouble making saveas() save the GUI figure. I tried pointing saveas() to hObject, but that's the handle of the button in the GUI that I'd like to have execute saveas, not the GUI figure itself.