MATLAB: Help with set function, ‘CloseRequestFunc’ and Calling variables out of the function.

Question

I'm trying to use matlab to directly alter the contrast of an stock image with just the imcontrast figure. and link my contrast adjustments to the imadjust function. This way, I can automatically adjust contrast in an image without having to write any numbers down or save an image. I use the Closerequestfunc to trigger a function that records the final contrast values on the slider when I close out of the contrast figure. My trouble is that I cannot figure out a way to use the the final variables (the windowclose_min ; windowclose_max) in my function outside of the function unless I make them global variables. Pls Help!

Note!!! Do not hit "Adjust Data" in the imcontrast figure, just adjust the bars and close.

    I = imread('pout.tif')
    imshow(I)  
    imcontrast; 
    F = imcontrast(gcf);
    window_min = str2double(get(findobj(F, 'tag', 'window min edit'), 'String'));
    window_max = str2double(get(findobj(F, 'tag', 'window max edit'), 'String')); 
    disp(window_min) %toggle on and off at will

    disp(window_max) %toggle on and off at will
    set(F, 'CloseRequestFcn', @(s,e)getValues(s)); %This function still confuses me. I do not know what the s or e represent.
    uiwait %activates once you close out of the first image (I)
    G = imadjust(I,[closewindow_min/window_max closewindow_max/window_max],[0 1]);
    imshowpair(I,G,'Montage')
function getValues(F)
     global closewindow_min
     global closewindow_max
     closewindow_min = str2double(get(findobj(F, 'tag', 'window min edit'), 'String'));
     closewindow_max = str2double(get(findobj(F, 'tag', 'window max edit'), 'String'));
     disp(closewindow_min);
     disp(closewindow_max);
     delete(F) %This is the only way I could figure out how to close the imcontrast figure
  end

Answer 1

One easy solution is to use a nested function (will not work for GUIDE: use guidata instead). Basically you would need to do something like this (pseudocode):

function out = mainfun(imh)
out = []; % important to allocate here!
ich = imcontrast(imh);
set(ich, 'CloseRequestFcn',@myClose)
%

    function myClose(h,e)
        out = get(findobj(h,'tag','window min edit'), 'String');
        delete(h)
    end
end
%
waitfor(ich)
end

and call it like this:

imh = imshow(I);
new = mainfun(imh)