Access variable of my GUI from an output figure?

My GUI can output a figure which shows all the result. I use uicontrol to add a few buttons in the figure. But i don't know how to access my GUI variable from these buttons. Pls help. I have tried setappdata and getappdata. But still not working. Any one give a guide. Very grateful for your help.

function BtnBuffer_Callback(hObject, eventdata, handles)

   handles.output =hObject;

   BatchAnalysis(hObject, eventdata, handles);

   guidata(hObject,handles);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function BatchAnalysis(hObject, eventdata, handles)
  ...
  ...
figureHandle = figure;   %output a figure 
h = handles.BtnCrop;
x = getappdata(h,'cropX');
y = getappdata(h,'cropY');
u1 = uicontrol('Style','push',...
'parent', figureHandle,...
'pos',[1470 500 80 80],...
'string','Back',...
'Enable','off',...
'Callback',@buttonBack); 
...
...
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function buttonBack(hObject, eventdata, handles)
handles.output = hObject; 
set(u2, 'Enable','on');
if(ind > 1)
    set(u1,'Enable','on');
    ind = ind-1;
    hold on
    h = handles.BtnCrop;% the crop button in GUI, i want to capture my crop mark
    x = getappdata(h,'cropX');
    y = getappdata(h,'cropY');
    batchPlot(final,blockImage,row,col,mag,pha,ind,x,y);
    if(ind == 1)
        set(u1,'Enable','off');
    end
else
    set(u1,'Enable','off');
end
guidata(hObject,handles);

e.g. in function buttonBack, i want to access handles.BtnCrop in my GUI, error says no such reference. What can i do? I have been suffering this problem for quite a few days and still can't figure out.

[Ben11]

where do you use setappdata?