MATLAB: Wait for user to draw rectangle

drawrectangleimcrop

would like to crop an image using drawrectangle, the thing is I want the user to be the one who ends the selection process that's why I thought about using waitfor but it didn't work so far, can you explain why? here is my code

if true
  function select_roi_Callback(hObject, eventdata, handles)
% hObject    handle to select_roi (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
guidata(hObject, handles);
A = handles.I;
h = drawrectangle(handles.axes1);
waitfor(h);
I = imcrop(A,h.Position);
imshow(I);  
handles.I = I;
guidata(handles.figure1,handles);
h = datacursormode;
set(h,'DisplayStyle','datatip',...
  'SnapToDataVertex','off','Enable','on')
end
thank you!

Best Answer

If you use imrect instead, the code will pause until the user finalizes the rectangle selection by double-clicking.

h=imrect;
wait(h);

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