title: Setting focus on a window in opencv
body: <p>I am trying to open a window in opencv (with imshow) and focussing the window so that the user can directly give an input to the window. The first time I open a window this works, but after calling destroyAllWindows and then reopening a new window, the focus is not set to this window<br>
  How can I force opencv to focus on this special window?</p>
  
  <p>Thanks</p>