title: WPF Window GotFocus / LostFocus
body: <p>I have a simple task to accomplish, or at least in appearance ...</p>
  
  <p>I'd like to handle the fact that a window is currently the current selected window in the Windows environment or not.</p>
  
  <p>I thought I had just to handle the two event LostFocus and GotFocus of my window, but they don't fired. I can select the window or click elsewhere on the desktop, none of the events are triggered..</p>
  
  <p>The GotFocus event only fired when I reduce or maximize the window.</p>
  
  <p>Am I doing something wrong ?</p>
  
  <p>Thank you.</p>