title: How to detect that a control is being moved?
body: <p>Suppose I have a window with a custom UserControl, and the UserControl has a textbox inside.  When I drag the window around, how can the TextBox detect that it is being moved ?</p>
  
  <p>I tried to search around its RenderTransform property, there is that Change event that gets fired when "the Freezable object or one of its objects change". Nothing conclusive..</p>
  
  <p>Edit :</p>
  
  <p>In my case, I don't see the window, all I see is the UserControl and I can't go any higher.</p>