title: How do I know if my Widget is obscured by another application or visible to the user?
body: <p>Create a new widget, show it, and hide it behind another application.</p>
  
  <blockquote>
    <p>Is there a way to find out if the widget is visible to the user?
    For example, if you have two applications running and visible to the user (obviously only one of them has focus and is active) but both are visible</p>
  </blockquote>
  
  <p>The reason I am interested in this is because my widget has a treewidget which calls setText() (which is very expensive) so I want to optimize the performance by updating only when the treewidget is visible to the user. </p>
  
  <blockquote>
    <p>But in general, I'd like to know if there's a way of find "if the widget is visible to the user or not." </p>
  </blockquote>
  
  <p>Thank you for any suggestions and alternatives.</p>