title: displaying the opencv window on top Qt(c++) dialogs/widgets
body: <p><a href="https://i.stack.imgur.com/Rl0d7.jpg" rel="nofollow noreferrer">image1</a>
  <a href="https://i.stack.imgur.com/ksbgI.png" rel="nofollow noreferrer">image2</a></p>
  
  <p>I am new to Qt. I am developing a Qt(c++) and opencv application on Ubuntu 14.</p>
  
  <p>My application has three Qt diaglog windows.The 2nd dialog opens by pressing the pushbutton on the first dialog. The 3rd dialog opens by pressing the pushbutton on the 2nd dialog. </p>
  
  <p>In the 3rd dialog on the press of a push button i do some image processing operations using opencv and display the results using opencv function namedWindow.  This is shown in image1</p>
  
  <p>The problem is the opencv windows("source" and "centers") are not displayed on top of the 3 qt dialogs. This is shown in image2 </p>
  
  <p>How do i display the opencv windows on top of all the qt dialogs and have complete access to the opencv window to perform operations like clicking on pixels, rectangular selection , thresholding using scroll bar(basically mouse call back) on the opencv window.</p>
  
  <p>Please help me out with this problem</p>
  
  <p>Thanks</p>