title: Qt show modal dialog (.ui) on menu item click
body: <p>I want to make a simple 'About' modal dialog, called from Help->About application menu. I've created a modal dialog window with QT Creator (.ui file). </p>
  
  <p>What code should be in menu 'About' slot?</p>
  
  <p>Now I have this code, but it shows up a new modal dialog (not based on my about.ui):</p>
  
  <pre><code>void MainWindow::on_actionAbout_triggered()
  {
      about = new QDialog(0,0);
      about-&gt;show();
  }
  </code></pre>
  
  <p>Thanks!</p>