title: How to make a particular area of qml view transparent
body: <p>There is a qml file like this:</p>
  
  <pre><code>Item {
      width: 800
      height: 600
  
      Image {
          id: background
          width: 800
          height: 600
          source: "qrc:/resorces/background.png"
      }
  
      Rectangle {
          id: transframe
          x: 500
          y: 200
          width: 200
          height: 100
      }
  
  }
  </code></pre>
  
  <p>How to make the area of transframe transparent, then I can see the graphic under background.</p>