ScrollBar.qml Example File

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  import QtQuick 2.2

  Item {
      id: container

      property variant scrollArea
      property int orientation: Qt.Vertical

      opacity: 0

      function position()
      {
          var ny = 0;
          if (container.orientation == Qt.Vertical)
              ny = scrollArea.visibleArea.yPosition * container.height;
          else
              ny = scrollArea.visibleArea.xPosition * container.width;

          if (ny > 2)
              return ny;
          else
              return 2;
      }

      function size()
      {
          var nh, ny;

          if (container.orientation == Qt.Vertical)
              nh = scrollArea.visibleArea.heightRatio * container.height;
          else
              nh = scrollArea.visibleArea.widthRatio * container.width;

          if (container.orientation == Qt.Vertical)
              ny = scrollArea.visibleArea.yPosition * container.height;
          else
              ny = scrollArea.visibleArea.xPosition * container.width;

          if (ny > 3) {
              var t;
              if (container.orientation == Qt.Vertical)
                  t = Math.ceil(container.height - 3 - ny);
              else
                  t = Math.ceil(container.width - 3 - ny);
              if (nh > t)
                  return t;
              else
                  return nh;
          } else
              return nh + ny;
      }

      Rectangle { anchors.fill: parent; color: "Black"; opacity: 0.3 }

      BorderImage {
          source: "images/scrollbar.png"
          border { left: 1; right: 1; top: 1; bottom: 1 }
          x: container.orientation == Qt.Vertical ? 2 : position()
          y: container.orientation == Qt.Vertical ? position() : 2
          width: container.orientation == Qt.Vertical ? container.width - 4 : size()
          height: container.orientation == Qt.Vertical ? size() : container.height - 4
      }

      states: State {
          name: "visible"
          when: container.orientation == Qt.Vertical ?
                    scrollArea.movingVertically :
                    scrollArea.movingHorizontally
          PropertyChanges { target: container; opacity: 1.0 }
      }

      transitions: Transition {
          from: "visible"; to: ""
          NumberAnimation { properties: "opacity"; duration: 600 }
      }
  }