qt qml scrollbar 移動APP風格的滾動軸

依附於Flickable組件的滾動軸
    自動放置在恰當位置
    拖動時顯示，不動時消失
Lisence: MIT 請保留此聲明
Author: surfsky.cnblogs.com 2014-12

【先看效果】

【下載】

http://download.csdn.net/detail/surfsky/8426563

【核心代碼】

 1 ScrollBar {
 2     id: root
 3     opacity: 0
 4     orientation: Qt.Vertical
 5 
 6     // 綁定到Flickable組件
 7     property Flickable target : Flickable{}
 8 
 9     // 位置
10     width: orientation==Qt.Vertical ? 10 : target.width-10
11     height: orientation==Qt.Vertical ? target.height-10 : 10
12     anchors.right: orientation==Qt.Vertical ? target.right : undefined
13     anchors.bottom: orientation==Qt.Vertical ? undefined : target.bottom
14 
15     // 滾動
16     position: orientation==Qt.Vertical ? target.visibleArea.yPosition   : target.visibleArea.xPosition
17     pageSize: orientation==Qt.Vertical ? target.visibleArea.heightRatio : target.visibleArea.widthRatio
18 
19 
20     // 移動時顯隱滾動軸
21     Connections{
22         target: root.target
23         onMovingVerticallyChanged: {
24             if (target.movingVertically)
25                 fadeIn.start();
26             else
27                 fadeOut.start();
28         }
29         onMovingHorizontallyChanged: {
30             if (target.movingHorizontally)
31                 fadeIn.start();
32             else
33                 fadeOut.start();
34         }
35     }
36     NumberAnimation { id:fadeIn;  target: root; properties: "opacity"; duration: 400; from:0; to:1 }
37     NumberAnimation { id:fadeOut; target: root; properties: "opacity"; duration: 400; from:1; to:0 }
38 }

 

【調用示例】

1     FlickableScrollBar {
2         target: view
3         orientation: Qt.Vertical
4     }