ScrollBar.qml Example File | Qt 5.12

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- ScrollBar.qml Example File
- Qt 5.12.10 Reference Documentation

# ScrollBar.qml Example File

demos/rssnews/content/ScrollBar.qml

     /****************************************************************************
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     ** Contact: https://www.qt.io/licensing/
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     ** This file is part of the examples of the Qt Toolkit.
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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 }
         }
     }