src/widgets/ZoomControl.qml

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0050
0051 import QtQuick 2.0
0052 import QtMultimedia 5.0
0053
0054 Item {
0055     id : zoomControl
0056     property real currentZoom : 1
0057     property real maximumZoom : 1
0058     signal zoomTo(real value)
0059
0060     visible: zoomControl.maximumZoom > 1
0061
0062     MouseArea {
0063         id : mouseArea
0064         anchors.fill: parent
0065
0066         property real initialZoom : 0
0067         property real initialPos : 0
0068
0069         onPressed: {
0070             initialPos = mouseY
0071             initialZoom = zoomControl.currentZoom
0072         }
0073
0074         onPositionChanged: {
0075             if (pressed) {
0076                 var target = initialZoom * Math.pow(5, (initialPos-mouseY)/zoomControl.height);
0077                 target = Math.max(1, Math.min(target, zoomControl.maximumZoom))
0078                 zoomControl.zoomTo(target)
0079             }
0080         }
0081     }
0082
0083     Item {
0084         id : bar
0085         x : 16
0086         y : parent.height/4
0087         width : 24
0088         height : parent.height/2
0089
0090         Rectangle {
0091             anchors.fill: parent
0092
0093             smooth: true
0094             radius: 8
0095             border.color: "white"
0096             border.width: 2
0097             color: "black"
0098             opacity: 0.3
0099         }
0100
0101         Rectangle {
0102             id: groove
0103             x : 0
0104             y : parent.height * (1.0 - (zoomControl.currentZoom-1.0) / (zoomControl.maximumZoom-1.0))
0105             width: parent.width
0106             height: parent.height - y
0107             smooth: true
0108             radius: 8
0109             color: "white"
0110             opacity: 0.5
0111         }
0112
0113         Text {
0114             id: zoomText
0115             anchors {
0116                 left: bar.right; leftMargin: 16
0117             }
0118             y: Math.min(parent.height - height, Math.max(0, groove.y - height / 2))
0119             text: "x" + Math.round(zoomControl.currentZoom * 100) / 100
0120             font.bold: true
0121             color: "white"
0122             style: Text.Raised; styleColor: "black"
0123             opacity: 0.85
0124             font.pixelSize: 18
0125         }
0126     }
0127 }