Meter.qml Example File

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 import QtQuick 1.0

 /* A meter component. */
 Rectangle {
     id: meter

     property real value: 0
     property real minValue: -1
     property real maxValue: 1
     property alias imageSize: meterImage.sourceSize

     function valueChanged(pValue) {
         value = pValue;
         scaleValueToAngle();
     }
     function scaleValueToAngle() {
         pointer.angle = (((value-minValue)/(maxValue-minValue))*
                           (pointer.angleMax-pointer.angleMin))+
                            pointer.angleMin;
     }

     color: "transparent"

     Image {
         id: meterImage

         smooth: true
         source: "./images/meterBG.png"
         anchors.fill: parent
     }

     Image {
         id:pointerShadow

         x: pointer.x - 2
         y: pointer.y - 2
         height: pointer.height
         smooth: true
         source: "./images/pointerShadow.png"
         transform: Rotation {
             origin.x: 2
             origin.y: height
             angle: -pointer.angle
         }
     }

     Image {
         id: pointer

         property real angle: 0
         property real angleMax: -45
         property real angleMin: 45

         height: parent.height*0.92
         transformOrigin: "Bottom"
         rotation: -angle
         smooth: true
         source: "./images/pointer.png"
         anchors {
             bottomMargin: 2
             bottom: parent.bottom;
             horizontalCenter: parent.horizontalCenter
         }

         Behavior on angle {
             SpringAnimation {
                 spring: 1.4
                 damping: 0.15
             }
         }
     }
 }