TachometerStyle.qml Example File

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 import QtQuick 2.2
 import QtQuick.Controls.Styles 1.4
 import QtQuick.Extras 1.4

 DashboardGaugeStyle {
     id: tachometerStyle
     tickmarkStepSize: 1
     labelStepSize: 1
     needleLength: toPixels(0.85)
     needleBaseWidth: toPixels(0.08)
     needleTipWidth: toPixels(0.03)

     tickmark: Rectangle {
         implicitWidth: toPixels(0.03)
         antialiasing: true
         implicitHeight: toPixels(0.08)
         color: styleData.index === 7 || styleData.index === 8 ? Qt.rgba(0.5, 0, 0, 1) : "#c8c8c8"
     }

     minorTickmark: null

     tickmarkLabel: Text {
         font.pixelSize: Math.max(6, toPixels(0.12))
         text: styleData.value
         color: styleData.index === 7 || styleData.index === 8 ? Qt.rgba(0.5, 0, 0, 1) : "#c8c8c8"
         antialiasing: true
     }

     background: Canvas {
         onPaint: {
             var ctx = getContext("2d");
             ctx.reset();
             paintBackground(ctx);

             ctx.beginPath();
             ctx.lineWidth = tachometerStyle.toPixels(0.08);
             ctx.strokeStyle = Qt.rgba(0.5, 0, 0, 1);
             var warningCircumference = maximumValueAngle - minimumValueAngle * 0.1;
             var startAngle = maximumValueAngle - 90;
             ctx.arc(outerRadius, outerRadius,
                 // Start the line in from the decorations, and account for the width of the line itself.
                 outerRadius - tickmarkInset - ctx.lineWidth / 2,
                 degToRad(startAngle - angleRange / 8 + angleRange * 0.015),
                 degToRad(startAngle - angleRange * 0.015), false);
             ctx.stroke();
         }

         Text {
             id: rpmText
             font.pixelSize: tachometerStyle.toPixels(0.3)
             text: rpmInt
             color: "white"
             horizontalAlignment: Text.AlignRight
             anchors.horizontalCenter: parent.horizontalCenter
             anchors.top: parent.verticalCenter
             anchors.topMargin: 20

             readonly property int rpmInt: valueSource.rpm
         }
         Text {
             text: "x1000"
             color: "white"
             font.pixelSize: tachometerStyle.toPixels(0.1)
             anchors.top: parent.top
             anchors.topMargin: parent.height / 4
             anchors.horizontalCenter: parent.horizontalCenter
         }
         Text {
             text: "RPM"
             color: "white"
             font.pixelSize: tachometerStyle.toPixels(0.1)
             anchors.top: rpmText.bottom
             anchors.horizontalCenter: parent.horizontalCenter
         }
     }
 }