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
          }
      }
  }