Qt 5.7 | Qt Quick Extras | Qt Quick Extras - Dashboard | TachometerStyle.qml Example File

Qt 5.7.1 Reference Documentation

# TachometerStyle.qml Example File

dashboard/qml/TachometerStyle.qml

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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
              }
          }
      }