Qt 5.6 | Qt Quick Extras | Qt Quick Extras - Dashboard | TurnIndicator.qml Example File

Qt 5.6.2 Reference Documentation

# TurnIndicator.qml Example File

dashboard/qml/TurnIndicator.qml

      /****************************************************************************
      **
      ** Copyright (C) 2015 The Qt Company Ltd.
      ** Contact: http://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** You may use this file under the terms of the BSD license as follows:
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      import QtQuick 2.2

      Item {
          // This enum is actually keyboard-related, but it serves its purpose
          // as an indication of direction for us.
          property int direction: Qt.LeftArrow
          property bool on: false

          property bool flashing: false

          scale: direction === Qt.LeftArrow ? 1 : -1

          Timer {
              id: flashTimer
              interval: 500
              running: on
              repeat: true
              onTriggered: flashing = !flashing
          }

          function paintOutlinePath(ctx) {
              ctx.beginPath();
              ctx.moveTo(0, height * 0.5);
              ctx.lineTo(0.6 * width, 0);
              ctx.lineTo(0.6 * width, height * 0.28);
              ctx.lineTo(width, height * 0.28);
              ctx.lineTo(width, height * 0.72);
              ctx.lineTo(0.6 * width, height * 0.72);
              ctx.lineTo(0.6 * width, height);
              ctx.lineTo(0, height * 0.5);
          }

          Canvas {
              id: backgroundCanvas
              anchors.fill: parent

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

                  paintOutlinePath(ctx);

                  ctx.lineWidth = 1;
                  ctx.strokeStyle = "black";
                  ctx.stroke();
              }
          }

          Canvas {
              id: foregroundCanvas
              anchors.fill: parent
              visible: on && flashing

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

                  paintOutlinePath(ctx);

                  ctx.fillStyle = "green";
                  ctx.fill();
              }
          }
      }