Qt 5.9 | Qt Quick Extras | Qt Quick Extras - Dashboard | TurnIndicator.qml Example File

Qt 5.9.9 Reference Documentation

# TurnIndicator.qml Example File

dashboard/qml/TurnIndicator.qml

      /****************************************************************************
      **
      ** Copyright (C) 2016 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      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();
              }
          }
      }