JoystickViewer.qml Example File

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  ** This file is part of the examples of the Qt Gamepad module
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  import QtQuick 2.0

  Item {
      width: 100
      height: 100

      property real xAxisValue: 0
      property real yAxisValue: 0

      onXAxisValueChanged: {
          joystickCanvas.requestPaint();
      }
      onYAxisValueChanged: {
          joystickCanvas.requestPaint()
      }

      Canvas {
          id: joystickCanvas
          anchors.fill: parent

          onPaint: {
              var context = joystickCanvas.getContext("2d")
              context.clearRect(0, 0, width, height);
              var targetX = (xAxisValue + 1) / 2 * width;
              var targetY = (yAxisValue + 1) / 2 * height;
              context.fillStyle = "red";
              context.beginPath();
              context.arc(targetX, targetY, 5, 0, 2 * Math.PI, false);
              context.closePath();
              context.fill();
          }
      }

  }