Qt 5.6 | Qt Quick | Qt Quick Examples - Canvas | smile.qml Example File

Qt 5.6.3 Reference Documentation

# smile.qml Example File

canvas/smile/smile.qml

      /****************************************************************************
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      ** Contact: http://www.qt.io/licensing/
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      ** This file is part of the examples of the Qt Toolkit.
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      import QtQuick 2.0
      import "../contents"
      import "../../shared"

      Item {
          id: container
          width: 320
          height: 480

          Column {
              spacing: 6
              anchors.fill: parent
              anchors.topMargin: 12

              Text {
                  font.pointSize: 24
                  font.bold: true
                  text: "Smile with arcs"
                  anchors.horizontalCenter: parent.horizontalCenter
                  color: "#777"
              }

              Canvas {
                  id: canvas
                  width: 320
                  height: parent.height - controls.height
                  antialiasing: true

                  property color strokeStyle:  Qt.darker(fillStyle, 1.6)
                  property color fillStyle: "#e0c31e" // yellow
                  property int lineWidth: lineWidthCtrl.value
                  property bool fill: true
                  property bool stroke: true
                  property real scale : scaleCtrl.value
                  property real rotate : rotateCtrl.value

                  onLineWidthChanged:requestPaint();
                  onFillChanged:requestPaint();
                  onStrokeChanged:requestPaint();
                  onScaleChanged:requestPaint();
                  onRotateChanged:requestPaint();

                  onPaint: {
                      var ctx = canvas.getContext('2d');
                      var originX = 85
                      var originY = 75
                      ctx.save();
                      ctx.clearRect(0, 0, canvas.width, canvas.height);
                      ctx.translate(originX, originX);
                      ctx.globalAlpha = canvas.alpha;
                      ctx.strokeStyle = canvas.strokeStyle;
                      ctx.fillStyle = canvas.fillStyle;
                      ctx.lineWidth = canvas.lineWidth;

                      ctx.translate(originX, originY)
                      ctx.scale(canvas.scale, canvas.scale);
                      ctx.rotate(canvas.rotate);
                      ctx.translate(-originX, -originY)

                      ctx.beginPath();
                      ctx.moveTo(75 + 50  * Math.cos(0),
                                 75 - 50  * Math.sin(Math.PI*2));
                      ctx.arc(75,75,50,0,Math.PI*2,true); // Outer circle
                      ctx.moveTo(75,70);
                      ctx.arc(75,70,35,0,Math.PI,false);   // Mouth (clockwise)
                      ctx.moveTo(60,65);
                      ctx.arc(60,65,5,0,Math.PI*2,true);  // Left eye
                      ctx.moveTo(90 + 5  * Math.cos(0),
                                 65 - 5  * Math.sin(Math.PI*2));
                      ctx.moveTo(90,65);
                      ctx.arc(90,65,5,0,Math.PI*2,true);  // Right eye
                      ctx.closePath();
                      if (canvas.fill)
                          ctx.fill();
                      if (canvas.stroke)
                          ctx.stroke();
                      ctx.restore();
                  }
              }
          }
          Column {
              id: controls
              anchors.bottom: parent.bottom
              anchors.bottomMargin: 12
              Slider {id: lineWidthCtrl ; min: 1 ; max: 10 ; init: 2 ; name: "Outline"}
              Slider {id: scaleCtrl ; min: 0.1 ; max: 10 ; init: 1 ; name: "Scale"}
              Slider {id: rotateCtrl ; min: 0 ; max: Math.PI*2 ; init: 0 ; name: "Rotate"}
          }
      }