paint method

  1. @override
void paint(
  1. Canvas canvas,
  2. Size size
)
override

Called whenever the object needs to paint. The given Canvas has its coordinate space configured such that the origin is at the top left of the box. The area of the box is the size of the size argument.

Paint operations should remain inside the given area. Graphical operations outside the bounds may be silently ignored, clipped, or not clipped. It may sometimes be difficult to guarantee that a certain operation is inside the bounds (e.g., drawing a rectangle whose size is determined by user inputs). In that case, consider calling Canvas.clipRect at the beginning of paint so everything that follows will be guaranteed to only draw within the clipped area.

Implementations should be wary of correctly pairing any calls to Canvas.save/Canvas.saveLayer and Canvas.restore, otherwise all subsequent painting on this canvas may be affected, with potentially hilarious but confusing results.

To paint text on a Canvas, use a TextPainter.

To paint an image on a Canvas:

  1. Obtain an ImageStream, for example by calling ImageProvider.resolve on an AssetImage or NetworkImage object.

  2. Whenever the ImageStream's underlying ImageInfo object changes (see ImageStream.addListener), create a new instance of your custom paint delegate, giving it the new ImageInfo object.

  3. In your delegate's paint method, call the Canvas.drawImage, Canvas.drawImageRect, or Canvas.drawImageNine methods to paint the ImageInfo.image object, applying the ImageInfo.scale value to obtain the correct rendering size.

Implementation

@override
void paint(Canvas canvas, Size size) {
  final scaleX = size.width / 20.0;
  final scaleY = size.height / 20.0;
  final scale = math.min(scaleX, scaleY);

  final translationX = (size.width - 20.0 * scale) / 2 - 2.0 * scale;
  final translationY = (size.height - 20.0 * scale) / 2 - 2.0 * scale;

  final path = Path();
  final paint = Paint()..color = color;

  path.moveTo(
    14.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.lineTo(
    10.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.cubicTo(
    9.447715250169207 * scale + translationX,
    9.0 * scale + translationY,
    9.0 * scale + translationX,
    9.447715250169207 * scale + translationY,
    9.0 * scale + translationX,
    10.0 * scale + translationY,
  );

  path.lineTo(
    9.0 * scale + translationX,
    14.0 * scale + translationY,
  );

  path.cubicTo(
    9.0 * scale + translationX,
    14.552284749830793 * scale + translationY,
    9.447715250169207 * scale + translationX,
    15.0 * scale + translationY,
    10.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.lineTo(
    14.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.cubicTo(
    14.552284749830793 * scale + translationX,
    15.0 * scale + translationY,
    15.0 * scale + translationX,
    14.552284749830793 * scale + translationY,
    15.0 * scale + translationX,
    14.0 * scale + translationY,
  );

  path.lineTo(
    15.0 * scale + translationX,
    10.0 * scale + translationY,
  );

  path.cubicTo(
    15.0 * scale + translationX,
    9.447715250169207 * scale + translationY,
    14.552284749830793 * scale + translationX,
    9.0 * scale + translationY,
    14.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.close();

  path.moveTo(
    13.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.lineTo(
    11.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.lineTo(
    11.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.lineTo(
    13.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.close();

  path.moveTo(
    21.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.cubicTo(
    21.552284749830793 * scale + translationX,
    13.0 * scale + translationY,
    22.0 * scale + translationX,
    12.552284749830793 * scale + translationY,
    22.0 * scale + translationX,
    12.0 * scale + translationY,
  );

  path.cubicTo(
    22.0 * scale + translationX,
    11.447715250169207 * scale + translationY,
    21.552284749830793 * scale + translationX,
    11.0 * scale + translationY,
    21.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.lineTo(
    19.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.lineTo(
    19.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.lineTo(
    21.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.cubicTo(
    21.552284749830793 * scale + translationX,
    9.0 * scale + translationY,
    22.0 * scale + translationX,
    8.552284749830793 * scale + translationY,
    22.0 * scale + translationX,
    8.0 * scale + translationY,
  );

  path.cubicTo(
    22.0 * scale + translationX,
    7.447715250169207 * scale + translationY,
    21.552284749830793 * scale + translationX,
    7.0 * scale + translationY,
    21.0 * scale + translationX,
    7.0 * scale + translationY,
  );

  path.lineTo(
    18.82 * scale + translationX,
    7.0 * scale + translationY,
  );

  path.cubicTo(
    18.517618325357592 * scale + translationX,
    6.1506843235616415 * scale + translationY,
    17.849316391694096 * scale + translationX,
    5.482382389898145 * scale + translationY,
    17.00000050663948 * scale + translationX,
    5.18000015437603 * scale + translationY,
  );

  path.lineTo(
    17.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.cubicTo(
    17.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    16.552284749830793 * scale + translationX,
    2.0 * scale + translationY,
    16.0 * scale + translationX,
    2.0 * scale + translationY,
  );

  path.cubicTo(
    15.447715250169207 * scale + translationX,
    2.0 * scale + translationY,
    15.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    15.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.lineTo(
    15.0 * scale + translationX,
    5.0 * scale + translationY,
  );

  path.lineTo(
    13.0 * scale + translationX,
    5.0 * scale + translationY,
  );

  path.lineTo(
    13.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.cubicTo(
    13.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    12.552284749830793 * scale + translationX,
    2.0 * scale + translationY,
    12.0 * scale + translationX,
    2.0 * scale + translationY,
  );

  path.cubicTo(
    11.447715250169207 * scale + translationX,
    2.0 * scale + translationY,
    11.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    11.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.lineTo(
    11.0 * scale + translationX,
    5.0 * scale + translationY,
  );

  path.lineTo(
    9.0 * scale + translationX,
    5.0 * scale + translationY,
  );

  path.lineTo(
    9.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.cubicTo(
    9.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    8.552284749830793 * scale + translationX,
    2.0 * scale + translationY,
    8.0 * scale + translationX,
    2.0 * scale + translationY,
  );

  path.cubicTo(
    7.447715250169207 * scale + translationX,
    2.0 * scale + translationY,
    7.0 * scale + translationX,
    2.4477152501692068 * scale + translationY,
    7.0 * scale + translationX,
    3.0 * scale + translationY,
  );

  path.lineTo(
    7.0 * scale + translationX,
    5.18 * scale + translationY,
  );

  path.cubicTo(
    6.1506843235616415 * scale + translationX,
    5.482382389898145 * scale + translationY,
    5.482382389898145 * scale + translationX,
    6.1506843235616415 * scale + translationY,
    5.18000015437603 * scale + translationX,
    7.000000208616257 * scale + translationY,
  );

  path.lineTo(
    3.0 * scale + translationX,
    7.0 * scale + translationY,
  );

  path.cubicTo(
    2.4477152501692068 * scale + translationX,
    7.0 * scale + translationY,
    2.0 * scale + translationX,
    7.447715250169207 * scale + translationY,
    2.0 * scale + translationX,
    8.0 * scale + translationY,
  );

  path.cubicTo(
    2.0 * scale + translationX,
    8.552284749830793 * scale + translationY,
    2.4477152501692068 * scale + translationX,
    9.0 * scale + translationY,
    3.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.lineTo(
    5.0 * scale + translationX,
    9.0 * scale + translationY,
  );

  path.lineTo(
    5.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.lineTo(
    3.0 * scale + translationX,
    11.0 * scale + translationY,
  );

  path.cubicTo(
    2.4477152501692068 * scale + translationX,
    11.0 * scale + translationY,
    2.0 * scale + translationX,
    11.447715250169207 * scale + translationY,
    2.0 * scale + translationX,
    12.0 * scale + translationY,
  );

  path.cubicTo(
    2.0 * scale + translationX,
    12.552284749830793 * scale + translationY,
    2.4477152501692068 * scale + translationX,
    13.0 * scale + translationY,
    3.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.lineTo(
    5.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.lineTo(
    5.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.lineTo(
    3.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.cubicTo(
    2.4477152501692068 * scale + translationX,
    15.0 * scale + translationY,
    2.0 * scale + translationX,
    15.447715250169207 * scale + translationY,
    2.0 * scale + translationX,
    16.0 * scale + translationY,
  );

  path.cubicTo(
    2.0 * scale + translationX,
    16.552284749830793 * scale + translationY,
    2.4477152501692068 * scale + translationX,
    17.0 * scale + translationY,
    3.0 * scale + translationX,
    17.0 * scale + translationY,
  );

  path.lineTo(
    5.18 * scale + translationX,
    17.0 * scale + translationY,
  );

  path.cubicTo(
    5.482382389898145 * scale + translationX,
    17.849316391694096 * scale + translationY,
    6.1506843235616415 * scale + translationX,
    18.517618325357592 * scale + translationY,
    7.000000208616257 * scale + translationX,
    18.82000056087971 * scale + translationY,
  );

  path.lineTo(
    7.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.cubicTo(
    7.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    7.447715250169207 * scale + translationX,
    22.0 * scale + translationY,
    8.0 * scale + translationX,
    22.0 * scale + translationY,
  );

  path.cubicTo(
    8.552284749830793 * scale + translationX,
    22.0 * scale + translationY,
    9.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    9.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.lineTo(
    9.0 * scale + translationX,
    19.0 * scale + translationY,
  );

  path.lineTo(
    11.0 * scale + translationX,
    19.0 * scale + translationY,
  );

  path.lineTo(
    11.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.cubicTo(
    11.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    11.447715250169207 * scale + translationX,
    22.0 * scale + translationY,
    12.0 * scale + translationX,
    22.0 * scale + translationY,
  );

  path.cubicTo(
    12.552284749830793 * scale + translationX,
    22.0 * scale + translationY,
    13.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    13.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.lineTo(
    13.0 * scale + translationX,
    19.0 * scale + translationY,
  );

  path.lineTo(
    15.0 * scale + translationX,
    19.0 * scale + translationY,
  );

  path.lineTo(
    15.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.cubicTo(
    15.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    15.447715250169207 * scale + translationX,
    22.0 * scale + translationY,
    16.0 * scale + translationX,
    22.0 * scale + translationY,
  );

  path.cubicTo(
    16.552284749830793 * scale + translationX,
    22.0 * scale + translationY,
    17.0 * scale + translationX,
    21.552284749830793 * scale + translationY,
    17.0 * scale + translationX,
    21.0 * scale + translationY,
  );

  path.lineTo(
    17.0 * scale + translationX,
    18.82 * scale + translationY,
  );

  path.cubicTo(
    17.849316391694096 * scale + translationX,
    18.517618325357592 * scale + translationY,
    18.517618325357592 * scale + translationX,
    17.849316391694096 * scale + translationY,
    18.82000056087971 * scale + translationX,
    17.00000050663948 * scale + translationY,
  );

  path.lineTo(
    21.0 * scale + translationX,
    17.0 * scale + translationY,
  );

  path.cubicTo(
    21.552284749830793 * scale + translationX,
    17.0 * scale + translationY,
    22.0 * scale + translationX,
    16.552284749830793 * scale + translationY,
    22.0 * scale + translationX,
    16.0 * scale + translationY,
  );

  path.cubicTo(
    22.0 * scale + translationX,
    15.447715250169207 * scale + translationY,
    21.552284749830793 * scale + translationX,
    15.0 * scale + translationY,
    21.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.lineTo(
    19.0 * scale + translationX,
    15.0 * scale + translationY,
  );

  path.lineTo(
    19.0 * scale + translationX,
    13.0 * scale + translationY,
  );

  path.close();

  path.moveTo(
    17.0 * scale + translationX,
    16.0 * scale + translationY,
  );

  path.cubicTo(
    17.0 * scale + translationX,
    16.552284749830793 * scale + translationY,
    16.552284749830793 * scale + translationX,
    17.0 * scale + translationY,
    16.0 * scale + translationX,
    17.0 * scale + translationY,
  );

  path.lineTo(
    8.0 * scale + translationX,
    17.0 * scale + translationY,
  );

  path.cubicTo(
    7.447715250169207 * scale + translationX,
    17.0 * scale + translationY,
    7.0 * scale + translationX,
    16.552284749830793 * scale + translationY,
    7.0 * scale + translationX,
    16.0 * scale + translationY,
  );

  path.lineTo(
    7.0 * scale + translationX,
    8.0 * scale + translationY,
  );

  path.cubicTo(
    7.0 * scale + translationX,
    7.447715250169207 * scale + translationY,
    7.447715250169207 * scale + translationX,
    7.0 * scale + translationY,
    8.0 * scale + translationX,
    7.0 * scale + translationY,
  );

  path.lineTo(
    16.0 * scale + translationX,
    7.0 * scale + translationY,
  );

  path.cubicTo(
    16.552284749830793 * scale + translationX,
    7.0 * scale + translationY,
    17.0 * scale + translationX,
    7.447715250169207 * scale + translationY,
    17.0 * scale + translationX,
    8.0 * scale + translationY,
  );

  path.close();

  canvas.drawPath(path, paint);
}