Flutter 裁剪类组件 最全总结

ClipRect(
  child: Align(
    alignment: Alignment.topCenter,heightFactor: 0.5,child: Container(
      height: 150,width: 150,child: Image.asset(
        'images/1.png',fit: BoxFit.cover,),)

• none：不裁剪，系统默认值，如果子组件不超出边界，此值没有任何性能消耗。
• hardEdge：裁剪但不应用抗锯齿，速度比none慢一点，但比其他方式快。
• antiAlias：裁剪而且抗锯齿，此方式看起来更平滑，比antiAliasWithSaveLayer快，比hardEdge慢，通常用于处理圆形和弧形裁剪。
• antiAliasWithSaveLayer：裁剪、抗锯齿而且有一个缓冲区，此方式很慢，用到的情况比较少。

ClipRRect(
  borderRadius: BorderRadius.circular(20),child: Container(
    height: 150,child: Image.asset(
      'images/1.png',)

ClipOval(
  child: Container(
    height: 150,width: 250,)

ClipPath.shape(
  shape: StadiumBorder(),)

• CircleBorder：圆形。

@override
Widget build(BuildContext context) {
  return Center(
    child: ClipPath(
      clipper: TrianglePath(),child: Container(
        height: 150,child: Image.asset(
          'images/1.png',);
}

class TrianglePath extends CustomClipper<Path>{
  @override
  Path getClip(Size size) {
    var path = Path();
    path.moveTo(size.width/2,0);
    path.lineTo(0,size.height);
    path.lineTo(size.width,size.height);
    return path;
  }

  @override
  bool shouldReclip(CustomClipper<Path> oldClipper) {
    return true;
  }
}

class StarPath extends CustomClipper<Path> {
  StarPath({this.scale = 2.5});

  final double scale;

  double perDegree = 36;

  /// 角度转弧度公式
  double degree2Radian(double degree) {
    return (pi * degree / 180);
  }

  @override
  Path getClip(Size size) {
    var R = min(size.width / 2,size.height / 2);
    var r = R / scale;
    var x = size.width / 2;
    var y = size.height / 2;

    var path = Path();
    path.moveTo(x,y - R);
    path.lineTo(x - sin(degree2Radian(perDegree)) * r,y - cos(degree2Radian(perDegree)) * r);
    path.lineTo(x - sin(degree2Radian(perDegree * 2)) * R,y - cos(degree2Radian(perDegree * 2)) * R);
    path.lineTo(x - sin(degree2Radian(perDegree * 3)) * r,y - cos(degree2Radian(perDegree * 3)) * r);
    path.lineTo(x - sin(degree2Radian(perDegree * 4)) * R,y - cos(degree2Radian(perDegree * 4)) * R);
    path.lineTo(x - sin(degree2Radian(perDegree * 5)) * r,y - cos(degree2Radian(perDegree * 5)) * r);
    path.lineTo(x - sin(degree2Radian(perDegree * 6)) * R,y - cos(degree2Radian(perDegree * 6)) * R);
    path.lineTo(x - sin(degree2Radian(perDegree * 7)) * r,y - cos(degree2Radian(perDegree * 7)) * r);
    path.lineTo(x - sin(degree2Radian(perDegree * 8)) * R,y - cos(degree2Radian(perDegree * 8)) * R);
    path.lineTo(x - sin(degree2Radian(perDegree * 9)) * r,y - cos(degree2Radian(perDegree * 9)) * r);
    path.lineTo(x - sin(degree2Radian(perDegree * 10)) * R,y - cos(degree2Radian(perDegree * 10)) * R);
    return path;
  }

  @override
  bool shouldReclip(StarPath oldClipper) {
    return oldClipper.scale != this.scale;
  }
}

class StartClip extends StatefulWidget {
  @override
  State<StatefulWidget> createState() => _StartClipState();
}

class _StartClipState extends State<StartClip>
    with SingleTickerProviderStateMixin {
  AnimationController _controller;
  Animation _animation;

  @override
  void initState() {
    _controller =
        AnimationController(duration: Duration(seconds: 2),vsync: this)
          ..addStatusListener((status) {
            if (status == AnimationStatus.completed) {
              _controller.reverse();
            } else if (status == AnimationStatus.dismissed) {
              _controller.forward();
            }
          });
    _animation = Tween(begin: 1.0,end: 4.0).animate(_controller);
    _controller.forward();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: AnimatedBuilder(
          animation: _animation,builder: (context,child) {
            return ClipPath(
              clipper: StarPath(scale: _animation.value),child: Container(
                height: 150,color: Colors.red,);
          }),);
  }
}

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