Flutter 剪裁（Clip）

🔥 ClipOval 🔥

子组件为正方形时剪裁成内贴圆形；为矩形时，剪裁成内贴椭圆

裁剪纯色背景

ClipOval(child: Container(width: 300.w,height: 300.w,decoration: const BoxDecoration(color: Colors.red),),),

裁剪背景图片

裁剪前

ClipOval(clipBehavior: Clip.none,child: Image.asset('assets/demo/message.png',width: 300.w,)),

裁剪后

ClipOval(child: Image.asset('assets/demo/message.png',width: 300.w,)),

自定义裁剪区域一

ClipOval(clipper: ClipperOvalPath(),child: Image.asset('assets/demo/message.png',width: 300.w,)),

class ClipperOvalPath extends CustomClipper<Rect> {@overrideRect getClip(Size size) {return Rect.fromLTRB(0, 0, size.width - 100.w, size.height - 100.w);}@overridebool shouldReclip(CustomClipper<Rect> oldClipper) {return false;}
}

自定义裁剪区域二

class ClipperOvalPath extends CustomClipper<Rect> {@overrideRect getClip(Size size) {return Rect.fromLTRB(0, 0, size.width - 50.w, size.height - 100.w);}@overridebool shouldReclip(CustomClipper<Rect> oldClipper) {return false;}
}

自定义裁剪区域三

class ClipperOvalPath extends CustomClipper<Rect> {@overrideRect getClip(Size size) {return Rect.fromLTRB(0, 0, size.width - 50.w, size.height - 200.w);}@overridebool shouldReclip(CustomClipper<Rect> oldClipper) {return false;}
}

🔥 ClipRRect 🔥

将子组件剪裁为圆角矩形

纯色背景裁剪为圆角矩形

ClipRRect(borderRadius: BorderRadius.circular(50.w),child: Container(width: 300.w,height: 300.w,decoration: const BoxDecoration(color: Colors.red),),)

将图片裁剪为圆角矩形

ClipRRect(clipper: ClipperOvalPath(),child: Image.asset('assets/demo/message.png',)),

class ClipperOvalPath extends CustomClipper<RRect> {@overrideRRect getClip(Size size) {return RRect.fromLTRBR(0, 0, size.width-100.w, size.height-140.w,Radius.circular(20.w));}@overridebool shouldReclip(covariant CustomClipper<RRect> oldClipper) {return true;}
}

自定义裁剪区域导致裁剪图片为圆角矩形失败

class ClipperOvalPath extends CustomClipper<RRect> {@overrideRRect getClip(Size size) {return RRect.fromLTRBR(0, 0, size.width-100.w, size.height-80.w,Radius.circular(20.w));}@overridebool shouldReclip(covariant CustomClipper<RRect> oldClipper) {return true;}
}

🔥 ClipRect 🔥

默认剪裁掉子组件布局空间之外的绘制内容（溢出部分剪裁）

 Align(alignment: Alignment.topLeft,widthFactor: .5, //宽度设为原来宽度一半，另一半会溢出child: Image.asset("assets/demo/message.png"),),ClipRect(//将溢出部分剪裁child: Align(alignment: Alignment.topLeft,widthFactor: .5,//宽度设为原来宽度一半child: Image.asset("assets/demo/message.png"),),),

🔥 ClipPath 🔥

按照自定义的路径剪裁

设置了剪切的区域

Image.asset("assets/demo/message.png"),DecoratedBox(decoration: const BoxDecoration(color: Colors.red),child: ClipRect(clipper: MyClipper(), //使用自定义的clipperchild: Image.asset("assets/demo/message.png")),)

class MyClipper extends CustomClipper<Rect> {@overrideRect getClip(Size size) => const Rect.fromLTWH(10.0, 15.0, 100.0, 200.0);@overridebool shouldReclip(CustomClipper<Rect> oldClipper) => false;
}