使用ImageFiltered构件而不是BackdropFilter

Center(
        child: Stack(alignment: Alignment.center, children: [
          Image.network(
              "https://mojekooh.com/wp-content/uploads/2020/09/1024px-Matterhorn_from_Domh%C3%BCtte_-_2.jpg"),
          ClipRRect(
            child: ImageFiltered(
              imageFilter: ImageFilter.blur(sigmaX: 5, sigmaY: 5),
              child: Container(
                width: 200,
                height: 100,
                decoration: const BoxDecoration(
                    color: Color.fromARGB(33, 255, 0, 0),
                    shape: BoxShape.circle),
              ),
            ),
          )
        ]),
      ),

记住导入“dart：ui”

你可以模糊一个CircleAvatar，而不是模糊一个容器。

朋友们，我解决了这个问题：

Stack(alignment: Alignment.center, children: [
        Image.network(
            "https://mojekooh.com/wp-content/uploads/2020/09/1024px-Matterhorn_from_Domh%C3%BCtte_-_2.jpg"),
        ClipOval(
         clipper: CoustomCircle(),
          child: BackdropFilter(
           filter: ImageFilter.blur(sigmaX: 5, sigmaY: 5),
            child: Container(
              width: 200,
              height: 200,
              decoration: const BoxDecoration(
                  color: Color.fromARGB(57, 255, 0, 0),
                  shape: BoxShape.circle),
            ),
          ),
        )
      ]),

class CoustomCircle extends CustomClipper<Rect> {

  @override
  Rect getClip(size){
    return const Rect.fromLTWH(0, 0, 200, 200);
  }

@override
  bool shouldReclip(oldClipper){
  return true;
}
}