Flutter 缩放示例

class ScaleWidget extends StatefulWidget {
  const ScaleWidget({Key? key, required this.title}) : super(key: key);

  final String title;

  @override
  State<ScaleWidget> createState() {
    return ScaleState();
  }
}

class ScaleState extends State<ScaleWidget> {
  double _width = 150.0; //通过修改图片宽度来达到缩放效果

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: Center(
        child: GestureDetector(
          //指定宽度，高度自适应
          child: Image.asset("images/avatar.png", width: _width),
          onScaleUpdate: (ScaleUpdateDetails details) {
            setState(() {
              //缩放倍数在0.8到10倍之间
              _width=200*details.scale.clamp(.5, 10.0);
            });
          },
        ),
      ),
    );
  }
}

缩放	正常	放大