上效果

预期的是通过拖动一条边界线改变窗口大小，类似vscode里拖动效果。这个是简单的拖动实现

上代码：

import 'package:flutter/material.dart';

class MyDraggableViewDemo extends StatelessWidget {
  const MyDraggableViewDemo({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('MyDraggableViewDemo'),
        ),
        body: DraggableDemo(),
      ),
    );
  }
}

class DraggableDemo extends StatefulWidget {
  const DraggableDemo({super.key});

  @override
  State<StatefulWidget> createState() {
    return _DraggableDemoState();
  }
}

class _DraggableDemoState extends State<DraggableDemo> {
  double width = 200.0;
  double height = 200.0;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: GestureDetector(
        onPanUpdate: (details) {
          setState(() {
            width = width + details.delta.dx;
            height = height + details.delta.dy;
          });
        },
        child: Container(
          width: width,
          height: height,
          
          color: Colors.blue,
          child: Center(
            child: Text(
              '点击 拖动后改变窗口大小',
              style: TextStyle(color: Colors.white),
            ),
          ),
        ),
      ),
    );
  }
}

所以预期的边界线效果，应该是对边界线进行处理，然后和关联的 widget 进行联动，
下一篇见

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