Stack 层叠布局

main.dart

import 'package:flutter/material.dart';

void main() {
  runApp(
    MaterialApp(
      title: "Stack层叠布局示例",
      home: MyApp(),
    ),
  );
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    var stack = Stack(
      alignment: Alignment.topLeft,
      children: <Widget>[
        CircleAvatar(
          backgroundImage:
              NetworkImage("https://static.lidong.me/upload/XjGwvaVAI.png"),
          radius: 100.0,
        ),
        Container(
          decoration: BoxDecoration(
            color: Colors.black38,
          ),
          child: Text(
            "哈哈哈哈",
            style: TextStyle(
              fontSize: 22.0,
              fontWeight: FontWeight.bold,
              color: Colors.white,
            ),
          ),
        )
      ],
    );
    return Scaffold(
      appBar: AppBar(
        title: Text("Stack层叠布局示例"),
      ),
      body: Center(
        child: stack,
      ),
    );
  }
}