代码

import 'package:flutter/material.dart';

class WrapDemo extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      child: Wrap(
        alignment: WrapAlignment.center,
        spacing: 10,
        runSpacing: 20,
        children: [MyWidget(), MyWidget(), MyWidget(), MyWidget()],
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      width: 100,
      height: 100,
      color: Colors.green,
    );
  }
}

修改后效果