​​​​​​

• 创建 package

flutter create --template=package mypackage

package代码如下：

        创建hello_world.dart        

///HelloWorld返回hello world 拼接param
class HelloWorld {String helloWorld(String param) => "hello world ${param}";
}

        导出hello_world.dart

library mypackage;export 'src/hello_world.dart';

• 创建flutter项目

flutter create myflutter

• myflutter pubspec.yaml中引入myPackage

dependencies:flutter:sdk: fluttercupertino_icons: ^1.0.2mypackage:path: /Users/administrator/Desktop/workspace/mypackage

• myflutter中调用

import 'package:flutter/material.dart';
import 'package:mypackage/mypackage.dart';void main() {runApp(const MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});@overrideWidget build(BuildContext context) {return MaterialApp(title: 'Flutter Demo',theme: ThemeData(primarySwatch: Colors.blue,),home: const MyHomePage(title: 'Flutter Demo Home Page'),);}
}class MyHomePage extends StatefulWidget {const MyHomePage({super.key, required this.title});final String title;@overrideState<MyHomePage> createState() => _MyHomePageState();
}class _MyHomePageState extends State<MyHomePage> {String helloWorld ="";@overridevoid initState() {super.initState();helloWorld = HelloWorld().helloWorld("我是拼接的字符串!");}@overrideWidget build(BuildContext context) {return Scaffold(appBar: AppBar(title: Text("你好世界"),),body: Center(child: Column(mainAxisAlignment: MainAxisAlignment.center,children: <Widget>[Text('${helloWorld}',style: TextStyle(fontWeight: FontWeight.bold,fontSize: 26),)],),),);}
}

• 效果展示