【Flutter】自定义 Flutter 组件 ( 创建自定义 StatelessWidget、StatefulWidget 组件 | 调用自定义组件 )（二）

Can't define a const constructor for a class with non-final fields. (Documentation)  Try making all of the fields final, or removing the keyword 'const' from the constructor.

abstract class StatelessWidget extends Widget {
}

@immutable
abstract class Widget extends DiagnosticableTree {
}

StudentStatelessWidget(
    name: "Tom",
    age: 18
),
StudentStatefulWidget(
    name: "Jerry",
    age: 16
),

import 'package:flutter/material.dart';
import 'package:flutter_widget/widget/student_stateful_widget.dart';
import 'package:flutter_widget/widget/student_stateless_widget.dart';
void main() {
  runApp(MyApp());
}
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}
class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, required this.title}) : super(key: key);
  final String title;
  @override
  _MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            StudentStatelessWidget(
                name: "Tom",
                age: 18
            ),
            StudentStatefulWidget(
                name: "Jerry",
                age: 16
            ),
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}