南宁市住房建设局网站,在线域名ip查询,wordpress缓存方案,用户界面设计软件当继承StatelessWidget组件时#xff0c;在组件中更新数据时页面不会立即刷新。
如果继承StatefulWidget时#xff0c;只要在setState方法中更新数据后页面会实时更新数据。 Flutter有状态组件StatefulWidget 完整代码#xff1a;
import package:flutter/material.dart;v…当继承StatelessWidget组件时在组件中更新数据时页面不会立即刷新。
如果继承StatefulWidget时只要在setState方法中更新数据后页面会实时更新数据。 Flutter有状态组件StatefulWidget 完整代码
import package:flutter/material.dart;void main() {runApp(const MyApp());
}class MyApp extends StatelessWidget {const MyApp({super.key});overrideWidget build(BuildContext context) {return MaterialApp(theme: ThemeData(primarySwatch: Colors.blue),home: Scaffold(appBar: AppBar(title: const Text(Flutter),),body: const MyHomePage(),),);}
}class MyHomePage extends StatelessWidget {const MyHomePage({Key? key}) : super(key: key);overrideWidget build(BuildContext context) {return const _HomePageState();}
}///StatefulWidget:状态组件改变页面数据状态
class _HomePageState extends StatefulWidget {const _HomePageState();overrideState_HomePageState createState() _HomePageStateState();
}class _HomePageStateState extends State_HomePageState {final ListString _list [数据一, 数据二, 数据三];overrideWidget build(BuildContext context) {return Scaffold(body: ListView(children: _list.map((v) {return ListTile(title: Text(v));}).toList(),),floatingActionButton: FloatingActionButton(onPressed: () {setState(() {_list.add(新增数据);});},child: const Icon(Icons.add),),);}
}
