返回页面数据-Flutter

返回页面数据

• 效果
  

• 源代码

  import 'package:flutter/material.dart';
  void main() {
    runApp(MaterialApp(
      home: First(),
    ));
  }
  class First extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return Scaffold(
        appBar: AppBar(
          title: Text("异步请求和等待"),
        ),
        body: Center(
          child: MyButton()
        ),
      );
    }
  }
  //单独声明按钮，否则SnackBar无效果
  class MyButton extends StatelessWidget{
    @override
    Widget build(BuildContext context) {
      // TODO: implement build
      return RaisedButton(
        child: Text("Go"),
        onPressed: (){
          _fun(context);
        },
      );
    }
  }
  _fun(BuildContext context) async {//异步处理
    //await与async相伴
    final result = await Navigator.push(
      context,
      // Create the SelectionScreen in the next step.
      MaterialPageRoute(builder: (context) => Second()),
    );
    //移除上一个SnackBar
    Scaffold.of(context).removeCurrentSnackBar();
    //生成一个SnackBar并把接收的信息展示
    Scaffold.of(context).showSnackBar(SnackBar(content: Text("$result"),));
  }
  class Second extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return Scaffold(
        appBar: AppBar(
          title: Text("返回下列数据"),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              Center(child: RaisedButton(
                child: Text("阿腾木的小世界"),
                onPressed: (){
                  Navigator.pop(context,'阿腾木的小世界');
                },
              )),
              Center(child: RaisedButton(
                child: Text("ccatom.com"),
                onPressed: ()=>Navigator.pop(context,"ccatom.com"),
              )
              )],
          ),
        )
  
      );
    }
  }