您可以使用 回调函数 来实现此目的。请参考下面的代码。
import 'package:flutter/material.dart';class RootPage extends StatefulWidget { @override _RootPageState createState() => new _RootPageState();}class _RootPageState extends State<RootPage> { FeedPage feedPage; Widget currentPage; @override void initState() { super.initState(); feedPage = FeedPage(this.callback); currentPage = feedPage; } void callback(Widget nextPage) { setState(() { this.currentPage = nextPage; }); } @override Widget build(BuildContext context) { return new Scaffold( //Current page to be changed from other classes too? body: currentPage ); }}class FeedPage extends StatefulWidget { Function callback; FeedPage(this.callback); @override _feedPageState createState() => new _feedPageState();}class _feedPageState extends State<FeedPage> { @override Widget build(BuildContext context) { return new FlatButton( onPressed: () { this.widget.callback(new NextPage());// setState(() {// //change the currentPage in RootPage so it switches FeedPage away and gets a new class that I'll make// }); }, child: new Text('Go to a new page but keep root, just replace this feed part'), ); }}
