Flutter - AutomaticKeepAliveClientMixin页面保持

页面切换后，页面保持；为了避免initState方法重复调用

三步操作：

1. 添加AutomaticKeepAliveClientMixin

class _ChatPageState extends State with AutomaticKeepAliveClientMixin 

2. wantKeepAlive

@override
// TODO: implement wantKeepAlive
bool get wantKeepAlive => true;

3. super.build

@override
Widget build(BuildContext context) {
  //第三步：添加super.build
  super.build(context);

  return Scaffold();
}

完整代码

class ChatPage extends StatefulWidget {
  const ChatPage({Key? key}) : super(key: key);

  @override
  State createState() => _ChatPageState();
}

//
class _ChatPageState extends State with AutomaticKeepAliveClientMixin {
  //第二步：wantKeepAlive
  @override
  // TODO: implement wantKeepAlive
  bool get wantKeepAlive => true;

  @override
  Widget build(BuildContext context) {
    //第三步：添加super.build
    super.build(context);

    return Scaffold();
  }
}