未检测到键盘。MediaQuery.of(context).viewInsets.bottom始终返回0.0

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final bottomInset = MediaQuery.of(context).viewInsets.bottom;
    return Container(
      // ...
    );
  }
}

class MyWidget extends StatefulWidget {
  @override
  _MyWidgetState createState() => _MyWidgetState();
}

class _MyWidgetState extends State<MyWidget> with WidgetsBindingObserver {
  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      final bottomInset = MediaQuery.of(context).viewInsets.bottom;
      print('Bottom inset: $bottomInset');
    }
  }

  @override
  Widget build(BuildContext context) {
    return Container(
      // ...
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Keyboard Example'),
      ),
      body: SingleChildScrollView(
        child: Container(
          padding: EdgeInsets.only(bottom: MediaQuery.of(context).viewInsets.bottom),
          child: Column(
            children: <Widget>[
              // ...
            ],
          ),
        ),
      ),
      resizeToAvoidBottomInset: true,
    );
  }
}