Flutter设置横屏致Android页面重置问题及解决方案

我需要将指定页面的屏幕方向设置为DeviceOrientation.landscapeLeft，但设置后，屏幕方向改变、UI渲染完成后，Activity会立即重置，应用直接返回首页。无论build方法返回什么内容，都会发生跳转，且无任何报错信息。

我尝试在进入该页面之前修改屏幕方向，但无论在哪个页面设置，最终都会跳转回主页面。

补充：已找到可行解决方案 #

需修改AndroidManifest文件：

修改前 #

<activity
   android:name=".MainActivity"    
 android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"

修改后 #

<activity
   android:name=".MainActivity"
    android:configChanges="orientation|keyboardHidden"

该修改可阻止页面重置问题。

相关代码 #

横屏页面（ConsumptionExpandedScreen）状态类代码 #

class _ConsumptionExpandedScreenState extends State<ConsumptionExpandedScreen>
    with WidgetsBindingObserver {
@override
  void initState() {
    super.initState();

    WidgetsBinding.instance.addObserver(this);
    WidgetsFlutterBinding.ensureInitialized();
    // 锁定屏幕方向为左侧横屏
    _setLandscapeOrientation();
   
  }
  @override
  void dispose() {
    logger.d("In the dispose function of the expanded screen");
    // 离开页面时重置屏幕方向为竖屏
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitUp,
    ]);
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      _setLandscapeOrientation();
    }
  }

  void _setLandscapeOrientation() {
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeLeft,
    ]);
  }

  @override
  Widget build(BuildContext context) {

      double screenWidth = MediaQuery.of(context).size.width;
      double screenHeight = MediaQuery.of(context).size.height;
      logger.d(
          "Expanded consumption the current size(width : height) is $screenWidth : $screenHeight");
...

主页面（MainApp）状态类代码 #

class _MainAppState extends State<MainApp> with WidgetsBindingObserver {

  Locale myLocale = const Locale('en', 'US');

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    // 按需处理应用生命周期变化
  }

  @override
  void didChangeMetrics() {
    final newSize = WidgetsBinding.instance.window.physicalSize;
    logger.d("New size: ${newSize.width} : ${newSize.height}");
    // 按需处理屏幕方向变化
    setState(() {}); // 触发重建以调整布局
  }

  @override
  void initState() {
    super.initState();

    _loadData();
  }

  void _loadData() async {
    final prefs = await SharedPreferences.getInstance();
    indexLanguage = prefs.getInt(langIndexKey);

    // print("The number of the index $indexLanguage");
    if (indexLanguage != null) {}
    setState(() {});
  }

  @override
  void dispose() {
    // _adapterStateStateSubscription.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return ChangeNotifierProvider<ValueChangeProvider>(
      create: (context) => ValueChangeProvider(),
      child: Consumer<ValueChangeProvider>(
        builder: (context, valueChangeProvider, _) {
          logger.d("The main screen ");
          double screenWidth = MediaQuery.of(context).size.width;
          double screenHeight = MediaQuery.of(context).size.height;
          logger.d(
              "The current size(width : height) is $screenWidth : $screenHeight");
          updatePaddingValues(context);

          return PaddingConfig(
            sidePadding: globalPaddingSide,
            topPadding: paddingTop,
            topHeaderPadding: paddingHeaderTop,
            child: MaterialApp(
              color: AppColors.backgroundColor,
              navigatorObservers: [
                BluetoothAdapterStateObserver(valueChangeProvider),
                routeObserver
              ],
              localizationsDelegates: AppLocalizations.localizationsDelegates,
              supportedLocales: AppLocalizations.supportedLocales,
              locale: valueChangeProvider.currentLocale,
              theme: lightTheme,
              debugShowCheckedModeBanner: false,
              initialRoute: initialAppRoute,
              routes: AppRoutes.routes,
            ),
          );
        },
      ),
    );
  }
}

跳转页面时的日志 #

I/flutter (18518): [D]  Expanded consumption the current size(width : height) is 360.0 : 708.0
I/flutter (18518): [D]  The main screen 
I/flutter (18518): [D]  The current size(width : height) is 672.0 : 360.0
I/flutter (18518): [D]  In the pairing list screen 
I/flutter (18518): [D]  Expanded consumption the current size(width : height) is 672.0 : 360.0
I/flutter (18518): [D]  Going to the pairing list
I/flutter (18518): [D]  In the pairing list screen 
I/flutter (18518): [D]  Expanded consumption the current size(width : height) is 672.0 : 360.0
I/flutter (18518): [D]  The main screen 
I/flutter (18518): [D]  The current size(width : height) is 360.0 : 708.0
I/flutter (18518): [D]  In the pairing list screen 
I/flutter (18518): [D]  In the pairing list screen 
I/flutter (18518): [D]  Expanded consumption the current size(width : height) is 360.0 : 708.0
I/flutter (18518): [D]  Going to the pairing list
I/flutter (18518): [D]  In the pairing list screen 
I/flutter (18518): [D]  In the pairing list screen 

内容的提问来源于stack exchange，提问作者Dries Vandenbussche