导航到其他页面并返回后，Flutter Isolate 不会执行 setState

Question

您好，我有一个带有计数器的徽章，每当我启动我的 Android 警报管理器时，它应该增加计数器并实时更新 UI。我用隔离来做到这一点。一切正常，但是当我转到新的页面路由然后返回时，不再执行 SetState。我的错误在哪里？

  int _counter = 0;

  String isolateName = 'isolate';
  final ReceivePort port = ReceivePort();
  static SendPort uiSendPort;


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

    IsolateNameServer.registerPortWithName(
      port.sendPort,
      isolateName,
    );

    port.listen((_) async => await _incrementCounter());
  }

  Future<void> _incrementCounter() async {
    print('Increment counter!');

    // Ensure we've loaded the updated count from the background isolate.
    await prefs.reload();

    if (!mounted) return;
    setState(() {
      print("geht in die SetState");
      _counter++;
    });
  }

///
///This is in my Callback for my Android Alarm Manager...
          final prefs = await SharedPreferences.getInstance();
          int currentCount = prefs.getInt(countKey) ?? 0;
          await prefs.setInt(countKey, currentCount + 1);

          // This will be null if we're running in the background.
          uiSendPort ??= IsolateNameServer.lookupPortByName('isolate');
          uiSendPort?.send(null);

Answer 1

initState返回后不再调用，返回后尝试强制执行你想要的函数

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