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问Flutter initState()返回'_debugLifecycleState == _StateLifecycle.created'：不为真
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Stack Overflow用户

提问于 2020-12-07 10:48:58

回答 2查看 493关注 0票数 0

尝试调用initState()时，Flutter返回错误'_debugLifecycleState == _StateLifecycle.created': is not true.

这是我的initState()函数。我已经确保它不在这个站点上的另一个类似问题中提到的build()函数中。

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

    dataRead = false;

    todayTask.clear();
    tomorrowTask.clear();
    upcomingTask.clear();

    tasks().then((data) {
      setState(() {

        for (int i =0; i< data.length; i++){
          if (taskDay(DateTime.parse(data[i].datetime)) == 0) todayTask.add(data[i]);
          else if (taskDay(DateTime.parse(data[i].datetime)) == 1) tomorrowTask.add(data[i]);
          else upcomingTask.add(data[i]);
        }

        dataRead = true;

      });
    });

    _tabController = TabController(vsync: this, length: 3);
  }

首次运行initState()时未出现错误。它只有在我显式调用它时才会出现。

颤动运行的结果--详细

[ +166 ms] E/flutter (30434): [ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 1113 pos 12: '_debugLifecycleState ==
_StateLifecycle.created': is not true.
[   +2 ms] E/flutter (30434): #0      _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:40:39)
[   +1 ms] E/flutter (30434): #1      _AssertionError._throwNew (dart:core-patch/errors_patch.dart:36:5)
[   +1 ms] E/flutter (30434): #2      State.initState (package:flutter/src/widgets/framework.dart:1113:12)
[   +1 ms] E/flutter (30434): #3      _TodoBodyState.initState (package:dyry/todobody.dart:70:11)
[        ] E/flutter (30434): #4      _TodoBodyState.build.<anonymous closure>.<anonymous closure> (package:dyry/todobody.dart:162:75)
[        ] E/flutter (30434): #5      _AddTodoState.build.<anonymous closure> (package:dyry/addtodo.dart:321:36)
[        ] E/flutter (30434): <asynchronous suspension>
[        ] E/flutter (30434): #6      _AddTodoState.build.<anonymous closure> (package:dyry/addtodo.dart)
[        ] E/flutter (30434): #7      _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:953:19)
[        ] E/flutter (30434): #8      _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:1059:38)
[        ] E/flutter (30434): #9      GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
[        ] E/flutter (30434): #10     TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:522:11)
[        ] E/flutter (30434): #11     BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:282:5)
[   +1 ms] E/flutter (30434): #12     BaseTapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:254:7)
[   +1 ms] E/flutter (30434): #13     GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:156:27)
[   +1 ms] E/flutter (30434): #14     GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:222:20)
[   +2 ms] E/flutter (30434): #15     GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
[   +1 ms] E/flutter (30434): #16     GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
[   +1 ms] E/flutter (30434): #17     GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
[   +1 ms] E/flutter (30434): #18     GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
[   +1 ms] E/flutter (30434): #19     _rootRunUnary (dart:async/zone.dart:1206:13)
[   +1 ms] E/flutter (30434): #20     _CustomZone.runUnary (dart:async/zone.dart:1100:19)
[   +1 ms] E/flutter (30434): #21     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7)
[   +1 ms] E/flutter (30434): #22     _invoke1 (dart:ui/hooks.dart:281:10)
[   +1 ms] E/flutter (30434): #23     _dispatchPointerDataPacket (dart:ui/hooks.dart:190:5)
[   +2 ms] E/flutter (30434):
[  +92 ms] D/InputMethodManager(30434): HSIFW - flag : 0 Pid : 30434

flutter

dart

回答 2

Stack Overflow用户

回答已采纳

发布于 2021-03-27 16:16:39

您应该创建另一个函数并在initState中调用该函数，而不是使用FutureDelayed。我也有同样的问题，我只需要提取函数就可以解决这个问题。下面是我的代码：

    @override
  void initState() {
    setState(() {
      _isLoading = true;
    });
    getInitData();

    super.initState();
  }

  Future<void> getInitData() async {
    await Provider.of<PassCardList>(context, listen: false).getCard();
    setState(() {
      _isLoading = false;
    });
  }

票数 1

Stack Overflow用户

发布于 2020-12-07 10:58:13

我认为setState是在创建小部件之前使用的。我会推迟setState的发布。

    @override
      void initState() {
        super.initState();
    
        dataRead = false;
    
        todayTask.clear();
        tomorrowTask.clear();
        upcomingTask.clear();

       Future.delayed(const Duration(milliseconds: 200), () {
    
        tasks().then((data) {
          setState(() {
    
            for (int i =0; i< data.length; i++){
              if (taskDay(DateTime.parse(data[i].datetime)) == 0) todayTask.add(data[i]);
              else if (taskDay(DateTime.parse(data[i].datetime)) == 1) tomorrowTask.add(data[i]);
              else upcomingTask.add(data[i]);
            }
    
            dataRead = true;
    
          });
        });
});
    
        _tabController = TabController(vsync: this, length: 3);
      }