Flutter: setState() or markNeedsBuild() called when widget tree was locked... during orientation change
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Updated on December 05, 2022Comments
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Admin over 1 year
I want to create a App whose UI can be updated based on device orientation. In Portait layout, i use a drawer to show some elements (Fig.). In Landscape layout, there is no drawer but the elements are showed in a column at left of screen (Fig.). The program works, when the drawer is closed.
But when i switch orientation from portait to landscape with drawer opened, i got error of "setState() or markNeedsBuild() called when widget tree was locked" The stack provides this info:
Built build\app\outputs\apk\debug\app-debug.apk. I/FlutterActivityDelegate(28527): onResume setting current activity to this I/flutter (28527): PORTRAIT LAYOUT!!!!!!!!!!!!!!!!!!!!!! I/hwaps (28527): JNI_OnLoad I/flutter (28527): LANDSCAPE LAYOUT!!!!!!!!!!!!!!!!!!!!!! I/flutter (28527): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════ I/flutter (28527): The following assertion was thrown while finalizing the widget tree: I/flutter (28527): setState() or markNeedsBuild() called when widget tree was locked. I/flutter (28527): This _ModalScope<dynamic> widget cannot be marked as needing to build because the framework is I/flutter (28527): locked. I/flutter (28527): The widget on which setState() or markNeedsBuild() was called was: I/flutter (28527): _ModalScope<dynamic>-[LabeledGlobalKey<_ModalScopeState<dynamic>>#e1f0f](state: I/flutter (28527): _ModalScopeState<dynamic>#830e3) I/flutter (28527): I/flutter (28527): When the exception was thrown, this was the stack: I/flutter (28527): #0 Element.markNeedsBuild.<anonymous closure> (package:flutter/src/widgets/framework.dart:3453:9) I/flutter (28527): #1 Element.markNeedsBuild (package:flutter/src/widgets/framework.dart:3462:6) I/flutter (28527): #2 State.setState (package:flutter/src/widgets/framework.dart:1141:14) I/flutter (28527): #3 _ModalScopeState._routeSetState (package:flutter/src/widgets/routes.dart:464:5) I/flutter (28527): #4 ModalRoute.setState (package:flutter/src/widgets/routes.dart:562:30) I/flutter (28527): #5 ModalRoute.changedInternalState (package:flutter/src/widgets/routes.dart:1018:5) I/flutter (28527): #6 _ModalRoute&TransitionRoute&LocalHistoryRoute.removeLocalHistoryEntry (package:flutter/src/widgets/routes.dart:348:7) I/flutter (28527): #7 LocalHistoryEntry.remove (package:flutter/src/widgets/routes.dart:296:12) I/flutter (28527): #8 DrawerControllerState.dispose (package:flutter/src/material/drawer.dart:201:20) I/flutter (28527): #9 StatefulElement.unmount (package:flutter/src/widgets/framework.dart:3821:12) I/flutter (28527): #10 _InactiveElements._unmount (package:flutter/src/widgets/framework.dart:1697:13) I/flutter (28527): #11 _InactiveElements._unmount.<anonymous closure> (package:flutter/src/widgets/framework.dart:1695:7) I/flutter (28527): #12 ComponentElement.visitChildren (package:flutter/src/widgets/framework.dart:3676:14) I/flutter (28527): #13 _InactiveElements._unmount (package:flutter/src/widgets/framework.dart:1693:13) I/flutter (28527): #14 _InactiveElements._unmount.<anonymous closure> (package:flutter/src/widgets/framework.dart:1695:7) I/flutter (28527): #15 ComponentElement.visitChildren (package:flutter/src/widgets/framework.dart:3676:14) I/flutter (28527): #16 _InactiveElements._unmount (package:flutter/src/widgets/framework.dart:1693:13) I/flutter (28527): #17 ListIterable.forEach (dart:_internal/iterable.dart:39:13) I/flutter (28527): #18 _InactiveElements._unmountAll (package:flutter/src/widgets/framework.dart:1706:25) I/flutter (28527): #19 BuildOwner.finalizeTree.<anonymous closure> (package:flutter/src/widgets/framework.dart:2328:27) I/flutter (28527): #20 BuildOwner.lockState (package:flutter/src/widgets/framework.dart:2160:15) I/flutter (28527): #21 BuildOwner.finalizeTree (package:flutter/src/widgets/framework.dart:2327:7) I/flutter (28527): #22 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:628:18) I/flutter (28527): #23 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:208:5) I/flutter (28527): #24 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15) I/flutter (28527): #25 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9) I/flutter (28527): #26 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:842:5) I/flutter (28527): #27 _invoke (dart:ui/hooks.dart:120:13) I/flutter (28527): #28 _drawFrame (dart:ui/hooks.dart:109:3) I/flutter (28527): ════════════════════════════════════════════════════════════════════════════════════════════════════ I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true. I/flutter (28527): Another exception was thrown: 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3424 pos 12: '_debugLifecycleState != _ElementLifecycle.defunct': is not true.
And i got a go back button at leading of Appbar(Fig.).
Here is my code:
import 'package:flutter/material.dart'; void main() => runApp(new MyApp()); class MyApp extends StatefulWidget { @override _MyAppState createState() => _MyAppState(); } class _MyAppState extends State<MyApp> { @override Widget build(BuildContext context) { return new MaterialApp( title: 'demo', theme: new ThemeData(primarySwatch: Colors.blue), home: new Home(), ); } } class Home extends StatefulWidget { @override _HomeState createState() => _HomeState(); } class _HomeState extends State<Home> { static const int SCREEN_WIDTH_MIN = 600; @override Widget build(BuildContext context) { Widget _homelayout; var screenWidth = MediaQuery.of(context).size.width; var screenOrientation = MediaQuery.of(context).orientation; if ((screenWidth > SCREEN_WIDTH_MIN) && (screenOrientation == Orientation.landscape)) { print('LANDSCAPE LAYOUT!!!!!!!!!!!!!!!!!!!!!!'); //_homelayout = _buildLandscapeLayout(context); _homelayout = _buildLandscapeLayout(); } else { print('PORTRAIT LAYOUT!!!!!!!!!!!!!!!!!!!!!!'); _homelayout = _buildPortraitLayout(); } return _homelayout; } Widget _buildPortraitLayout() { return new Scaffold( appBar: new AppBar( title: new Text('demo'), ), drawer: new DeviceListDrawer(), body: new Center( child: new Text('body'), ), ); } } Widget _buildLandscapeLayout() { return new Scaffold( appBar: new AppBar( title: new Text('demo'), ), body: new Center( child: new Row( children: <Widget>[ new DeviceListDrawer(), new Text('body') ], ), ), ); } class DeviceListDrawer extends StatefulWidget { @override _DeviceListDrawerState createState() => _DeviceListDrawerState(); } class _DeviceListDrawerState extends State<DeviceListDrawer> { @override Widget build(BuildContext context) { return new Container( width: 200.0, color: Colors.white, child: Column( children: <Widget>[ new Container( width: 200.0, color: Colors.blue, padding: new EdgeInsets.only( top: MediaQuery.of(context).padding.top + 16.0, bottom: 16.0), child: new Text('demo '), ), new Expanded( child: new ListView( children: <Widget>[ new Text('item 1'), new Text('item 2'), new Text('item 3'), ], ), ), new RaisedButton( child: new Text('add item'), onPressed: () {}, ) ], ), ); } }
Could you please point out what is the problem? And how i can make a layout dynamique? Thanks for your help.