Я использовал TabBar() в своем приложении для флаттера, и оно работало, пока я не обнаружил, что мой TabBarView() испортился при изменении размера экрана.После следующего этого вопроса, который я обнаружил, решение моей проблемы - Expanded() для TabBarView().Я старался изо всех сил, но все, что я получаю, - это большая ошибка при рендеринге моих данных.
⡿flutter: ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
flutter: The following assertion was thrown during performLayout():
flutter: RenderFlex children have non-zero flex but incoming height constraints are unbounded.
⣟flutter: When a column is in a parent that does not provide a finite height constraint, for example if it is
flutter: in a vertical scrollable, it will try to shrink-wrap its children along the vertical axis. Setting a
flutter: flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining
flutter: space in the vertical direction.
flutter: These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child
flutter: cannot simultaneously expand to fit its parent.
flutter: Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible
flutter: children (using Flexible rather than Expanded). This will allow the flexible children to size
flutter: themselves to less than the infinite remaining space they would otherwise be forced to take, and
flutter: then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum
flutter: constraints provided by the parent.
flutter: If this message did not help you determine the problem, consider using debugDumpRenderTree():
flutter: https://flutter.dev/debugging/#rendering-layer
flutter: http://docs.flutter.io/flutter/rendering/debugDumpRenderTree.html
flutter: The affected RenderFlex is:
flutter: RenderFlex#bc077 relayoutBoundary=up2 NEEDS-LAYOUT NEEDS-PAINT(creator: Column ← TabWidget ← Column ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ← CustomMultiChildLayout ← AnimatedBuilder ← DefaultTextStyle ← AnimatedDefaultTextStyle ← _InkFeatures-[GlobalKey#4f100 ink renderer] ← NotificationListener<LayoutChangedNotification> ← PhysicalModel ← ⋯, parentData: offset=Offset(0.0, 0.0); flex=null; fit=null (can use size), constraints: BoxConstraints(w=375.0, 0.0<=h<=Infinity), size: MISSING, direction: vertical, mainAxisAlignment: start, mainAxisSize: min, crossAxisAlignment: start, textDirection: ltr, verticalDirection: down)
flutter: The creator information is set to:
flutter: Column ← TabWidget ← Column ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ←
flutter: CustomMultiChildLayout ← AnimatedBuilder ← DefaultTextStyle ← AnimatedDefaultTextStyle ←
flutter: _InkFeatures-[GlobalKey#4f100 ink renderer] ← NotificationListener<LayoutChangedNotification> ←
flutter: PhysicalModel ← ⋯
flutter: The nearest ancestor providing an unbounded width constraint is: RenderFlex#0807f relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT:
flutter: creator: Column ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ← CustomMultiChildLayout ←
flutter: AnimatedBuilder ← DefaultTextStyle ← AnimatedDefaultTextStyle ← _InkFeatures-[GlobalKey#4f100 ink
flutter: renderer] ← NotificationListener<LayoutChangedNotification> ← PhysicalModel ←
flutter: AnimatedPhysicalModel ← Material ← ⋯
flutter: parentData: offset=Offset(0.0, 0.0); id=_ScaffoldSlot.body (can use size)
flutter: constraints: BoxConstraints(0.0<=w<=375.0, 0.0<=h<=591.0)
flutter: size: MISSING
flutter: direction: vertical
flutter: mainAxisAlignment: start
flutter: mainAxisSize: min
flutter: crossAxisAlignment: stretch
flutter: verticalDirection: down
flutter: See also: https://flutter.dev/layout/
flutter: If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
flutter: https://github.com/flutter/flutter/issues/new?template=BUG.md
flutter:
flutter: When the exception was thrown, this was the stack:
flutter: #0 RenderFlex.performLayout.<anonymous closure> (package:flutter/src/rendering/flex.dart:691:11)
flutter: #1 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:717:10)
flutter: #2 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #3 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:743:15)
flutter: #4 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #5 MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:142:11)
flutter: #6 _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:443:7)
flutter: #7 MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:212:7)
flutter: #8 RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:356:14)
flutter: #9 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #10 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #11 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #12 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #13 _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1214:11)
flutter: #14 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #15 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #16 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #17 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #18 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #19 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #20 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #21 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15)
flutter: #22 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #23 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #24 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #25 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #26 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #27 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #28 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #29 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #30 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #31 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #32 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #33 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #34 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:3067:13)
flutter: #35 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #36 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15)
flutter: #37 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #38 __RenderTheatre&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #39 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #40 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #41 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #42 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #43 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #44 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #45 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #46 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #47 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #48 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
flutter: #49 RenderObject.layout (package:flutter/src/rendering/object.dart:1620:7)
flutter: #50 RenderView.performLayout (package:flutter/src/rendering/view.dart:151:13)
flutter: #51 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1497:7)
flutter: #52 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:766:18)
flutter: #53 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:346:19)
flutter: #54 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:701:13)
flutter: #55 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:285:5)
flutter: #56 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1012:15)
flutter: #57 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:952:9)
flutter: #58 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:773:7)
flutter: #60 _Timer._runTimers (dart:isolate-patch/timer_impl.dart:382:19)
flutter: #61 _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:416:5)
flutter: #62 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:171:12)
flutter: (elided one frame from package dart:async-patch)
flutter:
flutter: The following RenderObject was being processed when the exception was fired: RenderFlex#bc077 relayoutBoundary=up2 NEEDS-LAYOUT NEEDS-PAINT:
flutter: creator: Column ← TabWidget ← Column ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ←
flutter: CustomMultiChildLayout ← AnimatedBuilder ← DefaultTextStyle ← AnimatedDefaultTextStyle ←
flutter: _InkFeatures-[GlobalKey#4f100 ink renderer] ← NotificationListener<LayoutChangedNotification> ←
flutter: PhysicalModel ← ⋯
⣯flutter: parentData: offset=Offset(0.0, 0.0); flex=null; fit=null (can use size)
flutter: constraints: BoxConstraints(w=375.0, 0.0<=h<=Infinity)
flutter: size: MISSING
flutter: direction: vertical
flutter: mainAxisAlignment: start
flutter: mainAxisSize: min
flutter: crossAxisAlignment: start
flutter: textDirection: ltr
flutter: verticalDirection: down
flutter: This This RenderObject had the following descendants (showing up to depth 5):
flutter: child 1: RenderPadding#ec776 relayoutBoundary=up3 NEEDS-PAINT
flutter: child: RenderDecoratedBox#82c7d relayoutBoundary=up4 NEEDS-PAINT
flutter: child: RenderPadding#47def relayoutBoundary=up5 NEEDS-PAINT
flutter: child: RenderCustomPaint#d3174 relayoutBoundary=up6 NEEDS-PAINT
flutter: child: _TabLabelBarRenderer#1dbbb relayoutBoundary=up7 NEEDS-PAINT
flutter: child 2: _RenderScrollSemantics#ab273 NEEDS-LAYOUT NEEDS-PAINT
flutter: child: RenderPointerListener#85f41 NEEDS-LAYOUT NEEDS-PAINT
flutter: child: RenderSemanticsGestureHandler#dfb17 NEEDS-LAYOUT NEEDS-PAINT
flutter: child: RenderPointerListener#36472 NEEDS-LAYOUT NEEDS-PAINT
flutter: child: RenderSemanticsAnnotations#0d0f0 NEEDS-LAYOUT NEEDS-PAINT
flutter: ════════════════════════════════════════════════════════════════════════════════════════════════════
flutter: Another exception was thrown: RenderBox was not laid out: RenderFlex#bc077 relayoutBoundary=up2 NEEDS-PAINT
flutter: Another exception was thrown: RenderBox was not laid out: RenderFlex#0807f relayoutBoundary=up1 NEEDS-PAINT
flutter: Another exception was thrown: NoSuchMethodError: The method '>' was called on null.
Теперь, чтобы дать вам представление о том, что я делал, у меня есть класс виджетов, в котором я определил свой TabBar, и я использую это в разных местах.
Это мой виджет для класса TabBar:
@override
Widget build(BuildContext context) {
return Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Container(
margin: EdgeInsets.only(left: 16.0, right: 16.0),
decoration: BoxDecoration(
color: Colors.white.withOpacity(0.0),
border: Border(bottom: BorderSide(color: Colors.grey, width: 0.5))),
child: TabBar(
unselectedLabelColor: Colors.grey,
unselectedLabelStyle: TextStyle().copyWith(fontSize: 16.0, fontWeight: FontWeight.normal),
labelColor: Color.fromRGBO(253, 92, 99, 1),
labelStyle: TextStyle().copyWith(fontSize: 16.0, fontWeight: FontWeight.bold),
indicatorColor: Color.fromRGBO(253, 92, 99, 1),
indicatorWeight: widget.indicatorWeight,
controller: _controller,
tabs: [
new Tab(
child: Padding(
padding: EdgeInsets.only(top: 18.0),
child: Text(widget.childOneHeader, style: TextStyle(fontSize: 15.0)),
)
),
new Tab(
child: Padding(
padding: EdgeInsets.only(top: 18.0),
child: Text(widget.childTwoHeader, style: TextStyle(fontSize: 15.0)),
)
),
new Tab(
child: Padding(
padding: EdgeInsets.only(top: 18.0),
child: Text(widget.childThreeHeader, style: TextStyle(fontSize: 15.0)),
)
)
]
)
),
Expanded(
//height: widget.layoutHeight,
child: new TabBarView(
controller: _controller,
children: <Widget>[
widget.childOne,
widget.childTwo,
widget.childThree
],
)
)
]
);
Данные с widget. поступают из его конструктора.
Теперь у меня естьЯ использовал это на моей странице, которая имеет ListView() для моего TabBarView() children, поэтому я передаю его только от них.
Класс, использующий код TabBar:
body: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Text('Heading'),
Container(),
TabWidget(
indicatorWeight: 1.0,
childOneHeader: 'Title 1',
childTwoHeader: 'Title 2',
childThreeHeader: 'Title 3',
childOne: ListView(
shrinkWrap: true,
scrollDirection: Axis.vertical,
children: this.isDataNull ?
[Container(
child: errorWidget,
)]
: this.getOffersWidgets()
),
childTwo: ListView(
shrinkWrap: true,
scrollDirection: Axis.vertical,
children: this.isDataNull ?
[Container(
child: errorWidget,
)]
: this.getBarWidgets()
),
childThree: ListView(
shrinkWrap: true,
scrollDirection: Axis.vertical,
children: this.isDataNull ?
[Container(
child: errorWidget,
)]
: this.getEventWidget()
)
)
]
);
Я старался изо всех сил, не мог заставить его работать.Все, что я получаю, это пустая страница, ничего больше.Пожалуйста, помогите мне с этим.Спасибо:)
РЕШЕНИЕ:
Поскольку я нашел выход, поэтому я думаю, что мои друзья, которые увидят этот вопрос в будущем, получат пользу от вопросатакже.
Это ссылка на ответ, кстати, если вы хотите взглянуть на это: Решение моей проблемы
В классе, использующем tabbarcode, обернитеTabWidget внутри Expanded() и отдых будет таким же, и ваша работа выполнена.
body: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Text('Heading'),
Container(),
Expanded(
child: TabWidget(//your content goes here)
)
Особая благодарность MFARKAN .
Обратите внимание, никогда не используйте Expanded () или Flexible () внутри ListView () или любого прокручиваемого виджета, потому что они требуют конечной высоты.используйте его внутри контента, но не для Expanded ()
Спасибо, ребята!:)