我一直在尝试解决此问题，但是经过我的所有努力，我只得到了错误。经历了Align TextField with Dropdownbutton
的问题我曾尝试为TextField和DropDownButton制作不同的卡片，但同样遇到了同样的问题。
代码：
Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Container(
margin: EdgeInsets.only(top: 40.0, left: 16.0, right: 16.0),
child: Card(
color: Colors.white,
child: Row(
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
DropdownButtonHideUnderline(
child: DropdownButton(
value: _dropDownValue,
onChanged: (newValue){setState(() => _dropDownValue = newValue);},
items: _countryCode.map((value){
return DropdownMenuItem(
value: value,
child: Text(value)
);
}).toList()
)
),
Flexible(
child: TextEditorForPhoneNumber(this.phoneNum),
)
]
)
),
decoration: BoxDecoration(boxShadow: [
new BoxShadow(color: Color.fromRGBO(173, 179, 191, 0.3), blurRadius: 20.0, offset: new Offset(0, 12))
])
)
]
)
TextEditorForPhoneNumber
class TextEditorForPhoneNumber extends StatelessWidget {
final TextEditingController phoneNum;
TextEditorForPhoneNumber(this.phoneNum);
@override
Widget build(BuildContext context) {
return TextField(
autofocus: true,
cursorColor: Theme.of(context).primaryColor,
keyboardType: TextInputType.number,
controller: this.phoneNum,
decoration: InputDecoration(
hintText: 'Your Phone number'
)
);
}
}
错误：
flutter: ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
flutter: The following assertion was thrown during performLayout():
flutter: RenderIndexedStack object was given an infinite size during layout.
flutter: This probably means that it is a render object that tries to be as big as possible, but it was put
flutter: inside another render object that allows its children to pick their own size.
flutter: The nearest ancestor providing an unbounded width constraint is:
flutter: RenderFlex#c6ec2 relayoutBoundary=up9 NEEDS-LAYOUT NEEDS-PAINT
flutter: creator: Row ← DefaultTextStyle ← AnimatedDefaultTextStyle ← _InkFeatures-[GlobalKey#ed2b5 ink
flutter: renderer] ← NotificationListener<LayoutChangedNotification> ← CustomPaint ← _ShapeBorderPaint ←
flutter: PhysicalShape ← _MaterialInterior ← Material ← Padding ← Container ← ⋯
flutter: parentData: <none> (can use size)
flutter: constraints: BoxConstraints(w=335.0, 0.0<=h<=Infinity)
flutter: size: MISSING
flutter: direction: horizontal
flutter: mainAxisAlignment: start
flutter: mainAxisSize: max
flutter: crossAxisAlignment: center
flutter: textDirection: ltr
flutter: verticalDirection: down
flutter: The nearest ancestor providing an unbounded height constraint is:
flutter: RenderFlex#6f9ef relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT
flutter: creator: Column ← Builder ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ← CustomMultiChildLayout
flutter: ← AnimatedBuilder ← DefaultTextStyle ← AnimatedDefaultTextStyle ← _InkFeatures-[GlobalKey#29d80
flutter: ink renderer] ← NotificationListener<LayoutChangedNotification> ← PhysicalModel ←
flutter: AnimatedPhysicalModel ← ⋯
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: max
flutter: crossAxisAlignment: stretch
flutter: verticalDirection: down
flutter: The constraints that applied to the RenderIndexedStack were:
flutter: BoxConstraints(unconstrained)
flutter: The exact size it was given was:
flutter: Size(Infinity, Infinity)
flutter: See https://flutter.io/layout/ for more information.
flutter:
flutter: When the exception was thrown, this was the stack:
flutter: #0 RenderBox.debugAssertDoesMeetConstraints.<anonymous closure> (package:flutter/src/rendering/box.dart:1749:9)
flutter: #1 RenderBox.debugAssertDoesMeetConstraints (package:flutter/src/rendering/box.dart:1823:6)
flutter: #2 RenderBox.size=.<anonymous closure> (package:flutter/src/rendering/box.dart:1543:17)
flutter: #3 RenderBox.size= (package:flutter/src/rendering/box.dart:1543:65)
flutter: #4 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:480:7)
flutter: #5 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #6 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:738:15)
flutter: #7 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #8 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11)
flutter: #9 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #10 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #11 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #12 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #13 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #14 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #15 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #16 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:738:15)
flutter: #17 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #18 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #19 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #20 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #21 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #22 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #23 _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1188:11)
flutter: #24 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #25 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11)
flutter: #26 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #27 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #28 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #29 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #30 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #31 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11)
flutter: #32 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #33 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:738:15)
flutter: #34 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #35 MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:142:11)
flutter: #36 _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:339:7)
flutter: #37 MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:212:7)
flutter: #38 RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:356:14)
flutter: #39 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #40 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #41 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #42 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #43 _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1188:11)
flutter: #44 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #45 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #46 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #47 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #48 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #49 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #50 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #51 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15)
flutter: #52 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #53 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #54 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #55 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #56 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #57 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #58 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #59 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #60 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #61 _RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:104:13)
flutter: #62 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #63 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2879:14)
flutter: #64 RenderObject.layout (package:flutter/src/rendering/object.dart:1634:7)
flutter: #65 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:510:15)
flutter: #66 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1509:7)
flutter: #67 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:768:18)
flutter: #68 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:281:19)
flutter: #69 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:677:13)
flutter: #70 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&SemanticsBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:219:5)
flutter: #71 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15)
flutter: #72 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9)
flutter: #73 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:842:5)
flutter: #74 _invoke (dart:ui/hooks.dart:154:13)
flutter: #75 _drawFrame (dart:ui/hooks.dart:143:3)
flutter:
flutter: The following RenderObject was being processed when the exception was fired:
flutter: RenderIndexedStack#29331 relayoutBoundary=up15 NEEDS-LAYOUT NEEDS-PAINT
flutter: creator: IndexedStack ← Row ← Padding ← Container ← DefaultTextStyle ← Listener ←
flutter: _GestureSemantics ← RawGestureDetector ← GestureDetector ← Semantics ← DropdownButton<String> ←
flutter: DropdownButtonHideUnderline ← ⋯
flutter: parentData: offset=Offset(0.0, 0.0); flex=null; fit=null (can use size)
flutter: constraints: BoxConstraints(unconstrained)
flutter: size: Size(Infinity, Infinity)
flutter: alignment: AlignmentDirectional.centerStart
flutter: textDirection: ltr
flutter: fit: loose
flutter: overflow: clip
flutter: index: null
flutter: This RenderObject has no descendants.
flutter: ════════════════════════════════════════════════════════════════════════════════════════════════════
flutter: Another exception was thrown: RenderFlex object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPadding object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPointerListener object was given an infinite size during layout.
flutter: Another exception was thrown: RenderSemanticsGestureHandler object was given an infinite size during layout.
flutter: Another exception was thrown: RenderSemanticsAnnotations object was given an infinite size during layout.
flutter: Another exception was thrown: RenderFlex object was given an infinite size during layout.
flutter: Another exception was thrown: _RenderInkFeatures object was given an infinite size during layout.
flutter: Another exception was thrown: RenderCustomPaint object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPhysicalShape object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPadding object was given an infinite size during layout.
flutter: Another exception was thrown: RenderSemanticsAnnotations object was given an infinite size during layout.
flutter: Another exception was thrown: RenderDecoratedBox object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPadding object was given an infinite size during layout.
flutter: Another exception was thrown: RenderSemanticsAnnotations object was given an infinite size during layout.
flutter: Another exception was thrown: _RenderInkFeatures object was given an infinite size during layout.
flutter: Another exception was thrown: RenderCustomPaint object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPhysicalShape object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPadding object was given an infinite size during layout.
flutter: Another exception was thrown: RenderSemanticsAnnotations object was given an infinite size during layout.
flutter: Another exception was thrown: RenderDecoratedBox object was given an infinite size during layout.
flutter: Another exception was thrown: RenderPadding object was given an infinite size during layout.
flutter: Another exception was thrown: NoSuchMethodError: The method '<=' was called on null.
flutter: Another exception was thrown: A RenderFlex overflowed by Infinity pixels on the bottom.
flutter: Another exception was thrown: Unsupported operation: Infinity or NaN toInt
flutter: Another exception was thrown: 'package:flutter/src/rendering/object.dart': Failed assertion: line 1411 pos 14: '_debugSubtreeRelayoutRootAlreadyMarkedNeedsLayout()': is not true.
flutter: Another exception was thrown: 'package:flutter/src/rendering/object.dart': Failed assertion: line 1411 pos 14: '_debugSubtreeRelayoutRootAlreadyMarkedNeedsLayout()': is not true.
扑扑医生
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel unknown, v1.0.0, on Mac OS X 10.14.5 18F132, locale en-US)
[✓] Android toolchain - develop for Android devices (Android SDK 28.0.3)
[✓] iOS toolchain - develop for iOS devices (Xcode 10.3)
[✓] Android Studio (version 3.4)
✗ Flutter plugin not installed; this adds Flutter specific functionality.
✗ Dart plugin not installed; this adds Dart specific functionality.
[✓] Connected device (1 available)
• No issues found!
尝试过：将globalKey赋予Container()，但没有成功。
请帮助。谢谢
解决方案：
找到了解决方案，因此上面的代码就UI而言是正确的，不幸的是，当API数据时，Flutter没有给我选项来将数据集从null更改为DropDownButton（）项中的数据进来。我的_countryCode正在从API中获取价值，并在几秒钟内保持为空，由于这个原因，它没有得到更新并给了我空值。 因此请注意项目数据，它不能为空
有关此问题的更多信息，请访问以下答案：A RenderFlex overflowed by Infinity pixels on the right when using DropdownButton widget