を使用すると、私は1つの行に2つの構成のウィジェットを配置する必要があります。Flutterレイアウト：Flutter内のFlex（または別のRow）内にRowを配置するにはどうすればよいですか？また、スタックウィジェット
注：構成ウィジェットは国境内の各及び2つのテキストとTextFormField （もちろん、私は二回、それを必要とする 「boxText」と命名されました
Stack
Image and others
Form
Row or Flex or Whatever:
+------------------------------+ +------------------------------+
| Text Text TextFormField | | Text Text TextFormField |
+------------------------------+ +------------------------------+
私のコード（涙）：両方のようなさまざまなデータを）持っています 重要：例外はTextFormFieldが追加されている場合にのみ発生します。
@Override ウィジェットのビルド（BuildContextコンテキスト）{可能な場合は、これを置くことができる方法、
// Composed Widget
Widget boxText = new Container(
decoration: new BoxDecoration(
border: new Border.all(
color: Colors.cyan[100],
width: 3.0,
style: BorderStyle.solid,
),
),
margin: new EdgeInsets.all(5.0),
padding: new EdgeInsets.all(8.0),
child: new Row(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
new Text(
'Text',
style: null,
),
new Text(
'Text',
style: null,
),
new TextFormField(
decoration: const InputDecoration(
hintText: '',
labelText: 'label',
),
obscureText: true,
),
],
),
);
return new Scaffold(
key: _scaffoldKey,
body: new Stack(
alignment: AlignmentDirectional.topStart,
textDirection: TextDirection.ltr,
fit: StackFit.loose,
overflow: Overflow.clip,
children: <Widget>[
new Container(
color: Colors.red[200],
margin: new EdgeInsets.only(
left: MediaQuery.of(context).size.width * 0.05,
right: MediaQuery.of(context).size.width * 0.05,
top: MediaQuery.of(context).size.height * 0.4,
bottom: MediaQuery.of(context).size.height * 0.1,
),
width: MediaQuery.of(context).size.width,
height: MediaQuery.of(context).size.height,
child: new Form(
key: _formKey,
child: new ListView(
padding: const EdgeInsets.symmetric(horizontal: 16.0),
children: <Widget>[
new Flex(
direction: Axis.horizontal,
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
boxText,
boxText,
],
),
],
),
),
),
],
),
);
}
が
══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════ The following assertion was thrown during performLayout(): RenderFlex children have non-zero flex but incoming width constraints are unbounded. When a row is in a parent that does not provide a finite width constraint, for example if it is in a horizontal scrollable, it will try to shrink-wrap its children along the horizontal axis. Setting a flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining space in the horizontal direction. These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child cannot simultaneously expand to fit its parent. Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible children (using Flexible rather than Expanded). This will allow the flexible children to size themselves to less than the infinite remaining space they would otherwise be forced to take, and then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum constraints provided by the parent. The affected RenderFlex is: RenderFlex#4db4f relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT The creator information is set to: Row ← Padding ← DecoratedBox ← Padding ← Container ← Flex ← RepaintBoundary-[<0>] ← NotificationListener ← KeepAlive ← AutomaticKeepAlive ← SliverList ← SliverPadding ← ⋯ The nearest ancestor providing an unbounded width constraint is: RenderFlex#31897 relayoutBoundary=up4 NEEDS-LAYOUT NEEDS-PAINT creator: Flex ← RepaintBoundary-[<0>] ← NotificationListener ← KeepAlive ← AutomaticKeepAlive ← SliverList ← SliverPadding ← Viewport ← _ScrollableScope ← IgnorePointer-[GlobalKey#d9a15] ← Listener ← _GestureSemantics ← ⋯ parentData: (can use size) constraints: BoxConstraints(w=889.6, 0.0<=h<=Infinity) size: MISSING direction: horizontal mainAxisAlignment: start mainAxisSize: max crossAxisAlignment: center textDirection: ltr verticalDirection: downSee also: https://flutter.io/layout/ If this message did not help you determine the problem, consider using debugDumpRenderTree(): https://flutter.io/debugging/#rendering-layer http://docs.flutter.io/flutter/rendering/debugDumpRenderTree.html If none of the above helps enough to fix this problem, please don't hesitate to file a bug: https://github.com/flutter/flutter/issues/new When the exception was thrown, this was the stack: #0
RenderFlex.performLayout. (package:flutter/src/rendering/flex.dart:690:11) #1
RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:711:10) #2
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #3 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11) #4
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #5
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #6
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #7 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11) #8
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #9 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:737:15) #10
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #11
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #12
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #13 RenderSliverList.performLayout (package:flutter/src/rendering/sliver_list.dart:164:27) #14
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #15 RenderSliverPadding.performLayout (package:flutter/src/rendering/sliver_padding.dart:182:11) #16
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #17 RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:286:13) #18
RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:979:12) #19
RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:903:20) #20
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #21
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #22
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #23
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #24
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #25
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #26
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #27
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #28
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #29 RenderConstrainedBox.performLayout (package:flutter/src/rendering/proxy_box.dart:257:13) #30
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #31 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11) #32
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #33 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:466:15) #34
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #35 MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:124:11) #36
_ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:91:7) #37
MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:194:7) #38
RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:338:14) #39
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #40
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #41
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #42
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #43
_RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1005:24) #44
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #45
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #46
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #47 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:466:15) #48
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #49
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #50
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #51
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #52
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #53
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #54
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #55
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #56
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #57
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #58
RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2749:26) #59
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #60
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #61
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #62 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:466:15) #63
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #64
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #65
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #66
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #67
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #68
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #69
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #70
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #71
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #72
RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13) #73
RenderObject.layout (package:flutter/src/rendering/object.dart:1969:7) #74 RenderView.performLayout (package:flutter/src/rendering/view.dart:142:13) #75
RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1844:7) #76
PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1133:18) #77
BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:262:19) #78
BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:581:22) #79
BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:200:5) #80
BindingBase&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:713:15) #81
BindingBase&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:649:9) #82
BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding.scheduleWarmUpFrame. (package:flutter/src/rendering/binding.dart:286:20) #84
_Timer._runTimers (dart:isolate-patch/dart:isolate/timer_impl.dart:367) #85
_Timer._handleMessage (dart:isolate-patch/dart:isolate/timer_impl.dart:401) #86
_RawReceivePortImpl._handleMessage (dart:isolate-patch/dart:isolate/isolate_patch.dart:163) The following RenderObject was being processed when the exception was fired: RenderFlex#4db4f relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT creator: Row ← Padding ← DecoratedBox ← Padding ← Container ← Flex ← RepaintBoundary-[<0>] ← NotificationListener ← KeepAlive ← AutomaticKeepAlive ← SliverList ← SliverPadding ← ⋯ parentData: offset=Offset(0.0, 0.0) (can use size) constraints: BoxConstraints(unconstrained) size: MISSING direction: horizontal mainAxisAlignment: start mainAxisSize: max crossAxisAlignment: start textDirection: ltr verticalDirection: down This RenderObject had the following descendants (showing up to depth 5): RenderParagraph#ef986 NEEDS-LAYOUT NEEDS-PAINT RenderConstrainedBox#4a834 NEEDS-LAYOUT NEEDS-PAINT RenderSemanticsGestureHandler#272e2 NEEDS-LAYOUT NEEDS-PAINT RenderPointerListener#38266 NEEDS-LAYOUT NEEDS-PAINT RenderConstrainedBox#5ca9f NEEDS-LAYOUT NEEDS-PAINT RenderStack#7c271 NEEDS-LAYOUT NEEDS-PAINT RenderTransform#bf3b4 NEEDS-LAYOUT NEEDS-PAINT RenderOpacity#98951 NEEDS-LAYOUT NEEDS-PAINT RenderPadding#78af4 NEEDS-LAYOUT NEEDS-PAINT ════════════════════════════════════════════════════════════════════════════════════════════════════ Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true. Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true. Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true. Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true. Another exception was thrown: 'package:flutter/src/rendering/sliver_multi_box_adaptor.dart': Failed assertion: line 458 pos 12: 'child.hasSize': is not true. Another exception was thrown: NoSuchMethodError: The getter 'scrollExtent' was called on null. Another exception was thrown: NoSuchMethodError: The method 'debugAssertIsValid' was called on null. Another exception was thrown: NoSuchMethodError: The getter 'visible' was called on null. Another exception was thrown: NoSuchMethodError: The getter 'paintExtent' was called on null.
ありがとうLIBRARYレンダリングでキャッチ 例外なく動作するウィジェット。
