new ListView(
children: [
new SizedBox(
height: 100.0,
child: ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
new Text("hi"),
new Text("hi"),
new Text("hi"),
],
),
),
],
),
我使用了大小的盒子,似乎仍然有错误。
这是我的小部件树: SingleChildScrollView - &gt;专栏 - &gt;儿童
Performing hot reload... flutter: ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════ flutter: The following assertion was thrown during performResize(): flutter: Vertical viewport was given unbounded height. flutter: Viewports expand in the scrolling direction to fill their container.In this case, a vertical flutter: viewport was given an unlimited amount of vertical space in which to expand. This situation flutter: typically happens when a scrollable widget is nested inside another scrollable widget. flutter: If this widget is always nested in a scrollable widget there is no need to use a viewport because flutter: there will always be enough vertical space for the children. In this case, consider using a Column flutter: instead. Otherwise, consider using the "shrinkWrap" property (or a ShrinkWrappingViewport) to size flutter: the height of the viewport to the sum of the heights of its children. flutter: flutter: When the exception was thrown, this was the stack: flutter: #0 RenderViewport.performResize.<anonymous closure> (package:flutter/src/rendering/viewport.dart:944:15) flutter:
#1 RenderViewport.performResize (package:flutter/src/rendering/viewport.dart:997:6) flutter: #2 RenderObject.layout (package:flutter/src/rendering/object.dart:1555:9) flutter: #3
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #4 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #5
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #6 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #7
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #8 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #9
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #10 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #11
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #12 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #13 RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:738:15) flutter: #14 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #15 RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:199:11) flutter: #16 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #17 _RenderSingleChildViewport.performLayout (package:flutter/src/widgets/single_child_scroll_view.dart:479:13) flutter: #18 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #19
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #20 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #21
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #22 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #23
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #24 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #25
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #26 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #27
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #28 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #29 RenderPositionedBox.performLayout (package:flutter/src/rendering/shifted_box.dart:381:13) flutter: #30 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #31 MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:141:11) flutter: #32
_ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:399:7) flutter: #33 MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:211:7) flutter: #34 RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:355:14) flutter: #35 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #36
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #37 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #38
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #39
_RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1143:11) flutter: #40 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #41
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #42 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #43
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #44 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #45
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #46 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #47 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:520:15) flutter: #48 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #49
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #50 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #51
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #52 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #53
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #54 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #55
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #56 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #57
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #58 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #59
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #60 RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2809:13) flutter: #61 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #62 RenderStack.performLayout (package:flutter/src/rendering/stack.dart:520:15) flutter: #63 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #64
__RenderTheatre&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #65 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #66
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #67 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #68
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #69 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #70
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #71 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #72
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #73 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #74
_RenderProxyBox&RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:109:13) flutter: #75 RenderObject.layout (package:flutter/src/rendering/object.dart:1570:7) flutter: #76 RenderView.performLayout (package:flutter/src/rendering/view.dart:125:13) flutter: #77 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1445:7) flutter: #78 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:709:18) flutter: #79
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:270:19) flutter: #80
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:627:13) flutter: #81
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:208:5) flutter: #82
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15) flutter: #83
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9) flutter: #84
_WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:751:7) flutter:
#86 _Timer._runTimers (dart:isolate/runtime/libtimer_impl.dart:382:19) flutter: #87
_Timer._handleMessage (dart:isolate/runtime/libtimer_impl.dart:416:5) flutter: #88 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:165:12) flutter: (elided one frame from package dart:async) flutter: flutter: The following RenderObject was being processed when the exception was fired: flutter: RenderViewport#c5015 NEEDS-LAYOUT NEEDS-PAINT flutter: creator: Viewport ← _ScrollableScope ← IgnorePointer-[GlobalKey#58446] ← Semantics ← Listener ← flutter: _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#efcf9] ← flutter: _ExcludableScrollSemantics-[GlobalKey#1ff3b] ← Scrollable ← ListView ← Column ← Padding ← ⋯ flutter: parentData: <none> (can use size) flutter: constraints: BoxConstraints(0.0<=w<=335.0,
0.0<=h<=Infinity) flutter: size: MISSING flutter: axisDirection: down flutter: crossAxisDirection: right flutter: offset: ScrollPositionWithSingleContext#05c53(offset: 0.0, range: null..null, viewport: null, flutter: ScrollableState, AlwaysScrollableScrollPhysics -> BouncingScrollPhysics, IdleScrollActivity#31dab, flutter: ScrollDirection.idle) flutter: anchor: 0.0 flutter: This RenderObject had the following descendants (showing up to depth 5): flutter: RenderSliverPadding#912f7 NEEDS-LAYOUT NEEDS-PAINT flutter: RenderSliverList#41182 NEEDS-LAYOUT NEEDS-PAINT flutter: RenderRepaintBoundary#8a6de NEEDS-LAYOUT NEEDS-PAINT flutter: RenderConstrainedBox#4bfc3 NEEDS-LAYOUT NEEDS-PAINT flutter:
_RenderExcludableScrollSemantics#0976e NEEDS-LAYOUT NEEDS-PAINT flutter: ════════════════════════════════════════════════════════════════════════════════════════════════════ flutter: Another exception was thrown: RenderBox was not laid out: RenderViewport#c5015 NEEDS-LAYOUT NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderViewport#c5015 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderIgnorePointer#a987c relayoutBoundary=up14 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderSemanticsAnnotations#9bd09 relayoutBoundary=up13 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderPointerListener#12af7 relayoutBoundary=up12 NEEDS-PAINT Reloaded 1 of 493 libraries in 603ms. flutter: Another exception was thrown: RenderBox was not laid out: RenderSemanticsGestureHandler#27e1a relayoutBoundary=up11 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out:
_RenderExcludableScrollSemantics#85fc5 relayoutBoundary=up10 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderFlex#19bee relayoutBoundary=up9 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderPadding#e802a relayoutBoundary=up8 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out:
_RenderSingleChildViewport#5d1aa relayoutBoundary=up7 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderIgnorePointer#f73b8 relayoutBoundary=up6 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderSemanticsAnnotations#610b2 relayoutBoundary=up5 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderPointerListener#cbdf9 relayoutBoundary=up4 NEEDS-PAINT flutter: Another exception was thrown: RenderBox was not laid out: RenderSemanticsGestureHandler#37577 relayoutBoundary=up3 NEEDS-PAINT flutter: Another exception was thrown: 'package:flutter/src/rendering/shifted_box.dart': Failed assertion: line 310 pos 12: 'child.hasSize': is not true. flutter: Another exception was thrown: RenderBox was not laid out:
_RenderSingleChildViewport#5d1aa relayoutBoundary=up7 NEEDS-P
医生摘要(查看所有详细信息,运行flutter doctor -v):
[✓] Flutter(Channel beta,v0.4.4,Mac OS X 10.13.1 17B1003,locale en-HK)
[✓] Android工具链 - 针对Android设备开发(Android SDK 26.0.2)
[✓] iOS工具链 - 为iOS设备开发(Xcode 9.2)
[✓] Android Studio(3.1版)
[✓]连接设备(3个可用)
答案 0 :(得分:9)
尝试此代码,
您可以使用以下代码在flutter中实现可滚动的行
对于可滚动列,只需将“行”更改为“列”
new SingleChildScrollView(
scrollDirection: Axis.horizontal,
child: new Row(
children: <Widget>[
new Text('hi'),
new Text('hi'),
new Text('hi'),
]
)
)
答案 1 :(得分:7)
您可以使用扩展窗口小部件来包装listView
。
展开的小部件会告诉屏幕以允许其占用的空间为准。
或者您也可以在shrinkWrap:true
小部件中编写ListView
(在很多情况下可以使用)。
答案 2 :(得分:5)
水平ListView
将垂直展开以占据其父级的高度。恰好在这种情况下,父亲是一个垂直ListView
,它具有无限高度。您需要约束内部ListView
的高度。
可能最简单的方法是通过SizedBox
小部件。
ListView(
children: [
SizedBox(
height: 300.0,
child: ListView(scrollDirection: Axis.horizontal, ...),
),
],
)
问题实际上是由垂直ListView
引起的,因为它是Column
的孩子。原因与上面类似,ListView
将扩展为其父级的高度,Column
具有无限高度。
此代码段显示症状。
Column(
children: <Widget>[
ListView(children: [Text("hi"), Text("hi"), Text("hi")]),
],
)
这种情况下的解决方案取决于您的设置。你可以再次将它包裹在SizedBox
附近。您可以将列项目作为ListView
的一部分。或者您也可以更改ListView
的{{1}}。
答案 3 :(得分:1)
包装&#39; ListView&#39;使用&#39; Expanded&#39;窗口小部件。
new Expanded (
child: new ListView (
.....
)
)
答案 4 :(得分:1)
原因是您不能在列表视图中使用列表视图,因此您必须根据要求将其中一个添加到列或行中。
new Listview(
children: <Widget>[
new SizedBox(
height:100.0,
child: new Row(
children: <Widget>[
new Text("hi"),
new Text("hi"),
new Text("hi"),
]
)
)
]
)
根据我的要求,这将满足您的要求。
答案 5 :(得分:1)
尝试设置ListView的以下属性
shrinkWrap: true,
physics: ClampingScrollPhysics(),
对我来说,大多数“未绑定”约束和滚动错误已解决。
答案 6 :(得分:0)
您需要将水平ListView
包装在SizedBox
小部件内。看看以下示例代码:
new SizedBox(
height: 72.0,
child: new ListView(
padding: const EdgeInsets.symmetric(vertical: 4.0),
children: listViewItems,
scrollDirection: Axis.horizontal,
),
),
答案 7 :(得分:0)
这似乎是一个懒惰的答案,但是您是否尝试过进行$ flutter clean
?
当我使用打开新的flutter项目时给定的标准样板运行此代码时,它运行得很好,并使用了给您带来问题的相同代码。
我知道这是一个比较老的问题,但希望有人会觉得有用。
这就是我使用的;
import 'package:flutter/material.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
@override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text(widget.title),
),
body:
_listView(),
);
}
ListView _listView() {
return new ListView(
children: [
new SizedBox(
height: 100.0,
child: ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
new Text("hi"),
new Text("hi"),
new Text("hi"),
],
),
),
],
);
}
}
这就是我得到的;
答案 8 :(得分:0)
使用此
child: SingleChildScrollView(
scrollDirection: Axis.horizontal,
child: Row(
children: <Widget>[
buildCard(context),
buildCard(context),
buildCard(context),
],
),
),
答案 9 :(得分:0)
所以您也可以这样做:
Container(
height: 100.0,
child: ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
new Text("hi"),
new Text("hi"),
new Text("hi"),
]
),
),
通过将ListView
包装在Container
小部件中
答案 10 :(得分:0)
您也可以尝试水平滚动和垂直滚动。
return Scaffold(
body: ListView.builder(
scrollDirection: Axis.vertical,
itemBuilder: (BuildContext context, int index) {
return Container(
height: 200,
margin: EdgeInsets.all(20),
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: 20,
itemBuilder: (BuildContext context, int index) {
return Container(
color: Colors.grey,
width: 100,
height: 100,
margin: EdgeInsets.all(20),
);
},
),
);
},
),
);