如何在卡片小部件中颤抖地解决“ RenderBox未布局:”
我有一张有三个容器的卡。前两个包含文本,最后一个包含文本旁边的TextFormField。所以我有一行人将两者保持在一起。唯一的事情是,当我添加TextFormField小部件时,它没有出现并且控制台抛出错误
══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (14101): The following assertion was thrown during
performLayout():
I/flutter (14101): BoxConstraints forces an infinite width.
I/flutter (14101): These invalid constraints were provided to
RenderRepaintBoundary's layout() function by the
I/flutter (14101): following function, which probably computed the invalid
constraints in question:
I/flutter (14101): _RenderDecoration._layout.layoutLineBox
(package:flutter/src/material/input_decorator.dart:750:11)
I/flutter (14101): The offending constraints were:
I/flutter (14101): BoxConstraints(w=Infinity, 0.0<=h<=100.0)
I/flutter (14101): Another exception was thrown: RenderBox was not laid out:
RenderPadding#150b0 relayoutBoundary=up3 NEEDS-PAINT
I/flutter (14101): Another exception was thrown:
'package:flutter/src/rendering/shifted_box.dart': Failed assertion: line 310
pos 12: 'child.hasSize': is not true.
I/flutter (14101): Another exception was thrown: RenderBox was not laid out:
RenderPhysicalShape#1d998 relayoutBoundary=up4
代码看起来像
import 'package:flutter/material.dart'; class Home extends StatefulWidget {
@override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
@override
Widget build(BuildContext context) {
return Container(
child: Center(
child: Card(
elevation: 2.0,
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Container(
height: 100.0,
color: Colors.purple,
),
Container(
height: 200.0,
color: Colors.pink,
child: Column(
children: <Widget>[
new RichText(
textAlign: TextAlign.center,
text: TextSpan(
text: 'Some Text',
style: TextStyle(
color: Colors.grey[800],
fontWeight: FontWeight.bold,
fontSize: 17.0),
),
),
new RichText(
softWrap: true,
textAlign: TextAlign.center,
text: TextSpan(
text:
'Some other text',
style: TextStyle(
color: Colors.black54,
fontWeight: FontWeight.normal,
fontSize: 17.0),
),
),
Row(
children: <Widget>[
Text('adfa'),
Text('data'),
Form(
child: TextFormField(),
),
],
)
],
),
),
],
),
),
));
}
}
回答:
简短的答案是,直到孩子拥有尺寸,父母才有尺寸。
TextFormField
导致问题。它需要限制宽度。
将其包装成Expanded
小部件或Container
宽度,例如下面的示例。
Row( children: <Widget>[
Expanded(
child: TextFormField()
),
],
)
以上是 如何在卡片小部件中颤抖地解决“ RenderBox未布局:” 的全部内容, 来源链接: utcz.com/qa/435387.html