以画红框的为例，这明显是Row里面套TextField：
class ListItem2 extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Container(
padding: EdgeInsets.fromLTRB(ScreenUtil().setWidth(30), 0, ScreenUtil().setWidth(30), 0),
height: ScreenUtil().setHeight(88),
width: ScreenUtil().setWidth(750),
alignment: Alignment.center,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(width: 1, color:Colors.black12)
)
),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
'需求面积',
style:TextStyle(
fontSize: ScreenUtil().setSp(30)
),
),
Row(
children: <Widget>[
TextField(
keyboardType: TextInputType.number,
maxLines: 1,
decoration: InputDecoration(
hintText: '请输入需求面积',
border: InputBorder.none
),
),
Text(
'方',
style:TextStyle(
fontSize: ScreenUtil().setSp(28),
color: Color(0xFF666666),
)
)
],
),
],
),
);
}
}
但是，一运行就报了下面的错误：I/flutter ( 3346): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter ( 3346): The following assertion was thrown during performLayout():
I/flutter ( 3346): An InputDecorator, which is typically created by a TextField, cannot have an unbounded width.
I/flutter ( 3346): This happens when the parent widget does not provide a finite width constraint. For example, if the
I/flutter ( 3346): InputDecorator is contained by a Row, then its width must be constrained. An Expanded widget or a
I/flutter ( 3346): SizedBox can be used to constrain the width of the InputDecorator or the TextField that contains it.
I/flutter ( 3346): 'package:flutter/src/material/input_decorator.dart':
I/flutter ( 3346): Failed assertion: line 910 pos 7: 'layoutConstraints.maxWidth < double.infinity'
I/flutter ( 3346): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter ( 3346): more information in this error message to help you determine and fix the underlying cause.
I/flutter ( 3346): In either case, please report this assertion by filing a bug on GitHub:
I/flutter ( 3346): https://github.com/flutter/flutter/issues/new?template=BUG.md
I/flutter ( 3346): Widget creation tracking is currently disabled. Enabling it enables improved error messages. It can
I/flutter ( 3346): be enabled by passing `--track-widget-creation` to `flutter run` or `flutter test`.
I/flutter ( 3346): When the exception was thrown, this was the stack:
I/flutter ( 3346): #2 _RenderDecoration._layout (package:flutter/src/material/input_decorator.dart:910:7)
I/flutter ( 3346): #3 _RenderDecoration.performLayout (package:flutter/src/material/input_decorator.dart:1214:44)
I/flutter ( 3346): #4 RenderObject.layout (package:flutter/src/rendering/object.dart:1701:7)
报错太长，就不都放上来了。
百度了好久没找到，再google找到了，说是在textFidle外面套个Expanded，即改造如下：
class ListItem2 extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Container(
padding: EdgeInsets.fromLTRB(ScreenUtil().setWidth(30), 0, ScreenUtil().setWidth(30), 0),
height: ScreenUtil().setHeight(88),
width: ScreenUtil().setWidth(750),
alignment: Alignment.center,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(width: 1, color:Colors.black12)
)
),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
'需求面积',
style:TextStyle(
fontSize: ScreenUtil().setSp(30)
),
),
Row(
children: <Widget>[
//在这里套了个Expanded
Expanded(
child: TextField(
keyboardType: TextInputType.number, //数字键盘
maxLines: 1,
decoration: InputDecoration(
hintText: '请输入需求面积',
border: InputBorder.none
),
),
),
Text(
'方',
style:TextStyle(
fontSize: ScreenUtil().setSp(28),
color: Color(0xFF666666),
)
)
],
),
],
),
);
}
}
一运行，还是报相同的错误。以为这种方法不行，找了半天，还没找到。死马当活马医，就把TextField外层的Row也给套上，因为这个Row外面还有个Row，代码如下：
class ListItem2 extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Container(
padding: EdgeInsets.fromLTRB(ScreenUtil().setWidth(30), 0, ScreenUtil().setWidth(30), 0),
height: ScreenUtil().setHeight(88),
width: ScreenUtil().setWidth(750),
alignment: Alignment.center,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(width: 1, color:Colors.black12)
)
),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
'需求面积',
style:TextStyle(
fontSize: ScreenUtil().setSp(30)
),
),
//在这里也套了个Expanded
Expanded(
child: Row(
children: <Widget>[
//在这里套了个Expanded
Expanded(
child: TextField(
keyboardType: TextInputType.number, //数字键盘
maxLines: 1,
decoration: InputDecoration(
hintText: '请输入需求面积',
border: InputBorder.none
),
),
),
Text(
'方',
style:TextStyle(
fontSize: ScreenUtil().setSp(28),
color: Color(0xFF666666),
)
)
],
),
)
],
),
);
}
}
再次运行，发现效果出来了，这个问题困扰了我一个多小时，在这里记下，免得下次再犯。