我有一个
ListView.builder
,它的右侧有一个下拉箭头,这样当点击它时,它会显示另一个 listView.builder
及其项目。第一个列表效果很好,因为它采用了其子项目的大小,但第二个列表上没有发生相同的体验。我已经尝试了所有解决方案,但它仍然不起作用,因为我收到错误。
代码
Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
SizedBox(
height: 30,
),
Text(
"SELECT A PACKAGE",
textAlign: TextAlign.start,
style: TextStyle(
fontSize: 12,
fontFamily: 'Lato',
color: textColor,
fontWeight: FontWeight.w700,
),
),
SizedBox(
height: 14,
),
!isDataLoaded?ShimmerListView():
Expanded(
child: ListView.builder(
shrinkWrap: true,
physics: NeverScrollableScrollPhysics(),
itemCount: bloc.packages.length,
itemBuilder: (context, index){
return Container(
margin: EdgeInsets.only(bottom: 5),
child: Card(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.
all(Radius.circular(12)),
side: BorderSide(color:
borderColor, width: 1)
),
child: Container(
padding: EdgeInsets.symmetric(horizontal: 16, vertical: 16),
child: Row(
mainAxisSize: MainAxisSize.min,
children: [
Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
bloc.packages[index].title,
textAlign: TextAlign.start,
style: TextStyle(
fontSize: 16,
fontFamily: 'Lato',
color: primaryColor,
fontWeight: FontWeight.w700,
),
),
SizedBox(
height: 14,
),
Text(
bloc.packages[index].desc,
textAlign: TextAlign.start,
style: TextStyle(
fontSize: 14,
fontFamily: 'Lato',
color: textColor,
fontWeight: FontWeight.w500,
),
),
bloc.packages[index].isTapped?
Container(
height: 300,
child: ListView.builder(
physics: NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemCount: bloc.packages[globalIndex].plans.length,
itemBuilder: (context, index){
return Container(
width: 230,
margin: EdgeInsets.only(top: 14),
padding: EdgeInsets.symmetric
(horizontal: 10, vertical: 10),
decoration: BoxDecoration(
color:containerBgColor,
borderRadius: BorderRadius
.all(Radius.circular(12))
),
child: Row(
mainAxisSize: MainAxisSize.min,
children: [
Container(
width:24,
height:24,
decoration: BoxDecoration(
color: Colors.white,
shape: BoxShape.circle,
),
),
SizedBox(
width: 16,
),
Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
bloc.packages[index].desc,
textAlign: TextAlign.start,
style: TextStyle(
fontSize: 14,
fontFamily: 'Lato',
color: textColor,
fontWeight: FontWeight.w500,
),
),
SizedBox(
height: 10,
),
Text(
'NGN ${12000}',
textAlign: TextAlign.start,
style: TextStyle(
fontSize: 16,
fontFamily: 'Lato',
color: normalText,
fontWeight: FontWeight.w700,
),
),
],
),
],
),
);
},
),
)
:Container(),
],
),
Spacer(),
IconButton(icon:
Icon(
!bloc.packages[index].isTapped?
Mdi.chevronDown:
Mdi.chevronUp,
color: textColor,
), onPressed:(){
setState(() {
globalIndex = index;
bloc.packages[index].isTapped
= !bloc.packages[index].isTapped;
});
})
],
),
),
),
);
},
),
),
],
),
错误
RenderBox was not laid out: RenderRepaintBoundary#87e06 relayoutBoundary=up27 NEEDS-PAINT
尝试用展开的方式包装第二个列表,并给出固定的高度,但出现相同的错误。
ListView
需要有限的高度,但你内心的ListView
有无限的高度。ListView
、Container
或任何具有定义高度的小部件包裹内部 SizedBox
。
示例
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('title'),
),
body: ListView.builder(
itemCount: 20,
itemBuilder: (BuildContext context, int index) {
if (index == 10) {
return Container(
height: 200, // finite height
child: ListView.builder(
itemCount: 20,
itemBuilder: (BuildContext context, int index) {
return Container(
height: 30,
color: Color.fromRGBO(10, 255, index * 10, 100),
child: Text(index.toString()),
);
},
),
);
}
return Container(
height: 36,
color: Color.fromRGBO(index * 10, 20, 100, 100),
child: Text(index.toString()),
);
},
),
);
}
如果您想要更简洁的方法,请查看 ,以及类似问题的这个答案。
'constraints.hasBoundedWidth': is not true.
错误
ListView
提供有限的宽度。你的
ListView
是一排,宽度无限。要修复此问题,请按如下方式编辑第 39 行中的行。
Row(
children: [
Expanded( // 1- Wrap the Column with an Expanded
child: Column(
// ...
),
),
// Spacer(), 2- Remove Spacer
IconButton(
// ...
),
],
)
return CustomScrollView(
slivers: [
SliverList(
delegate: SliverChildBuilderDelegate(
childCount: 5,
(BuildContext context, int index) {
return Column(
children: [
if (index == 0) ...[Text('PART ONE')],
if (index < 4) ...[
ListTile(
title: Text('Part one $index'),
),
],
if (index == 4) ...[
Text('PART TWO'),
ListView.builder(
shrinkWrap: true,
itemCount: 3,
itemBuilder: (context, index) {
return ListTile(
title:
Text(' Part two ${index.toString()}'),
);
}),
],
],
);
},
),
),
],
);