我有问题使用SingleChildScrollView在这种方式下，我不知道什么是错的，我不断得到这个错误。
如果添加SingleChildScrollView，页面将为空白（不会显示所有小部件），但如果删除SingleChildScrollView，页面将显示。
未配置RenderBox：渲染填充#583c0重新布局边界= up 1需要-油漆需要-合成-位-更新'软件包：flutter/src/rendering/box. dart'：失败的Assert：行1929位置12：'具有大小
相关的导致错误的小部件是支架支架：file：///Users/mac/Documents/Uneleap-Platform-master/lib/screens/Pages/forum/forum.dart：25：12
下面是代码
SafeArea(
minimum: EdgeInsets.only(left: 25.0, right: 20.0, top: 10.0),
child: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisSize: MainAxisSize.min,
children: [
WidgetForum(
details: 'The Get Is Not Geting together ?',
name: 'Nina Simon',
url: 'assets/dashboard_pic.png',
),
SizedBox(
height: 5,
),
WidgetForum(
details:
'''Notes is designed for whatever’s on your mind.\nJot down your thoughts. Download Notes.\nThere is something wonderful in writing. \nThe Get Is Not Getting Together?''',
name: 'James Nugar',
url: 'assets/dashboard_pic.png',
),
Text(
'Topics',
style: TextStyle(
fontSize: 35,
),
),
Expanded(
child: ListView.separated(
scrollDirection: Axis.horizontal,
separatorBuilder: (_, inedex) => SizedBox(
width: 20,
),
itemCount: topics.length,
itemBuilder: (context, index) {
return Container(
height: 50,
width: 100,
decoration: BoxDecoration(
color: Colors.red,
borderRadius: BorderRadius.circular(15),
image: DecorationImage(
image: AssetImage('assets/saved_2.png'),
fit: BoxFit.fill,
),
),
child: Column(
children: [
Padding(
padding: const EdgeInsets.all(8.0),
child: Align(
alignment: Alignment.bottomLeft,
child: Text(
topics[index].schoolNmae!,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold),
),
),
)
],
),
);
}),
),
WidgetForum(
details:
'''Notes is designed for whatever’s on your mind.\nJot down your thoughts. Download Notes.\nThere is something wonderful in writing. \nThe Get Is Not Getting Together?''',
name: 'Sam Ajayi',
url: 'assets/dashboard_pic.png',
),
],
),
),
),
// bottomSheet:
floatingActionButton: FloatingActionButton(
onPressed: () {
Scaffold.of(context).showBottomSheet<void>((BuildContext context) {
return Container(
height: 250,
decoration: BoxDecoration(
color: Colors.black,
borderRadius: BorderRadius.only(
topLeft: Radius.circular(10),
),
),
child: Padding(
padding: const EdgeInsets.symmetric(
vertical: 50,
horizontal: 15.0,
),
child: Column(
children: [
Row(
children: [
Icon(
CustomIcons.answers_forum,
color: Colors.grey,
),
SizedBox(
width: 10,
),
Text(
'Post',
style: TextStyle(
fontSize: 25,
fontWeight: FontWeight.bold,
color: Colors.white,
),
)
],
),
Padding(
padding: const EdgeInsets.only(right: 120.0),
child: Divider(
thickness: 2,
color: Colors.white,
),
),
Row(
children: [
Icon(
CustomIcons.create_forum,
color: Colors.grey,
),
SizedBox(
width: 10,
),
Text(
'Create Forum',
style: TextStyle(
fontSize: 25,
fontWeight: FontWeight.bold,
color: Colors.white,
),
)
],
),
Align(
alignment: Alignment.bottomRight,
child: GestureDetector(
onTap: () {
Navigator.pop(context);
},
child: Container(
height: 70,
width: 70,
decoration: BoxDecoration(
shape: BoxShape.circle,
color: Colors.white,
),
child: Center(
child: Icon(Icons.add),
),
),
),
)
],
),
),
);
});
},
child: Icon(Icons.add),
),
);
}
}
class WidgetForum extends StatefulWidget {
final String? name;
final String? details;
final String? url;
WidgetForum(
{Key? key, required this.name, required this.details, required this.url})
: super(key: key);
@override
_WidgetForumState createState() => _WidgetForumState();
}
class _WidgetForumState extends State<WidgetForum> {
@override
Widget build(BuildContext context) {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Row(
children: [
Container(
height: 50,
width: 50,
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage(widget.url!),
fit: BoxFit.fill,
),
),
),
SizedBox(
width: 5,
),
Text(
widget.name!,
style: TextStyle(fontWeight: FontWeight.bold, fontSize: 25),
)
],
),
PopupMenuButton(
color: Colors.black,
offset: Offset(0, 40),
itemBuilder: (_) => <PopupMenuItem<String>>[
new PopupMenuItem<String>(
child: Center(
child: Text(
'Fellow',
style: TextStyle(
color: Colors.white,
),
),
),
),
new PopupMenuItem<String>(
child: Center(
child: Text(
'Block',
style: TextStyle(
color: Colors.white,
),
),
),
),
new PopupMenuItem<String>(
child: Center(
child: Text(
'Report',
style: TextStyle(
color: Colors.white,
),
),
),
),
],
child: Container(
height: 20,
width: 20,
child: SvgPicture.asset('assets/library_pre.svg'),
),
),
],
),
SizedBox(height: 18),
Text(
widget.details!,
style: TextStyle(fontSize: 15),
),
SizedBox(height: 18),
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Row(
children: [
Icon(
CustomIcons.icons8_up_2_11,
color: Colors.red,
),
Text('36'),
Icon(
CustomIcons.icons8_down,
color: Colors.grey,
),
Icon(
CustomIcons.answers_forum,
color: Colors.grey,
),
Text('3')
],
),
Text('Sep 2, 2020')
],
),
Divider(
thickness: 1,
)
],
);
}
}
5条答案
按热度按时间xzv2uavs1#
如果
Column具有父SingleChildScrollView，则不能在Column中使用Expanded，因为当您使用列时，它会尝试位于屏幕高度内，而当在内部使用展开时，列会将剩余空间分配给展开小部件的子小部件，现在如果您使用SingleChildScrollView，它会尝试展开（按方向，在您的情况下为垂直方向）尽可能长的时间，但由于您使用的是Expanded，它试图占用剩余空间，因此它会无限扩展，从而引发错误，因此要么删除
SingleChildScrollView并使用Column和Expanded，要么删除Expanded并使用SingleChildScrollView，同时确保ListView中的ShrinkWrap为true。或者滚动所有小部件您可以使用
SingleChildScrollView在此处删除
Expanded小部件。rekjcdws2#
把它 Package 在一个容器里，并增加一个高度。为我修正了它。
jljoyd4f3#
我通过将
Column小部件包含在Container小部件中来解决这个问题，该小部件包含一组width和heightffscu2ro4#
如果列具有父SingleChildScrollView，则不能使用“在列中展开”，因为当您使用列时，它会尝试处于屏幕高度，而当在内部使用展开时，该列会将剩余空间分配给展开小部件的子小部件。现在，如果您使用SingleChildScrollView，它会尝试展开（按方向，在您的情况下为垂直方向）尽可能长的时间，但由于您使用的是Expanded，它试图占用剩余空间，因此它会无限扩展，从而引发错误，
因此要么删除SingleChildScrollView并使用Column和Expanded，要么删除Expanded并使用SingleChildScrollView也要确保在ListView中ShrinkWrap为true。
tquggr8v5#
我发现了同样的问题。但在我的例子中，我试图为listTile类的尾随属性提供一行小部件。我通过用容器 Package 该行并设置其宽度来解决它。