如何实现嵌套的ListView,或者说如何将ListView小部件嵌入可滚动的父级?
想象一下一个报告页面,其中某个部分是一份条目列表。
如何实现嵌套的ListView,或者说如何将ListView小部件嵌入可滚动的父级?
想象一下一个报告页面,其中某个部分是一份条目列表。
对于子ListView,请使用该参数:
shrinkWrap: true,
physics: ClampingScrollPhysics(),
对我而言,添加 physics: ClampingScrollPhysics()
和 shrinkWrap: true
有奏效。
示例代码:
@override
Widget build(BuildContext context) {
return Container(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Expanded(
child: ListView.builder(
shrinkWrap: true,
itemCount: 123,
itemBuilder: (BuildContext context, int index) {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text('Parent'),
ListView.builder(
itemCount: 2,
physics: ClampingScrollPhysics(),
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return Text('Child');
}),
],
);
}),
)
],
),
);
}
ListView
与主滚动视图独立滚动,则应使用NestedScrollView
。否则,请使用CustomScrollView
。NestedScrollView
方法的代码。
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(),
);
}
}
class MyHomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new Scaffold(
body: new NestedScrollView(
headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
return <Widget>[
new SliverAppBar(
pinned: true,
title: new Text('Flutter Demo'),
),
];
},
body: new Column(
children: <Widget>[
new FlutterLogo(size: 100.0, colors: Colors.purple),
new Container(
height: 300.0,
child: new ListView.builder(
itemCount: 60,
itemBuilder: (BuildContext context, int index) {
return new Text('Item $index');
},
),
),
new FlutterLogo(size: 100.0, colors: Colors.orange),
],
),
),
);
}
}
截图:
代码:
var _container = Container(
height: 200,
color: Colors.blue,
margin: EdgeInsets.symmetric(vertical: 10),
);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text("ListView")),
body: Padding(
padding: const EdgeInsets.all(40.0),
child: ListView( // parent ListView
children: <Widget>[
_container,
_container,
Container(
height: 200, // give it a fixed height constraint
color: Colors.teal,
// child ListView
child: ListView.builder(itemBuilder: (_, i) => ListTile(title: Text("Item ${i}"))),
),
_container,
_container,
_container,
],
),
),
);
}
对于内部的Listview,我只需添加以下代码,就解决了我的问题。
shrinkWrap: true,
physics: ScrollPhysics(),
感谢Serdar Polat的贡献:
ListView.builder( // outer ListView
itemCount: 4,
itemBuilder: (_, index) {
return Column(
children: [
Container(
color: Colors.blue,
alignment: Alignment.center,
child: Text('Header $index'),
),
ListView.builder( // inner ListView
shrinkWrap: true, // 1st add
physics: ClampingScrollPhysics(), // 2nd add
itemCount: 10,
itemBuilder: (_, index) => ListTile(title: Text('Item $index')),
)
],
);
},
)
使用shrinkWrap来包装您的内容,使用ClampingScrollPhysics来使用父级滚动。
ListView.builder(
shrinkWrap: true,
physics: const ClampingScrollPhysics(),
itemCount: yourList.length,
itemBuilder: (context, index) => YourWidget(items[index]),
),
我使用这个:
scrollController.addListener(onScroll);
void onScroll(){
if(scrollController.offset == 0.0
|| scrollController.position.extentBefore == 0.0
|| scrollController.position.extentAfter == 0.0){
scrollPhysics = NeverScrollableScrollPhysics();
Future.delayed(Duration(seconds: 1), (){
scrollPhysics = ClampingScrollPhysics();
setState((){});
});
setState((){});;
}
}
Expanded(
child: ListView.builder(
shrinkWrap: true,
padding: const EdgeInsets.all(8),
itemCount: requestList.length,
itemBuilder: (BuildContext context, int index) {
int que = index;
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Container(
padding: const EdgeInsets.only(
left: 20,
top: 10,
bottom: 10,
right: 20),
child: Text(
'${que++} . ${requestList[index].question}',
textAlign: TextAlign.center,
style: TextStyle(
fontSize: 14,
color: HexColor(HexColor.black),
fontFamily: 'montserrat_regular',
decoration: TextDecoration.none,
),
)),
ListView.builder(
itemCount: requestList[index].questionOptions!.length,
physics: ClampingScrollPhysics(),
shrinkWrap: true,
itemBuilder: (BuildContext context, int subindex) {
return Row(
children: <Widget>[
Radio(
value: 1,
groupValue: radio_value[index],
onChanged: (values) async {
setState(() {
radio_value[index] = 1;
qutionCheckModel[index].response =
"yes";
});
}),
Container(
child: Text(
requestList[index].questionOptions![subindex],
textAlign: TextAlign.center,
style: TextStyle(
fontSize: 14,
color: HexColor(HexColor.black),
fontFamily: 'montserrat_regular',
decoration: TextDecoration.none,
),
),
),
],
);
}),
],
);
}),
),
ScrollBar
中,而ScrollBar
又嵌套在ScrollConfiguration
中,最后再嵌套在一个Container
中时,此方法对我无效。 - Kaki Master Of Time