Flutter:如何将 Header 行添加到 ListView
Flutter : How to add a Header Row to a ListView
Flutter 的新手。我已经能够利用 HTTP 请求数据、构建 ListView
、编辑该列表中的行和其他基础知识。环境极佳。
我已经设法拼凑出一个结构糟糕的 Header 来实现 ListView
,但我知道这是不对的。我无法让 Header 文本正确排列。
我看到 Drawer
Class 有一个 DrawerHeader
Class,但是看不到 ListView
有一个 ListViewHeader
.
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Contacts'),
actions: <Widget>[
IconButton(icon: Icon(Icons.add_circle),
onPressed: getCustData
),
],
),
//body:
body: Column(
children: <Widget>[
Row(
children: <Widget>[
Expanded(child: Text('', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('First Name', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('Last Name', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('City', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('Customer Id', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
]
),
Expanded(child:Container(
child: ListView.builder(
itemCount: data == null ? 0 : data.length,
itemBuilder: (BuildContext context, int index) {
return InkWell(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => APIDetailView(data[index])),
);
},
child: ListTile( //return new ListTile(
onTap: null,
leading: CircleAvatar(
backgroundColor: Colors.blue,
child: Text(data[index]["FirstName"][0]),
),
title: Row(
children: <Widget>[
Expanded(child: Text(data[index]["FirstName"])),
Expanded(child: Text(data[index]["LastName"])),
Expanded(child: Text(data[index]["Bill_City"])),
Expanded(child: Text(data[index]["Customer_Id"])),
]
)
),
);
}, //itemBuilder
),
),
),
]
)
);
}
}
谢谢。
Return header 作为 itemBuilder 的第一行:
ListView.builder(
itemCount: data == null ? 1 : data.length + 1,
itemBuilder: (BuildContext context, int index) {
if (index == 0) {
// return the header
return new Column(...);
}
index -= 1;
// return row
var row = data[index];
return new InkWell(... with row ...);
},
);
这是我解决这个问题的方法。感谢@najeira 让我思考其他解决方案。
在第一个 body 栏中,我为 Header 使用了与 ListTile
.
相同的布局
因为我的数据 ListTil
e,在这种情况下,包括一个 CircleAvatar
,所有水平间距都有点偏离......呈现 CircleAvatar
的 5 列。 .. 然后是 4 个均匀间隔的列。
所以...我在第一个bodyColumn
的基础上加了一个ListTile
,一个CircleAvatar
加上一个backgroundColor
的透明,然后是一个Row
我的 4 个标题。
ListTile(
onTap: null,
leading: CircleAvatar(
backgroundColor: Colors.transparent,
),
title: Row(
children: <Widget>[
Expanded(child: Text("First Name")),
Expanded(child: Text("Last Name")),
Expanded(child: Text("City")),
Expanded(child: Text("Id")),
]
),
),
您可以像这样向项目列表中的第一项添加一列
new ListView.builder(
itemCount: litems.length,
itemBuilder: (BuildContext ctxt, int index) {
if (index == 0) {
return Column(
children: <Widget>[
Header(),
rowContent(index),
],
);
} else {
return rowContent(index);
}
},
)
您可以在 Column
中添加 Container
和 ListView
。
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
@override
void initState() {
// TODO: implement initState
super.initState();
}
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
appBar: AppBar(
title: Text("Demo App1"),
),
body: Column(
children: <Widget>[
Container(
height: 40.0,
child: Row(
children: <Widget>[
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Name",
style: TextStyle(fontSize: 18),
)),
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Age",
style: TextStyle(fontSize: 18),
)),
],
),
),
Expanded(
child: ListView.builder(
itemCount: 100,
itemBuilder: (BuildContext context, int index) {
return Row(
children: <Widget>[
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Name $index",
style: TextStyle(fontSize: 18),
)),
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Age $index",
style: TextStyle(fontSize: 18),
),
)
],
);
},
),
),
],
),
),
);
}
}
我创建了 listview_utils
包来减少构建页眉和页脚列表项所需的样板代码。这是使用包的示例代码:
import 'package:listview_utils/listview_utils.dart';
CustomListView(
header: Container(
child: Text('Header'),
),
itemCount: items.length,
itemBuilder: (BuildContext context, int index, _) {
return ListTile(
title: Text(item['title']),
);
},
);
我正在维护这个包。
najeira 的解决方案简单易行,但您可以在不触及索引的情况下获得相同且更灵活的结果。
您可以使用 CustomScrollView & SliverList 而不是使用 listView,它在功能上与 listView 相同。
return Scaffold(
body: CustomScrollView(
slivers: <Widget>[
SliverToBoxAdapter(
// you could add any widget
child: ListTile(
leading: CircleAvatar(
backgroundColor: Colors.transparent,
),
title: Row(
children: <Widget>[
Expanded(child: Text("First Name")),
Expanded(child: Text("Last Name")),
Expanded(child: Text("City")),
Expanded(child: Text("Id")),
],
),
),
),
SliverList(
delegate: SliverChildBuilderDelegate(
(context, index) {
return InkWell(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => APIDetailView(data[index])),
);
},
child: ListTile(
//return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.blue,
child: Text(data[index]["FirstName"][0]),
),
title: Row(
children: <Widget>[
Expanded(child: Text(data[index]["FirstName"])),
Expanded(child: Text(data[index]["LastName"])),
Expanded(child: Text(data[index]["Bill_City"])),
Expanded(child: Text(data[index]["Customer_Id"])),
],
),
),
);
},
childCount: data == null ? 0 : data.length,
),
),
],
),
);
在此代码示例中,我们正在处理如何在列表视图中添加第 header 行。
class HeaderRowListView extends StatelessWidget {
final List<int> _listData = List<int>.generate(100, (i) => i);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('ListView Header Row'),
),
body: ListView(
padding: EdgeInsets.all(8.0),
children: _listData.map((i) {
return i % 10 == 0
? Container(
color: Colors.grey.withOpacity(.5),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
mainAxisSize: MainAxisSize.max,
children: <Widget>[
Text("Header",
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
)),
Text("Feb 26th, 2019",
style: TextStyle(
fontSize: 14.0,
color: Colors.black45,
)),
],
),
padding: EdgeInsets.all(10.0),
)
: ListTile(
title: Text("Item $i"),
);
}).toList(),
),
);
}
}
看来您真正要找的是 DataTable 小部件而不是 ListView。
它具有可自定义的 Header,包括排序选项。
阅读文档,包括关于 api.flutter.dev 的一些很好的示例:Data Table CLass
使用 DataTable 小部件!
该小部件允许您构建 table。 代码: DataTable(columns: [], rows: [],)
示例:
DataTable(
columns: [
DataColumn(label: Text('Lang.')),
DataColumn(label: Text('Year')),
],
rows: [
DataRow(cells: [DataCell(Text('Dart')), DataCell(Text('2010'))]),
DataRow(cells: [DataCell(Text('Go')), DataCell(Text('2009'))]),
DataRow(cells: [DataCell(Text('PHP')), DataCell(Text('1994'))]),
DataRow(cells: [DataCell(Text('Java')), DataCell(Text('1995'))]),
],
)
输出:
您可以了解更多 DataTable by watching this official video or by visiting flutter.dev
我用这个:
body: Column(
children: [
Container(
// The header will be here
),
Expanded(
// The ListView
child: ListView.builder(
itemCount: // The length,
itemBuilder: (_, index) {
return //List Item Widget Here
}),
),
],
)
正在根据您的 api 数据寻找动态部分 headers。将此 class 添加到您的项目中。
class _FlutterSectionListViewState extends State<FlutterSectionListView> {
/// List of total number of rows and section in each group
var itemList = [];
int itemCount = 0;
int sectionCount = 0;
@override
void initState() {
/// ----#4
sectionCount = widget.numberOfSection();
/// ----#5
itemCount = listItemCount();
super.initState();
}
/// ----#6
@override
Widget build(BuildContext context) {
return ListView.builder(
itemCount: itemCount,
itemBuilder: (context, index) {
return buildItemWidget(index);
},
key: widget.key,
);
}
/// Get the total count of items in list(including both row and sections)
int listItemCount() {
itemList = [];
int rowCount = 0;
for (int i = 0; i < sectionCount; i++) {
/// Get the number of rows in each section using callback
int rows = widget.numberOfRowsInSection(i);
/// Here 1 is added for each section in one group
rowCount += rows + 1;
itemList.insert(i, rowCount);
}
return rowCount;
}
/// ----#7
/// Get the widget for each item in list
Widget buildItemWidget(int index) {
/// ----#8
IndexPath indexPath = sectionModel(index);
/// ----#9
/// If the row number is -1 of any indexPath it will represent a section else row
if (indexPath.row < 0) {
/// ----#10
return widget.sectionWidget != null
? widget.sectionWidget!(indexPath.section)
: SizedBox(
height: 0,
);
} else {
return widget.rowWidget!(indexPath.section, indexPath.row);
}
}
/// Calculate/Map the indexPath for an item Index
IndexPath sectionModel(int index) {
int? row = 0;
int section = 0;
for (int i = 0; i < sectionCount; i++) {
int item = itemList[i];
if (index < item) {
row = (index - (i > 0 ? itemList[i - 1] : 0) - 1) as int?;
section = i;
break;
}
}
return IndexPath(section: section, row: row!);
}
}
/// Helper class for indexPath of each item in list
class IndexPath {
IndexPath({required this.section, required this.row});
int section = 0;
int row = 0;
}
根据您的 api 数据创建列表
List<List<Operator>> ops = [];
List<String> sections = [];
if(c.operatorStatuses.value!.availableOperators.length>0){
ops.add(c.operatorStatuses.value!.availableOperators);
sections.add("Müsait Operatörler");
}
if(c.operatorStatuses.value!.busyOperators.length>0){
ops.add(c.operatorStatuses.value!.busyOperators);
sections.add("Meşgul Operatörler");
}
if(c.operatorStatuses.value!.breakOperators.length>0){
ops.add(c.operatorStatuses.value!.breakOperators);
sections.add("Moladaki Operatörler");
}
if(c.operatorStatuses.value!.closedOperators.length>0){
ops.add(c.operatorStatuses.value!.closedOperators);
sections.add("Kapalı Operatörler");
}
显示在ui;
FlutterSectionListView(
numberOfSection: () => ops.length,
numberOfRowsInSection: (section) {
return ops[section].length;
},
sectionWidget: (section) {
if(section<ops.length){
return Container(
child: Padding(
padding: const EdgeInsets.all(8),
child: Text(sections[section]),
),
color: Colors.grey,
);
}else{
return SizedBox();
}
},
rowWidget: (section, row) {
if(row < ops[section].length){
Operator? op = ops[section][row];
return card(op);
}else{
return SizedBox();
}
},
)
感谢[这篇文章][1]。
注意:根据更新的数据,代码块有时会产生错误。
[1]: https://medium.com/@dharmendra_yadav/ios-like-sectioned-listview-widget-in-flutter-7cf9dab2dd1a
Flutter 的新手。我已经能够利用 HTTP 请求数据、构建 ListView
、编辑该列表中的行和其他基础知识。环境极佳。
我已经设法拼凑出一个结构糟糕的 Header 来实现 ListView
,但我知道这是不对的。我无法让 Header 文本正确排列。
我看到 Drawer
Class 有一个 DrawerHeader
Class,但是看不到 ListView
有一个 ListViewHeader
.
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Contacts'),
actions: <Widget>[
IconButton(icon: Icon(Icons.add_circle),
onPressed: getCustData
),
],
),
//body:
body: Column(
children: <Widget>[
Row(
children: <Widget>[
Expanded(child: Text('', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('First Name', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('Last Name', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('City', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('Customer Id', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
Expanded(child: Text('', style: TextStyle(height: 3.0, fontSize: 15.2, fontWeight: FontWeight.bold,))),
]
),
Expanded(child:Container(
child: ListView.builder(
itemCount: data == null ? 0 : data.length,
itemBuilder: (BuildContext context, int index) {
return InkWell(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => APIDetailView(data[index])),
);
},
child: ListTile( //return new ListTile(
onTap: null,
leading: CircleAvatar(
backgroundColor: Colors.blue,
child: Text(data[index]["FirstName"][0]),
),
title: Row(
children: <Widget>[
Expanded(child: Text(data[index]["FirstName"])),
Expanded(child: Text(data[index]["LastName"])),
Expanded(child: Text(data[index]["Bill_City"])),
Expanded(child: Text(data[index]["Customer_Id"])),
]
)
),
);
}, //itemBuilder
),
),
),
]
)
);
}
}
谢谢。
Return header 作为 itemBuilder 的第一行:
ListView.builder(
itemCount: data == null ? 1 : data.length + 1,
itemBuilder: (BuildContext context, int index) {
if (index == 0) {
// return the header
return new Column(...);
}
index -= 1;
// return row
var row = data[index];
return new InkWell(... with row ...);
},
);
这是我解决这个问题的方法。感谢@najeira 让我思考其他解决方案。
在第一个 body 栏中,我为 Header 使用了与 ListTile
.
因为我的数据 ListTil
e,在这种情况下,包括一个 CircleAvatar
,所有水平间距都有点偏离......呈现 CircleAvatar
的 5 列。 .. 然后是 4 个均匀间隔的列。
所以...我在第一个bodyColumn
的基础上加了一个ListTile
,一个CircleAvatar
加上一个backgroundColor
的透明,然后是一个Row
我的 4 个标题。
ListTile(
onTap: null,
leading: CircleAvatar(
backgroundColor: Colors.transparent,
),
title: Row(
children: <Widget>[
Expanded(child: Text("First Name")),
Expanded(child: Text("Last Name")),
Expanded(child: Text("City")),
Expanded(child: Text("Id")),
]
),
),
您可以像这样向项目列表中的第一项添加一列
new ListView.builder(
itemCount: litems.length,
itemBuilder: (BuildContext ctxt, int index) {
if (index == 0) {
return Column(
children: <Widget>[
Header(),
rowContent(index),
],
);
} else {
return rowContent(index);
}
},
)
您可以在 Column
中添加 Container
和 ListView
。
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
@override
void initState() {
// TODO: implement initState
super.initState();
}
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
appBar: AppBar(
title: Text("Demo App1"),
),
body: Column(
children: <Widget>[
Container(
height: 40.0,
child: Row(
children: <Widget>[
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Name",
style: TextStyle(fontSize: 18),
)),
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Age",
style: TextStyle(fontSize: 18),
)),
],
),
),
Expanded(
child: ListView.builder(
itemCount: 100,
itemBuilder: (BuildContext context, int index) {
return Row(
children: <Widget>[
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Name $index",
style: TextStyle(fontSize: 18),
)),
Container(
padding: EdgeInsets.all(4.0),
width: 100.0,
child: Text(
"Age $index",
style: TextStyle(fontSize: 18),
),
)
],
);
},
),
),
],
),
),
);
}
}
我创建了 listview_utils
包来减少构建页眉和页脚列表项所需的样板代码。这是使用包的示例代码:
import 'package:listview_utils/listview_utils.dart';
CustomListView(
header: Container(
child: Text('Header'),
),
itemCount: items.length,
itemBuilder: (BuildContext context, int index, _) {
return ListTile(
title: Text(item['title']),
);
},
);
我正在维护这个包。
najeira 的解决方案简单易行,但您可以在不触及索引的情况下获得相同且更灵活的结果。
您可以使用 CustomScrollView & SliverList 而不是使用 listView,它在功能上与 listView 相同。
return Scaffold(
body: CustomScrollView(
slivers: <Widget>[
SliverToBoxAdapter(
// you could add any widget
child: ListTile(
leading: CircleAvatar(
backgroundColor: Colors.transparent,
),
title: Row(
children: <Widget>[
Expanded(child: Text("First Name")),
Expanded(child: Text("Last Name")),
Expanded(child: Text("City")),
Expanded(child: Text("Id")),
],
),
),
),
SliverList(
delegate: SliverChildBuilderDelegate(
(context, index) {
return InkWell(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => APIDetailView(data[index])),
);
},
child: ListTile(
//return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.blue,
child: Text(data[index]["FirstName"][0]),
),
title: Row(
children: <Widget>[
Expanded(child: Text(data[index]["FirstName"])),
Expanded(child: Text(data[index]["LastName"])),
Expanded(child: Text(data[index]["Bill_City"])),
Expanded(child: Text(data[index]["Customer_Id"])),
],
),
),
);
},
childCount: data == null ? 0 : data.length,
),
),
],
),
);
在此代码示例中,我们正在处理如何在列表视图中添加第 header 行。
class HeaderRowListView extends StatelessWidget {
final List<int> _listData = List<int>.generate(100, (i) => i);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('ListView Header Row'),
),
body: ListView(
padding: EdgeInsets.all(8.0),
children: _listData.map((i) {
return i % 10 == 0
? Container(
color: Colors.grey.withOpacity(.5),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
mainAxisSize: MainAxisSize.max,
children: <Widget>[
Text("Header",
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
)),
Text("Feb 26th, 2019",
style: TextStyle(
fontSize: 14.0,
color: Colors.black45,
)),
],
),
padding: EdgeInsets.all(10.0),
)
: ListTile(
title: Text("Item $i"),
);
}).toList(),
),
);
}
}
看来您真正要找的是 DataTable 小部件而不是 ListView。 它具有可自定义的 Header,包括排序选项。
阅读文档,包括关于 api.flutter.dev 的一些很好的示例:Data Table CLass
使用 DataTable 小部件!
该小部件允许您构建 table。 代码: DataTable(columns: [], rows: [],)
示例:
DataTable(
columns: [
DataColumn(label: Text('Lang.')),
DataColumn(label: Text('Year')),
],
rows: [
DataRow(cells: [DataCell(Text('Dart')), DataCell(Text('2010'))]),
DataRow(cells: [DataCell(Text('Go')), DataCell(Text('2009'))]),
DataRow(cells: [DataCell(Text('PHP')), DataCell(Text('1994'))]),
DataRow(cells: [DataCell(Text('Java')), DataCell(Text('1995'))]),
],
)
输出:
您可以了解更多 DataTable by watching this official video or by visiting flutter.dev
我用这个:
body: Column(
children: [
Container(
// The header will be here
),
Expanded(
// The ListView
child: ListView.builder(
itemCount: // The length,
itemBuilder: (_, index) {
return //List Item Widget Here
}),
),
],
)
正在根据您的 api 数据寻找动态部分 headers。将此 class 添加到您的项目中。
class _FlutterSectionListViewState extends State<FlutterSectionListView> {
/// List of total number of rows and section in each group
var itemList = [];
int itemCount = 0;
int sectionCount = 0;
@override
void initState() {
/// ----#4
sectionCount = widget.numberOfSection();
/// ----#5
itemCount = listItemCount();
super.initState();
}
/// ----#6
@override
Widget build(BuildContext context) {
return ListView.builder(
itemCount: itemCount,
itemBuilder: (context, index) {
return buildItemWidget(index);
},
key: widget.key,
);
}
/// Get the total count of items in list(including both row and sections)
int listItemCount() {
itemList = [];
int rowCount = 0;
for (int i = 0; i < sectionCount; i++) {
/// Get the number of rows in each section using callback
int rows = widget.numberOfRowsInSection(i);
/// Here 1 is added for each section in one group
rowCount += rows + 1;
itemList.insert(i, rowCount);
}
return rowCount;
}
/// ----#7
/// Get the widget for each item in list
Widget buildItemWidget(int index) {
/// ----#8
IndexPath indexPath = sectionModel(index);
/// ----#9
/// If the row number is -1 of any indexPath it will represent a section else row
if (indexPath.row < 0) {
/// ----#10
return widget.sectionWidget != null
? widget.sectionWidget!(indexPath.section)
: SizedBox(
height: 0,
);
} else {
return widget.rowWidget!(indexPath.section, indexPath.row);
}
}
/// Calculate/Map the indexPath for an item Index
IndexPath sectionModel(int index) {
int? row = 0;
int section = 0;
for (int i = 0; i < sectionCount; i++) {
int item = itemList[i];
if (index < item) {
row = (index - (i > 0 ? itemList[i - 1] : 0) - 1) as int?;
section = i;
break;
}
}
return IndexPath(section: section, row: row!);
}
}
/// Helper class for indexPath of each item in list
class IndexPath {
IndexPath({required this.section, required this.row});
int section = 0;
int row = 0;
}
根据您的 api 数据创建列表
List<List<Operator>> ops = [];
List<String> sections = [];
if(c.operatorStatuses.value!.availableOperators.length>0){
ops.add(c.operatorStatuses.value!.availableOperators);
sections.add("Müsait Operatörler");
}
if(c.operatorStatuses.value!.busyOperators.length>0){
ops.add(c.operatorStatuses.value!.busyOperators);
sections.add("Meşgul Operatörler");
}
if(c.operatorStatuses.value!.breakOperators.length>0){
ops.add(c.operatorStatuses.value!.breakOperators);
sections.add("Moladaki Operatörler");
}
if(c.operatorStatuses.value!.closedOperators.length>0){
ops.add(c.operatorStatuses.value!.closedOperators);
sections.add("Kapalı Operatörler");
}
显示在ui;
FlutterSectionListView(
numberOfSection: () => ops.length,
numberOfRowsInSection: (section) {
return ops[section].length;
},
sectionWidget: (section) {
if(section<ops.length){
return Container(
child: Padding(
padding: const EdgeInsets.all(8),
child: Text(sections[section]),
),
color: Colors.grey,
);
}else{
return SizedBox();
}
},
rowWidget: (section, row) {
if(row < ops[section].length){
Operator? op = ops[section][row];
return card(op);
}else{
return SizedBox();
}
},
)
感谢[这篇文章][1]。
注意:根据更新的数据,代码块有时会产生错误。 [1]: https://medium.com/@dharmendra_yadav/ios-like-sectioned-listview-widget-in-flutter-7cf9dab2dd1a