Flutter 颤振中的可扩展列表视图/动态树状视图
我需要一个嵌套的树状视图，其中遍历列表并基于父子关系构建节点。当点击一个节点时，它会展开并用缩进显示其子节点。如果列表很长并且有多个节点且子节点本身有多个子节点，则还可以更改selectedt node.的textstyle颜色和2d滚动。怎么用？请提供帮助。您可以复制粘贴运行下面的完整代码Flutter 颤振中的可扩展列表视图/动态树状视图,flutter,recursion,dart,dynamic,tree,Flutter,Recursion,Dart,Dynamic,Tree,我需要一个嵌套的树状视图，其中遍历列表并基于父子关系构建节点。当点击一个节点时，它会展开并用缩进显示其子节点。如果列表很长并且有多个节点且子节点本身有多个子节点，则还可以更改selectedt node.的textstyle颜色和2d滚动。怎么用？请提供帮助。您可以复制粘贴运行下面的完整代码 您可以使用软件包 它有一些您可以自定义的功能，您可以看到下面的工作演示 对于父子关系，您可以在完整代码中看到initState（） @override void initState() { _n
您可以使用软件包
它有一些您可以自定义的功能，您可以看到下面的工作演示
对于父子关系，您可以在完整代码中看到
initState（）@override
void initState() {
_nodes = [
Node(
label: 'documents',
key: 'docs',
expanded: docsOpen,
icon: NodeIcon(
codePoint:
docsOpen ? Icons.folder_open.codePoint : Icons.folder.codePoint,
color: "blue",
),
children: [
Node(
label: 'personal',
key: 'd3',
TreeView(
controller: _treeViewController,
allowParentSelect: _allowParentSelect,
supportParentDoubleTap: _supportParentDoubleTap,
onExpansionChanged: (key, expanded) =>
_expandNode(key, expanded),
onNodeTap: (key) {
debugPrint('Selected: $key');
setState(() {
_selectedNode = key;
_treeViewController =
_treeViewController.copyWith(selectedKey: key);
});
},
theme: _treeViewTheme,
)
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_treeview/tree_view.dart';
import 'dart:convert';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'TreeView Example',
home: MyHomePage(title: 'TreeView Example'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
String _selectedNode;
List<Node> _nodes;
TreeViewController _treeViewController;
bool docsOpen = true;
final Map<ExpanderPosition, Widget> expansionPositionOptions = const {
ExpanderPosition.start: Text('Start'),
ExpanderPosition.end: Text('End'),
};
final Map<ExpanderType, Widget> expansionTypeOptions = const {
ExpanderType.caret: Icon(
Icons.arrow_drop_down,
size: 28,
),
ExpanderType.arrow: Icon(Icons.arrow_downward),
ExpanderType.chevron: Icon(Icons.expand_more),
ExpanderType.plusMinus: Icon(Icons.add),
};
final Map<ExpanderModifier, Widget> expansionModifierOptions = const {
ExpanderModifier.none: ModContainer(ExpanderModifier.none),
ExpanderModifier.circleFilled: ModContainer(ExpanderModifier.circleFilled),
ExpanderModifier.circleOutlined:
ModContainer(ExpanderModifier.circleOutlined),
ExpanderModifier.squareFilled: ModContainer(ExpanderModifier.squareFilled),
ExpanderModifier.squareOutlined:
ModContainer(ExpanderModifier.squareOutlined),
};
ExpanderPosition _expanderPosition = ExpanderPosition.start;
ExpanderType _expanderType = ExpanderType.caret;
ExpanderModifier _expanderModifier = ExpanderModifier.none;
bool _allowParentSelect = false;
bool _supportParentDoubleTap = false;
@override
void initState() {
_nodes = [
Node(
label: 'documents',
key: 'docs',
expanded: docsOpen,
icon: NodeIcon(
codePoint:
docsOpen ? Icons.folder_open.codePoint : Icons.folder.codePoint,
color: "blue",
),
children: [
Node(
label: 'personal',
key: 'd3',
icon: NodeIcon.fromIconData(Icons.input),
children: [
Node(
label: 'Resume.docx',
key: 'pd1',
icon: NodeIcon.fromIconData(Icons.insert_drive_file)),
Node(
label: 'Cover Letter.docx',
key: 'pd2',
icon: NodeIcon.fromIconData(Icons.insert_drive_file)),
]),
Node(
label: 'Inspection.docx',
key: 'd1',
// icon: NodeIcon.fromIconData(Icons.insert_drive_file),
),
Node(
label: 'Invoice.docx',
key: 'd2',
icon: NodeIcon.fromIconData(Icons.insert_drive_file)),
],
),
Node(
label: 'MeetingReport.xls',
key: 'mrxls',
icon: NodeIcon.fromIconData(Icons.insert_drive_file)),
Node(
label: 'MeetingReport.pdf',
key: 'mrpdf',
icon: NodeIcon.fromIconData(Icons.insert_drive_file)),
Node(
label: 'Demo.zip',
key: 'demo',
icon: NodeIcon.fromIconData(Icons.archive)),
];
_treeViewController = TreeViewController(
children: _nodes,
selectedKey: _selectedNode,
);
super.initState();
}
ListTile _makeExpanderPosition() {
return ListTile(
title: Text('Expander Position'),
dense: true,
trailing: CupertinoSlidingSegmentedControl(
children: expansionPositionOptions,
groupValue: _expanderPosition,
onValueChanged: (ExpanderPosition newValue) {
setState(() {
_expanderPosition = newValue;
});
},
),
);
}
SwitchListTile _makeAllowParentSelect() {
return SwitchListTile.adaptive(
title: Text('Allow Parent Select'),
dense: true,
value: _allowParentSelect,
onChanged: (v) {
setState(() {
_allowParentSelect = v;
});
},
);
}
SwitchListTile _makeSupportParentDoubleTap() {
return SwitchListTile.adaptive(
title: Text('Support Parent Double Tap'),
dense: true,
value: _supportParentDoubleTap,
onChanged: (v) {
setState(() {
_supportParentDoubleTap = v;
});
},
);
}
ListTile _makeExpanderType() {
return ListTile(
title: Text('Expander Style'),
dense: true,
trailing: CupertinoSlidingSegmentedControl(
children: expansionTypeOptions,
groupValue: _expanderType,
onValueChanged: (ExpanderType newValue) {
setState(() {
_expanderType = newValue;
});
},
),
);
}
ListTile _makeExpanderModifier() {
return ListTile(
title: Text('Expander Modifier'),
dense: true,
trailing: CupertinoSlidingSegmentedControl(
children: expansionModifierOptions,
groupValue: _expanderModifier,
onValueChanged: (ExpanderModifier newValue) {
setState(() {
_expanderModifier = newValue;
});
},
),
);
}
@override
Widget build(BuildContext context) {
TreeViewTheme _treeViewTheme = TreeViewTheme(
expanderTheme: ExpanderThemeData(
type: _expanderType,
modifier: _expanderModifier,
position: _expanderPosition,
color: Colors.grey.shade800,
size: 20,
),
labelStyle: TextStyle(
fontSize: 16,
letterSpacing: 0.3,
),
parentLabelStyle: TextStyle(
fontSize: 16,
letterSpacing: 0.1,
fontWeight: FontWeight.w800,
color: Colors.blue.shade700,
),
iconTheme: IconThemeData(
size: 18,
color: Colors.grey.shade800,
),
colorScheme: Theme.of(context).brightness == Brightness.light
? ColorScheme.light(
primary: Colors.blue.shade50,
onPrimary: Colors.grey.shade900,
background: Colors.transparent,
onBackground: Colors.black,
)
: ColorScheme.dark(
primary: Colors.black26,
onPrimary: Colors.white,
background: Colors.transparent,
onBackground: Colors.white70,
),
);
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
elevation: 0,
),
body: GestureDetector(
onTap: () {
FocusScope.of(context).requestFocus(FocusNode());
},
child: Container(
color: Colors.grey.shade200,
padding: EdgeInsets.all(20),
height: double.infinity,
child: Column(
children: <Widget>[
Container(
height: 300,
child: Column(
children: <Widget>[
_makeExpanderPosition(),
_makeExpanderType(),
_makeExpanderModifier(),
_makeAllowParentSelect(),
_makeSupportParentDoubleTap(),
],
),
),
Expanded(
child: Container(
decoration: BoxDecoration(
color: Colors.white,
borderRadius: BorderRadius.circular(10),
),
padding: EdgeInsets.all(10),
child: TreeView(
controller: _treeViewController,
allowParentSelect: _allowParentSelect,
supportParentDoubleTap: _supportParentDoubleTap,
onExpansionChanged: (key, expanded) =>
_expandNode(key, expanded),
onNodeTap: (key) {
debugPrint('Selected: $key');
setState(() {
_selectedNode = key;
_treeViewController =
_treeViewController.copyWith(selectedKey: key);
});
},
theme: _treeViewTheme,
),
),
),
GestureDetector(
onTap: () {
debugPrint('Close Keyboard');
FocusScope.of(context).unfocus();
},
child: Container(
padding: EdgeInsets.only(top: 20),
alignment: Alignment.center,
child: Text(_treeViewController.getNode(_selectedNode) == null
? ''
: _treeViewController.getNode(_selectedNode).label),
),
)
],
),
),
),
bottomNavigationBar: SafeArea(
top: false,
child: ButtonBar(
alignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
CupertinoButton(
child: Text('Node'),
onPressed: () {
setState(() {
_treeViewController = _treeViewController.copyWith(
children: _nodes,
);
});
},
),
CupertinoButton(
child: Text('JSON'),
onPressed: () {
setState(() {
_treeViewController =
_treeViewController.loadJSON(json: US_STATES_JSON);
});
},
),
CupertinoButton(
child: Text('Toggle'),
onPressed: _treeViewController.selectedNode != null &&
_treeViewController.selectedNode.isParent
? () {
setState(() {
_treeViewController = _treeViewController
.withToggleNode(_treeViewController.selectedKey);
});
}
: null,
),
CupertinoButton(
child: Text('Edit'),
onPressed: () {
TextEditingController editingController = TextEditingController(
text: _treeViewController.selectedNode.label);
showCupertinoDialog(
context: context,
builder: (context) {
return CupertinoAlertDialog(
title: Text('Edit Label'),
content: Container(
height: 80,
alignment: Alignment.center,
padding: EdgeInsets.all(10),
child: CupertinoTextField(
controller: editingController,
autofocus: true,
),
),
actions: <Widget>[
CupertinoDialogAction(
child: Text('Cancel'),
isDestructiveAction: true,
onPressed: () => Navigator.of(context).pop(),
),
CupertinoDialogAction(
child: Text('Update'),
isDefaultAction: true,
onPressed: () {
if (editingController.text.isNotEmpty) {
setState(() {
Node _node = _treeViewController.selectedNode;
_treeViewController =
_treeViewController.withUpdateNode(
_treeViewController.selectedKey,
_node.copyWith(
label: editingController.text));
});
debugPrint(editingController.text);
}
Navigator.of(context).pop();
},
),
],
);
});
},
),
],
),
),
);
}
_expandNode(String key, bool expanded) {
String msg = '${expanded ? "Expanded" : "Collapsed"}: $key';
debugPrint(msg);
Node node = _treeViewController.getNode(key);
if (node != null) {
List<Node> updated;
if (key == 'docs') {
updated = _treeViewController.updateNode(
key,
node.copyWith(
expanded: expanded,
icon: NodeIcon(
codePoint: expanded
? Icons.folder_open.codePoint
: Icons.folder.codePoint,
color: expanded ? "blue600" : "grey700",
)),
);
} else {
updated = _treeViewController.updateNode(
key, node.copyWith(expanded: expanded));
}
setState(() {
if (key == 'docs') docsOpen = expanded;
_treeViewController = _treeViewController.copyWith(children: updated);
});
}
}
}
class ModContainer extends StatelessWidget {
final ExpanderModifier modifier;
const ModContainer(this.modifier, {Key key}) : super(key: key);
@override
Widget build(BuildContext context) {
double _borderWidth = 0;
BoxShape _shapeBorder = BoxShape.rectangle;
Color _backColor = Colors.transparent;
Color _backAltColor = Colors.grey.shade700;
switch (modifier) {
case ExpanderModifier.none:
break;
case ExpanderModifier.circleFilled:
_shapeBorder = BoxShape.circle;
_backColor = _backAltColor;
break;
case ExpanderModifier.circleOutlined:
_borderWidth = 1;
_shapeBorder = BoxShape.circle;
break;
case ExpanderModifier.squareFilled:
_backColor = _backAltColor;
break;
case ExpanderModifier.squareOutlined:
_borderWidth = 1;
break;
}
return Container(
decoration: BoxDecoration(
shape: _shapeBorder,
border: _borderWidth == 0
? null
: Border.all(
width: _borderWidth,
color: _backAltColor,
),
color: _backColor,
),
width: 15,
height: 15,
);
}
}
const List<Map<String, dynamic>> US_STATES = [
{
"label": "A",
"children": [
{"label": "Alabama", "key": "AL"},
{"label": "Alaska", "key": "AK"},
{"label": "American Samoa", "key": "AS"},
{"label": "Arizona", "key": "AZ"},
{"label": "Arkansas", "key": "AR"}
]
},
{
"label": "C",
"children": [
{"label": "California", "key": "CA"},
{"label": "Colorado", "key": "CO"},
{"label": "Connecticut", "key": "CT"},
]
},
{
"label": "D",
"children": [
{"label": "Delaware", "key": "DE"},
{"label": "District Of Columbia", "key": "DC"},
]
},
{
"label": "F",
"children": [
{"label": "Federated States Of Micronesia", "key": "FM"},
{"label": "Florida", "key": "FL"},
]
},
{
"label": "G",
"children": [
{"label": "Georgia", "key": "GA"},
{"label": "Guam", "key": "GU"},
]
},
{
"label": "H",
"children": [
{"label": "Hawaii", "key": "HI"},
]
},
{
"label": "I",
"children": [
{"label": "Idaho", "key": "ID"},
{"label": "Illinois", "key": "IL"},
{"label": "Indiana", "key": "IN"},
{"label": "Iowa", "key": "IA"},
]
},
{
"label": "K",
"children": [
{"label": "Kansas", "key": "KS"},
{"label": "Kentucky", "key": "KY"},
]
},
{
"label": "L",
"children": [
{"label": "Louisiana", "key": "LA"},
]
},
{
"label": "M",
"children": [
{"label": "Maine", "key": "ME"},
{"label": "Marshall Islands", "key": "MH"},
{"label": "Maryland", "key": "MD"},
{"label": "Massachusetts", "key": "MA"},
{"label": "Michigan", "key": "MI"},
{"label": "Minnesota", "key": "MN"},
{"label": "Mississippi", "key": "MS"},
{"label": "Missouri", "key": "MO"},
{"label": "Montana", "key": "MT"},
]
},
{
"label": "N",
"children": [
{"label": "Nebraska", "key": "NE"},
{"label": "Nevada", "key": "NV"},
{"label": "New Hampshire", "key": "NH"},
{"label": "New Jersey", "key": "NJ"},
{"label": "New Mexico", "key": "NM"},
{"label": "New York", "key": "NY"},
{"label": "North Carolina", "key": "NC"},
{"label": "North Dakota", "key": "ND"},
{"label": "Northern Mariana Islands", "key": "MP"},
]
},
{
"label": "O",
"children": [
{"label": "Ohio", "key": "OH"},
{"label": "Oklahoma", "key": "OK"},
{"label": "Oregon", "key": "OR"},
]
},
{
"label": "P",
"children": [
{"label": "Palau", "key": "PW"},
{"label": "Pennsylvania", "key": "PA"},
{"label": "Puerto Rico", "key": "PR"},
]
},
{
"label": "R",
"children": [
{"label": "Rhode Island", "key": "RI"},
]
},
{
"label": "S",
"children": [
{"label": "South Carolina", "key": "SC"},
{"label": "South Dakota", "key": "SD"},
]
},
{
"label": "T",
"children": [
{"label": "Tennessee", "key": "TN"},
{"label": "Texas", "key": "TX"},
]
},
{
"label": "U",
"children": [
{"label": "Utah", "key": "UT"},
]
},
{
"label": "V",
"children": [
{"label": "Vermont", "key": "VT"},
{"label": "Virgin Islands", "key": "VI"},
{"label": "Virginia", "key": "VA"},
]
},
{
"label": "W",
"children": [
{"label": "Washington", "key": "WA"},
{"label": "West Virginia", "key": "WV"},
{"label": "Wisconsin", "key": "WI"},
{"label": "Wyoming", "key": "WY"}
]
},
];
String US_STATES_JSON = jsonEncode(US_STATES);
import'包装：flift/cupertino.dart'；
进口“包装：颤振/材料.省道”；
导入“package:flatter_treeview/tree_view.dart”；
导入“dart:convert”；
void main（）=>runApp（MyApp（））；
类MyApp扩展了无状态小部件{
//此小部件是应用程序的根。
@凌驾
小部件构建（构建上下文）{
返回材料PP(
标题：“TreeView示例”，
主页：MyHomePage（标题：“TreeView示例”），
);
}
}
类MyHomePage扩展StatefulWidget{
MyHomePage（{Key，this.title}）：超级（Key:Key）；
最后的字符串标题；
@凌驾
_MyHomePageState createState（）=>\u MyHomePageState（）；
}
类_MyHomePageState扩展状态{
字符串_selectedNode；
列表节点；
TreeView控制器\u TreeView控制器；
bool docsOpen=真；
最终地图扩展位置选项=常量{
ExpanderPosition.start:Text（'start'），
ExpanderPosition.end:文本（'end'），
};
最终映射扩展类型选项=常量{
ExpanderType.caret:图标(
Icons.arrow\u下拉菜单，
尺码：28，
),
ExpanderType.arrow：图标（图标。向下箭头），
ExpanderType.chevron:Icon（Icons.expand_more），
ExpanderType.plusMinus:Icon（Icons.add），
};
最终映射扩展ModifierOptions=const{
ExpanderModifier.none:ModContainer（ExpanderModifier.none），
ExpanderModifier.circleFilled:ModContainer（ExpanderModifier.circleFilled），
ExpanderModifier.circleOutlined：
ModContainer（ExpanderModifier.圆圈），
ExpanderModifier.squareFilled:ModContainer（ExpanderModifier.squareFilled），
ExpanderModifier.xml文件：
ModContainer（ExpanderModifier.square），
};
ExpanderPosition\u ExpanderPosition=ExpanderPosition.start；
ExpanderType _ExpanderType=ExpanderType.caret；
ExpanderModifier\u ExpanderModifier=ExpanderModifier.none；
bool _allowParentSelect=false；
bool\u supportParentDoubleTap=false；
@凌驾
void initState（）{
_节点=[
节点(
标签：“文件”，
关键字：“文档”，
扩展：docsOpen，
图标：NodeIcon(
代码点：
docsOpen？Icons.folder_open.codePoint:Icons.folder.codePoint，
颜色：“蓝色”，
),
儿童：[
节点(
标签：'个人'，
键：“d3”，
图标：NodeIcon.fromIconda（Icons.input），
儿童：[
节点(
标签：“Resume.docx”，
键：“pd1”，
图标：NodeIcon.fromIconda（Icons.insert\u drive\u file）），
节点(
标签：“求职信.docx”，
键：“pd2”，
图标：NodeIcon.fromIconda（Icons.insert\u drive\u file）），
]),
节点(
标签：“Inspection.docx”，
键：“d1”，
//图标：NodeIcon.fromIconda（图标.插入驱动器文件），
),
节点(
标签：“Invoice.docx”，
键：“d2”，
图标：NodeIcon.fromIconda（Icons.insert\u drive\u file）），
],
),
节点(
标签：“MeetingReport.xls”，
关键字：“mrxls”，
图标：NodeIcon.fromIconda（Icons.insert\u drive\u file）），
节点(
标签：“MeetingReport.pdf”，
关键字：“mrpdf”，
图标：NodeIcon.fromIconda（Icons.insert\u drive\u file）），
节点(
标签：“Demo.zip”，
键：“演示”，
图标：NodeIcon.fromiconda（Icons.archive）），
];
_TreeView控制器=TreeView控制器(
子节点：_节点，
selectedKey:\u selectedNode，
);
super.initState（）；
}
ListTile_makeExpanderPosition（）{
返回列表块(
标题：文本（“扩展器位置”），
是的，
尾部：CupertinoSlidingSegmentedControl(
子项：扩展位置选项，
groupValue:_expanderPosition，
onValueChanged:（ExpanderPosition newValue）{
设置状态（）{
_expanderPosition=newValue；
});
},
),
);
}
SwitchListTile_makeAllowParentSelect（）{
返回SwitchListTile.adaptive(
标题：文本（“允许父选择”），
是的，
值：_allowParentSelect，
一旦更改：（v）{
设置状态（）{
_allowParentSelect=v；
});
},
);
}
SwitchListTile_makeSupportParentDoubleTap（）{
返回SwitchListTile.adaptive(
标题：文本（“支持父双击”），
是的，
值：_supportParentDoubleTap，
一旦更改：（v）{
设置状态（）{
_supportParentDoubleTap=v；
});
},
);
}
ListTile_makeExpanderType（）{
返回列表块(
标题：文本（“扩展样式”），
是的，
尾部：CupertinoSlidingSegmentedControl(
子项：expansionTypeOptions，
groupValue:\u expanderType，
onValueChanged:（ExpanderType newValue）{
设置状态（）{
_expanderType=newValue；
});
},
),
);
}
ListTile_makeExpanderModifier（）{
返回列表块(
标题：文本（“扩展修饰符”），
是的，
尾部：CupertinoSlidingSegmentedControl(
子项：扩展修改器选项，
groupValue:\u expanderModifier，
onValueChanged:（扩展器）