如何制作可编辑的ListView项

Question

我有动态数据，我正在使用ListView.builder向用户显示。我只是使用一个文本来向用户显示数据。我只添加了一个编辑图标，这样当用户单击该图标时，用户就可以编辑特定的文本。如何制作可编辑的ListView项？

Answer 1

您应该将以下类调用到itemBuilder:，filed of ListView.builder(…(

class ListItem extends StatefulWidget {
@override
_ListItemState createState() => _ListItemState();
}
class _ListItemState extends State<ListItem> {
bool _isEnabled = false;
@override
Widget build(BuildContext context) {
return ListTile(
title: TextField(
enabled: _isEnabled,
decoration: InputDecoration(
hintText: 'Enter a text',
),
),
// The icon button which will notify list item to change
trailing: GestureDetector(
child: new Icon(
Icons.edit,
color: Colors.black,
),
onTap: () {
setState((){
_isEnabled = !_isEnabled;
});
},
),
);
}
}

Answer 2

您可以使用TextField的可编辑字段使TextField可编辑或不可编辑。

import 'package:flutter/material.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
// This is the theme of your application.
//
// Try running your application with "flutter run". You'll see the
// application has a blue toolbar. Then, without quitting the app, try
// changing the primarySwatch below to Colors.green and then invoke
// "hot reload" (press "r" in the console where you ran "flutter run",
// or press Run > Flutter Hot Reload in IntelliJ). Notice that the
// counter didn't reset back to zero; the application is not restarted.
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
// This widget is the home page of your application. It is stateful, meaning
// that it has a State object (defined below) that contains fields that affect
// how it looks.
// This class is the configuration for the state. It holds the values (in this
// case the title) provided by the parent (in this case the App widget) and
// used by the build method of the State. Fields in a Widget subclass are
// always marked "final".
final String title;
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
// This call to setState tells the Flutter framework that something has
// changed in this State, which causes it to rerun the build method below
// so that the display can reflect the updated values. If we changed
// _counter without calling setState(), then the build method would not be
// called again, and so nothing would appear to happen.
_counter++;
});
}
@override
Widget build(BuildContext context) {
// This method is rerun every time setState is called, for instance as done
// by the _incrementCounter method above.
//
// The Flutter framework has been optimized to make rerunning build methods
// fast, so that you can just rebuild anything that needs updating rather
// than having to individually change instances of widgets.
return new Scaffold(
appBar: new AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: new Text(widget.title),
),
body: Container(
child: ListView(
children: List.generate(100, (index){
return MyTile(index: index);  
}),
)
)
);
}
}
class MyTile extends StatefulWidget {
final int index;
MyTile({Key key, this.index}): super(key: key);
@override
_MyTileState createState() => _MyTileState();
}
// A custom list tile
class _MyTileState extends State<MyTile> {
// Initalliy make the TextField uneditable.
bool editable = false;
@override
Widget build(BuildContext context) {
return Container(
width: double.infinity,
padding: EdgeInsets.symmetric(horizontal: 10.0),
margin: EdgeInsets.only(bottom: 10.0),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Expanded(
child: TextField(           
enabled: editable,
decoration: InputDecoration(
hintText: "Index ${widget.index}",
hintStyle: TextStyle(color: Colors.black)                
),
onEditingComplete: (){
// After editing is complete, make the editable false
setState(() {
editable = !editable;                
});
},
),
),
RaisedButton(
elevation: 1.0,
child: Text('Edit'),
onPressed: (){
// When edit is pressed, make the editable true
setState(() {
editable = !editable;                
});
},
)
],
),
);
}
}

Answer 3

我尝试过使用textfield，但在中等滚动表中它非常昂贵。。。行不通的

解决方案是只使用文本来显示字段，当处于编辑模式时，我会显示一个对话框，或者将该行中的所有文本替换为文本字段。。。