如何正确记录列表(todolist)的本地存储(共享引用)

Question

我是个新手。我有一项任务要为任务列表创建本地存储库。我尝试了许多选项来编写代码，但都不起作用。我看了很多视频和文章。请写下你的选择如何我可以记录它

这是我的代码：

import 'dart:convert';
import 'dart:collection';
import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/rendering.dart';
import 'package:shared_preferences/shared_preferences.dart';

class Home extends StatefulWidget {
const Home ({key}): super(key: key);
@override
State<Home> createState() => _HomeState();
}
class _HomeState extends State<Home> {
final myController = TextEditingController();
bool submit = false;
Color mainColor = Color(0xFFEEEFF5);
Color secColor = Color(0xFF3A3A3A);
Color tdBlue = Color(0xFF5F52EE);

String temp = "";
List todoList = [];
@override
void initState() {
super.initState();
myController.addListener(() {
setState(() {
submit = myController.text.isNotEmpty;
});
});
todoList.addAll(['Biy milk','Dishhh Wash','Придбати картоплю', 'Buy cucumbers', 'Kylunuch'],);
}
@override
void dispose() {
// Clean up the controller when the widget is disposed.
myController.dispose();
super.dispose();
}
void clearText() {
myController.clear();
}
@override
Widget build(BuildContext context){
return Scaffold(
backgroundColor: mainColor,
appBar: AppBar(
elevation: 0.0,
backgroundColor: secColor,
title: Text ('ToDo - List', style: TextStyle(fontSize: 26.5, fontWeight: FontWeight.bold, fontStyle: FontStyle.italic),),
),
body: Column(
children: [
Container(
margin: EdgeInsets.only(
top: 15.0,
left: 13.0,
right: 8.0,
),
child: Row(
children: [
Expanded(
child: TextField(
onChanged: (String value) {
temp = value;
},
controller: myController,
decoration:
InputDecoration(
prefixIcon: Icon(Icons.notes, color: Colors.orangeAccent,),
labelText: 'Замітка',
hintText: 'Введіть замітку',
filled: true,
fillColor: Colors.white,
border: OutlineInputBorder(),
contentPadding: EdgeInsets.all(10.0),
enabledBorder: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(30.0),),
),
),
),
),
SizedBox(
width: 10.0,
),
ElevatedButton(
style: ElevatedButton.styleFrom(backgroundColor: tdBlue),
onPressed:
submit ? () => submitData() : null,
child:
Text('+', style: TextStyle(fontSize: 35),),
),
], // Закривається 2-ий чілдрен
), //Row 1-ий
),
Expanded(
child: Padding(
padding: EdgeInsets.only(
top: 15.0,
),
child: ListView.builder(
itemCount: todoList.length,
itemBuilder: (BuildContext context, int index){
return Dismissible(
key: Key(todoList[index]),
child: Card(
margin: EdgeInsets.only(
top: 16.0,
left: 25.0,
right: 25.0,
),
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(25.0)),
elevation: 0.0,
child:
ListTile(
leading: Icon(Icons.delete_sweep, color: Colors.orangeAccent,),
title: Text(todoList[index],
),),
),
onDismissed: (direction){
if (direction == DismissDirection.endToStart) {
setState(() {
todoList.removeAt(index);
});// Закривається Сетстейт (")") і }
}
}, // Закривається ОнДісмісед
);
},
),
)
),
], // Закривається 1-ий чілдрен
),
);
}
submitData()  {
setState(() {
todoList.add(temp);
clearText();
});
} // submit data
}

我尝试了许多选项来编写代码，但都不起作用。

Answer 1

试试这个

List<String> todoList = [];
@override
void initState() {
super.initState();
myController.addListener(() {
setState(() {
submit = myController.text.isNotEmpty;
});
});
omLoadData();
}
submitData() async {
setState(() {
todoList.add(temp);
clearText();
});
SharedPreferences prefs = await SharedPreferences.getInstance();
await prefs.setStringList('todo_list', todoList);
}
omLoadData() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
final data = prefs.getStringList("todo_list");
todoList.addAll(data!);
}