如何使用颤振在共享首选项中保存布尔值？

Question

我一直在尝试在共享首选项中保存布尔值“DarkMode”，但似乎无法成功。 darkmode 变量用于将应用程序更改为暗模式。如果有人可以使用布尔值发布一个非常简单的共享偏好示例，也将不胜感激。任何帮助将不胜感激。谢谢

import 'package:flutter/material.dart';
import 'package:page_transition/page_transition.dart';
import 'package:shared_preferences/shared_preferences.dart';

bool DarkMode = false;    //Here is the code that I want to save into storage.
bool Afr = true;

class Gr8Videos extends StatefulWidget {
  //Gr8Videos({Key key, this.title}) : super(key: key);

  // final String title;

  @override
  _Gr8VideosState createState() => _Gr8VideosState();
}

class _Gr8VideosState extends State<Gr8Videos> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        drawer: Container(
          width: 160,
          child: ClipRRect(
            borderRadius: BorderRadius.vertical(top: Radius.circular(0.0)),
            child: Drawer(
              child: Container(
                color: DarkMode ? Colors.grey[900] : Colors.white,
                child: Padding(
                  padding: const EdgeInsets.fromLTRB(0, 30, 0, 0),
                  child: Column(
                    children: <Widget>[
                      Row(
                        children: <Widget>[
                          IconButton(
                            icon: Icon(
                              Icons.message,
                              size: 25,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                            onPressed: () {
                              //     Navigator.push(
                              //         context,
                              //         PageTransition(
                              //             type: PageTransitionType.rightToLeft,
                              //             child: SavedRoute()));
                            },
                          ),
                          Text(
                            'Contact',
                            style: TextStyle(
                              fontSize: 17,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                          ),
                        ],
                      ),
                      Row(
                        children: <Widget>[
                          IconButton(
                            icon: Icon(
                              Icons.notifications,
                              size: 25,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                            onPressed: () {
                              //     Navigator.push(
                              //         context,
                              //         PageTransition(
                              //             type: PageTransitionType.rightToLeft,
                              //             child: SavedRoute()));
                            },
                          ),
                          Text(
                            'Notifications',
                            style: TextStyle(
                              fontSize: 17,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                          ),
                        ],
                      ),
                      Row(
                        children: <Widget>[
                          IconButton(
                            icon: Icon(
                              Icons.share,
                              size: 25,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                            onPressed: () {
                              //     Navigator.push(
                              //         context,
                              //         PageTransition(
                              //             type: PageTransitionType.rightToLeft,
                              //             child: SavedRoute()));
                            },
                          ),
                          Text(
                            'Share',
                            style: TextStyle(
                              fontSize: 17,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                          ),
                        ],
                      ),
                      Row(
                        children: <Widget>[
                          IconButton(
                            icon: Icon(
                              Icons.settings,
                              size: 25,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                            onPressed: () {
                              //     Navigator.push(
                              //         context,
                              //         PageTransition(
                              //             type: PageTransitionType.rightToLeft,
                              //             child: SavedRoute()));
                            },
                          ),
                          Text(
                            'Settings',
                            style: TextStyle(
                              fontSize: 17,
                              color: DarkMode ? Colors.white : Colors.black,
                            ),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              ),
            ),
          ),
        ),
        appBar: AppBar(
          title: Text(
            'Welcome ' + Name,
            style: TextStyle(fontWeight: FontWeight.w400),
          ),
          backgroundColor: DarkMode ? Colors.grey[900] : Colors.blue, //Here is the code that I want to get form storage.
          centerTitle: true,
          actions: <Widget>[
            Row(...And so on

Answer 1

您可以将此库用于SharedPreference

我刚刚与您分享了如何使用共享偏好。你可以像其他人一样存储 bool。

将此添加到您的包的 pubspec.yaml 文件中：

依赖： shared_preferences: ^0.5.12+4

saveBoolVaue() async {
  SharedPreferences prefs = await SharedPreferences.getInstance();
  prefs.setBool('status', true);
 
}

getBoolVaue() async {
  SharedPreferences prefs = await SharedPreferences.getInstance();
  await prefs.getBool('status');
 
}