Flutter本地数据存储插件hive_storage的使用

Flutter本地数据存储插件hive_storage的使用

标题

hive_storage

内容

A new Flutter plugin project.

This project is a starting point for a Flutter plug-in package, a specialized package that includes platform-specific implementation code for Android and/or iOS.

For help getting started with Flutter development, view the online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.

示例代码

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:hive_storage/hive_storage.dart';

Future<void> main() async {
  await HiveStorageImp.hiveInjector();
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String get countKey => "countKey";
  int count = 0;

  @override
  void initState() {
    getData();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Hive Storage Example'),
        ),
        body: Center(
          child: Text('Value $count'),
        ),
        floatingActionButton: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            FloatingActionButton(
              child: const Icon(Icons.add),
              onPressed: () async {
                count = count + 1;
                await getHiveStorage.write(
                  value: count,
                  key: countKey,
                );
                getData();
              },
            ),
            const SizedBox(height: 10),
            FloatingActionButton(
              child: const Icon(Icons.minimize),
              onPressed: () async {
                count = count - 1;
                await getHiveStorage.write(
                  value: count,
                  key: countKey,
                );
                getData();
              },
            ),
            const SizedBox(height: 10),
            FloatingActionButton(
              child: const Icon(Icons.clear),
              onPressed: () =&gt; clearStorage(),
            ),
          ],
        ),
      ),
    );
  }

  void getData() {
    setState(() {
      _getCount();
    });
  }

  void _getCount() {
    count = getHiveStorage.read(key: countKey) ?? 0;
  }

  void clearStorage() async {
    await getHiveStorage.clearStorage();
    getData();
  }
}

解释

在上述示例代码中，我们使用了 hivestorage 插件来实现Flutter应用中的本地数据存储。以下是对代码的详细解释：

1. 导入必要的包：

   import 'dart:async';
   import 'package:flutter/material.dart';
   import 'package:hive_storage/hive_storage.dart';
   

   这些是用于构建Flutter应用和访问本地存储的必要包。

2. main函数：

Future<void> main() async {
  await HiveStorageImp.hiveInjector();
  runApp(const MyApp());
}

在这是程序的入口点，首先注入HiveStorage实例，然后创建并运行主应用实例。

1. MyApp类：

class MyApp extends StatefulWidget {
  const MyApp({required this.key});
  final Key key;
  @override
  State<MyApp> createState() => _MyAppState();
}

这是一个状态管理类，用于创建和管理应用的状态。

1. _MyAppState类：

class _MyAppState extends State<MyApp> {
  String get countKey => "countKey";
  int count = 0;

  @override
  void initState() {
    getData();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Hive Storage Example'),
        ),
        body: Center(
          child: Text('Value $count'),
        ),
        floatingActionButton: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            FloatingActionButton(
              child: const Icon(Icons.add),
              onPressed: () async {
                count = count + ；
                await getHiveStorage.write(
                  value: count,
                  key: countKey,
                );
                getData();
              },
            ),
            const SizedBox(height: ），
            FloatingActionButton(
              child: const Icon(Icons.minimize),
              onPressed: () async {
                count = count - ；
                await getHiveStorage.write(
                  value: count,
                  key: countKey,
                );
                getData();
              },
            ),
            const SizedBox(height: ），
            FloatingActionButton(
              child: const Icon(Icons.clear),
              onPressed: () => clearStorage(),
            ),
          ],
        ),
      ),
    );
  }

  void getData() {
    setState(() {
      _getCount();
    });
  }

  void _getCount() {
    count = getHiveStorage.read(key: countKey) ?? 0;
  }

  void clearStorage() async {
    await getHiveStorage.clearStorage();
    getData();
  }
}