Flutter本地存储插件simple_storage_plugin的使用

Flutter本地存储插件simple_storage_plugin的使用

simple_storage_plugin 是一个用于在Android设备上使用SharedPreferences存储数据的插件。它高度依赖于 simple_signing_plugin。存储的数据将使用AES进行加密。为了确保包能够正常工作，需要保护设备的屏幕锁。

特性

该插件包含以下方法：

1. writeData - 将用户输入和密钥保存到SharedPreferences中。执行此操作需要身份验证。
2. readData - 从SharedPreferences中读取保存在指定键下的数据。如果不存在这样的键，则会抛出异常。
3. deleteData - 从SharedPreferences中删除保存在指定键下的数据。
4. editData - 编辑保存在SharedPreferences中指定键下的数据。执行此操作需要身份验证。

使用示例

// 写入数据示例
String _data = '数据';
String _key = '键';
var result = await SimpleStoragePlugin.writeData(_key, _data); // 如果一切顺利返回true。可能会抛出SharedPreferencesException或DeviceNotSecuredException

// 读取数据示例
String _key = '键';
var result = await SimpleStoragePlugin.readData(_key); // 如果一切顺利返回写入的数据。可能会抛出InvalidSignatureException, DeviceNotSecuredException或NoKeyInStorageException

// 删除数据示例
String _key = '键';
var result = await SimpleStoragePlugin.deleteData(_key); // 如果一切顺利返回true。可能会抛出SharedPreferencesException或DeviceNotSecuredException

// 编辑数据示例
String _data = '数据';
String _key = '键';
var result = await SimpleStoragePlugin.editData(_key, _data); // 如果一切顺利返回true。可能会抛出SharedPreferencesException或DeviceNotSecuredException

完整示例Demo

以下是完整的示例代码，展示了如何在Flutter应用中使用 simple_storage_plugin 插件。

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

import 'package:flutter/services.dart';
import 'package:simple_storage_plugin/simple_storage_plugin.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : super(key: key);

  [@override](/user/override)
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  TextEditingController writeKeyController = TextEditingController();
  TextEditingController writeDataController = TextEditingController();
  TextEditingController readKeyController = TextEditingController();
  TextEditingController deleteKeyController = TextEditingController();
  TextEditingController editKeyController = TextEditingController();
  TextEditingController editDataController = TextEditingController();
  String writeResult = '';
  String readResult = '';
  String deleteResult = '';
  String editResult = '';

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('存储示例应用'),
        ),
        body: SingleChildScrollView(
          child: Center(
              child: Column(
            children: [
              const Text(
                '1. 写入',
                style: TextStyle(fontWeight: FontWeight.bold, fontSize: 25),
              ),
              TextFormField(
                controller: writeKeyController,
                decoration: const InputDecoration(hintText: "键"),
              ),
              TextFormField(
                controller: writeDataController,
                decoration: const InputDecoration(hintText: "数据"),
              ),
              RawMaterialButton(
                onPressed: () async {
                  if (writeDataController.text.isNotEmpty &&
                      writeKeyController.text.isNotEmpty) {
                    var result = await SimpleStoragePlugin.writeData(
                        writeKeyController.text, writeDataController.text);
                    if (result == true) {
                      setState(() {
                        writeResult = '成功！';
                      });
                    } else {
                      setState(() {
                        writeResult = '失败！';
                      });
                    }
                  }
                },
                child: const Text('写入！'),
              ),
              Text(writeResult),
              const Divider(),
              const Text(
                '2. 读取',
                style: TextStyle(fontWeight: FontWeight.bold, fontSize: 25),
              ),
              TextFormField(
                controller: readKeyController,
                decoration: const InputDecoration(hintText: "键"),
              ),
              RawMaterialButton(
                onPressed: () async {
                  if (readKeyController.text.isNotEmpty) {
                    var result = await SimpleStoragePlugin.readData(
                        readKeyController.text);
                    if (result != false) {
                      setState(() {
                        readResult = result;
                      });
                    } else {
                      setState(() {
                        readResult = '失败！';
                      });
                    }
                  }
                },
                child: const Text('读取！'),
              ),
              Text(readResult),
              const Divider(),
              const Text(
                '3. 删除',
                style: TextStyle(fontWeight: FontWeight.bold, fontSize: 25),
              ),
              TextFormField(
                controller: deleteKeyController,
                decoration: const InputDecoration(hintText: "键"),
              ),
              RawMaterialButton(
                onPressed: () async {
                  if (deleteKeyController.text.isNotEmpty) {
                    var result = await SimpleStoragePlugin.deleteData(
                        deleteKeyController.text);
                    if (result == true) {
                      setState(() {
                        deleteResult = "已删除！";
                      });
                    } else {
                      setState(() {
                        deleteResult = "失败！";
                      });
                    }
                  }
                },
                child: const Text('删除！'),
              ),
              Text(deleteResult),
              const Divider(),
              const Text(
                '4. 编辑',
                style: TextStyle(fontWeight: FontWeight.bold, fontSize: 25),
              ),
              TextFormField(
                controller: editKeyController,
                decoration: const InputDecoration(hintText: "键"),
              ),
              TextFormField(
                controller: editDataController,
                decoration: const InputDecoration(hintText: "数据"),
              ),
              RawMaterialButton(
                onPressed: () async {
                  if (editDataController.text.isNotEmpty &&
                      editKeyController.text.isNotEmpty) {
                    var result = await SimpleStoragePlugin.editData(
                        editKeyController.text, editDataController.text);
                    if (result == true) {
                      setState(() {
                        editResult = '成功！';
                      });
                    } else {
                      setState(() {
                        editResult = '失败！';
                      });
                    }
                  }
                },
                child: const Text('编辑！'),
              ),
              Text(editResult),
              const Divider(),
            ],
          )),
        ),
      ),
    );
  }
}