Flutter设备指标获取插件flutter_metrics的使用

flutter_metrics 是一个用于获取设备指标的 Flutter 插件。它可以帮助开发者获取设备的硬件和软件信息，例如 CPU 使用率、内存使用情况、电池状态等。以下是如何使用 flutter_metrics 插件的基本步骤：

1. 添加依赖

首先，你需要在 pubspec.yaml 文件中添加 flutter_metrics 插件的依赖：

dependencies:
  flutter:
    sdk: flutter
  flutter_metrics: ^1.0.0  # 请使用最新版本

然后运行 flutter pub get 来获取依赖。

2. 导入插件

在你的 Dart 文件中导入 flutter_metrics 插件：

import 'package:flutter_metrics/flutter_metrics.dart';

3. 获取设备指标

flutter_metrics 提供了多种方法来获取设备的不同指标。以下是一些常见的用法：

获取 CPU 使用率

double cpuUsage = await FlutterMetrics.cpuUsage();
print('CPU Usage: $cpuUsage%');

获取内存使用情况

MemoryInfo memoryInfo = await FlutterMetrics.memoryInfo();
print('Total Memory: ${memoryInfo.totalMemory}');
print('Used Memory: ${memoryInfo.usedMemory}');
print('Free Memory: ${memoryInfo.freeMemory}');

获取电池状态

BatteryInfo batteryInfo = await FlutterMetrics.batteryInfo();
print('Battery Level: ${batteryInfo.batteryLevel}%');
print('Is Charging: ${batteryInfo.isCharging}');

获取存储信息

StorageInfo storageInfo = await FlutterMetrics.storageInfo();
print('Total Storage: ${storageInfo.totalStorage}');
print('Used Storage: ${storageInfo.usedStorage}');
print('Free Storage: ${storageInfo.freeStorage}');

4. 处理权限

在某些情况下，获取设备指标可能需要特定的权限（例如读取电池状态或存储信息）。请确保在 AndroidManifest.xml 和 Info.plist 中添加相应的权限声明。

Android

在 AndroidManifest.xml 中添加以下权限：

<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

iOS

在 Info.plist 中添加以下权限：

<key>NSBatteryUsageDescription</key>
<string>We need access to battery information to optimize your experience.</string>

5. 处理异常

在使用 flutter_metrics 时，可能会遇到平台不支持或权限不足的情况。建议在使用时进行异常处理：

try {
  double cpuUsage = await FlutterMetrics.cpuUsage();
  print('CPU Usage: $cpuUsage%');
} catch (e) {
  print('Failed to get CPU usage: $e');
}

6. 示例代码

以下是一个完整的示例代码，展示了如何使用 flutter_metrics 获取设备的各种指标：

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: DeviceMetricsScreen(),
    );
  }
}

class DeviceMetricsScreen extends StatefulWidget {
  @override
  _DeviceMetricsScreenState createState() => _DeviceMetricsScreenState();
}

class _DeviceMetricsScreenState extends State<DeviceMetricsScreen> {
  double cpuUsage = 0.0;
  MemoryInfo memoryInfo = MemoryInfo(0, 0, 0);
  BatteryInfo batteryInfo = BatteryInfo(0, false);
  StorageInfo storageInfo = StorageInfo(0, 0, 0);

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

  Future<void> fetchMetrics() async {
    try {
      cpuUsage = await FlutterMetrics.cpuUsage();
      memoryInfo = await FlutterMetrics.memoryInfo();
      batteryInfo = await FlutterMetrics.batteryInfo();
      storageInfo = await FlutterMetrics.storageInfo();
    } catch (e) {
      print('Failed to fetch metrics: $e');
    }
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Device Metrics'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text('CPU Usage: ${cpuUsage.toStringAsFixed(2)}%'),
            Text('Total Memory: ${memoryInfo.totalMemory} MB'),
            Text('Used Memory: ${memoryInfo.usedMemory} MB'),
            Text('Free Memory: ${memoryInfo.freeMemory} MB'),
            Text('Battery Level: ${batteryInfo.batteryLevel}%'),
            Text('Is Charging: ${batteryInfo.isCharging}'),
            Text('Total Storage: ${storageInfo.totalStorage} GB'),
            Text('Used Storage: ${storageInfo.usedStorage} GB'),
            Text('Free Storage: ${storageInfo.freeStorage} GB'),
          ],
        ),
      ),
    );
  }
}

7. 运行项目

确保你的设备或模拟器已经连接，然后运行项目：

flutter run