Android全局网络监控最佳实践（Kotlin实现）

本文将介绍如何在Android应用中实现全局网络状态监控，适配高版本API，并提供完整的Kotlin实现方案。

一、核心实现方案

1. 网络监控核心类

@SuppressLint("MissingPermission")
class NetworkMonitor private constructor(private val context: Context) {// 网络状态变化回调sealed interface NetworkStatus {object Available : NetworkStatusobject Lost : NetworkStatusdata class Changed(val type: NetworkType) : NetworkStatus}private val connectivityManager by lazy {context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager}private val _networkStatus = MutableSharedFlow<NetworkStatus>()val networkStatus = _networkStatus.asSharedFlow()private val callback = object : ConnectivityManager.NetworkCallback() {override fun onAvailable(network: Network) {postStatus(NetworkStatus.Available)}override fun onLost(network: Network) {postStatus(NetworkStatus.Lost)}override fun onCapabilitiesChanged(network: Network,capabilities: NetworkCapabilities) {val type = when {capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> NetworkType.WIFIcapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> NetworkType.CELLULARcapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET) -> NetworkType.ETHERNETelse -> NetworkType.UNKNOWN}postStatus(NetworkStatus.Changed(type))}}fun register() {val request = NetworkRequest.Builder().addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET).addCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED).build()connectivityManager.registerNetworkCallback(request, callback)}fun unregister() {try {connectivityManager.unregisterNetworkCallback(callback)} catch (e: IllegalArgumentException) {// 忽略未注册的异常}}private fun postStatus(status: NetworkStatus) {MainScope().launch {_networkStatus.emit(status)}}companion object {@Volatileprivate var instance: NetworkMonitor? = nullfun getInstance(context: Context): NetworkMonitor =instance ?: synchronized(this) {instance ?: NetworkMonitor(context.applicationContext).also { instance = it }}}
}enum class NetworkType {WIFI, CELLULAR, ETHERNET, UNKNOWN
}

2. Application初始化

class MyApp : Application() {override fun onCreate() {super.onCreate()NetworkMonitor.getInstance(this).register()}
}

在AndroidManifest.xml中注册：

<applicationandroid:name=".MyApp"...>
</application>

二、使用示例

1. Activity/Fragment中使用

class MainActivity : AppCompatActivity() {private var networkJob: Job? = nulloverride fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_main)observeNetworkStatus()}private fun observeNetworkStatus() {networkJob = lifecycleScope.launch {NetworkMonitor.getInstance(this@MainActivity).networkStatus.collect { status ->when (status) {is NetworkMonitor.NetworkStatus.Available -> {showNetworkConnected()}is NetworkMonitor.NetworkStatus.Lost -> {showNetworkDisconnected()}is NetworkMonitor.NetworkStatus.Changed -> {updateNetworkType(status.type)}}}}}private fun showNetworkConnected() {Toast.makeText(this, "网络已连接", Toast.LENGTH_SHORT).show()binding.networkStatusIndicator.setBackgroundColor(Color.GREEN)}private fun showNetworkDisconnected() {Toast.makeText(this, "网络已断开", Toast.LENGTH_SHORT).show()binding.networkStatusIndicator.setBackgroundColor(Color.RED)}private fun updateNetworkType(type: NetworkType) {val typeText = when (type) {NetworkType.WIFI -> "WiFi网络"NetworkType.CELLULAR -> "移动网络"NetworkType.ETHERNET -> "有线网络"NetworkType.UNKNOWN -> "未知网络"}binding.networkTypeText.text = "当前网络: $typeText"}override fun onDestroy() {super.onDestroy()networkJob?.cancel()}
}

2. ViewModel中使用

class MyViewModel(application: Application) : AndroidViewModel(application) {private val monitor = NetworkMonitor.getInstance(application)val networkStatus = monitor.networkStatus.stateIn(viewModelScope,started = SharingStarted.WhileSubscribed(5000),initialValue = NetworkMonitor.NetworkStatus.Available)
}

三、兼容性处理

1. 权限声明

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

2. 低版本兼容检查

fun checkNetworkAvailable(): Boolean {return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {val activeNetwork = connectivityManager.activeNetworkval capabilities = connectivityManager.getNetworkCapabilities(activeNetwork)capabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) == true &&capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)} else {@Suppress("DEPRECATION")connectivityManager.activeNetworkInfo?.isConnected == true}
}

四、高级功能扩展

1. 检测网络质量

fun getNetworkQuality(): NetworkQuality {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {val activeNetwork = connectivityManager.activeNetworkval capabilities = connectivityManager.getNetworkCapabilities(activeNetwork)return when {capabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_ROAMING) == false -> NetworkQuality.ROAMINGcapabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED) == false -> NetworkQuality.METEREDcapabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_CONGESTED) == false -> NetworkQuality.CONGESTEDelse -> NetworkQuality.GOOD}}return NetworkQuality.UNKNOWN
}enum class NetworkQuality {GOOD, METERED, ROAMING, CONGESTED, UNKNOWN
}

2. 监听特定网络状态

fun observeWifiStatus(): Flow<Boolean> = networkStatus.map { status ->when (status) {is NetworkStatus.Changed -> status.type == NetworkType.WIFIelse -> false}}.distinctUntilChanged()

五、最佳实践建议

1. 生命周期管理：确保在适当的生命周期注册和注销监听
2. 错误处理：添加适当的异常处理
3. 线程安全：确保网络状态更新在主线程执行UI操作
4. 性能优化：避免频繁的网络状态检查
5. 用户体验：提供友好的网络状态提示

六、总结

本文介绍了Android全局网络监控的完整实现方案，具有以下特点：

• 使用现代Android API（NetworkCallback）
• 支持响应式编程（Flow）
• 提供详细的网络状态信息
• 良好的兼容性处理
• 易于扩展的高级功能

这种实现方式适用于大多数现代Android应用，能够有效监控网络状态变化，为用户提供更好的网络体验。