如何替换已废弃的ConnectivityManager.allNetworks网络检测代码

前置条件 #

首先需要在AndroidManifest.xml中声明网络状态访问权限：

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

你代码中被标记废弃的allNetworks是Android 12（API 31）起废弃的字段API，官方推荐按业务场景选择以下替换方案：

方案1：常用场景 - 实时监听网络状态（推荐） #

原代码中已经注册了DefaultNetworkCallback，我们可以直接结合回调能力更精准的监听网络变化，避免频繁主动轮询，替换后的完整代码如下：

private val isNetworkAvailable = MutableStateFlow(false)
// 保存回调实例用于后续注销，避免内存泄漏
private var networkCallback: ConnectivityManager.NetworkCallback? = null

fun checkNetworkAvailability(context: Context): MutableStateFlow<Boolean> {
    val connectivityManager =
        context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    networkCallback = object : ConnectivityManager.NetworkCallback() {
        override fun onAvailable(network: Network) {
            super.onAvailable(network)
            updateNetworkStatus(connectivityManager)
        }

        override fun onLost(network: Network) {
            super.onLost(network)
            updateNetworkStatus(connectivityManager)
        }

        override fun onCapabilitiesChanged(
            network: Network,
            networkCapabilities: NetworkCapabilities
        ) {
            super.onCapabilitiesChanged(network, networkCapabilities)
            updateNetworkStatus(connectivityManager)
        }
    }

    // 注册网络变化回调
    connectivityManager.registerDefaultNetworkCallback(networkCallback!!)

    // 首次调用时初始化当前网络状态
    updateNetworkStatus(connectivityManager)

    return isNetworkAvailable
}

private fun updateNetworkStatus(connectivityManager: ConnectivityManager) {
    val hasValidInternet = connectivityManager.activeNetwork?.let { network ->
        val capabilities = connectivityManager.getNetworkCapabilities(network)
        // 同时校验网络是否具备互联网能力、且已通过连通性验证
        capabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) == true
                && capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)
    } ?: false
    isNetworkAvailable.value = hasValidInternet
}

// 请在组件销毁/不需要监听时调用该方法注销回调，避免内存泄漏
fun stopNetworkListener(context: Context) {
    val connectivityManager =
        context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
    networkCallback?.let {
        connectivityManager.unregisterNetworkCallback(it)
        networkCallback = null
    }
}

方案2：单次查询所有网络状态（替换原有遍历逻辑） #

如果你确实需要遍历所有已注册的网络判断是否有可用网络，直接将原遍历部分的connectivityManager.allNetworks替换为connectivityManager.getAllNetworks()即可，该方法兼容API 21及以上版本，是官方指定的替代API：

var isConnected = false
// 替换原废弃的allNetworks字段
connectivityManager.getAllNetworks().forEach { network ->
    val networkCapability = connectivityManager.getNetworkCapabilities(network)
    networkCapability?.let {
        if(it.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) 
            && it.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)) {
            isConnected = true
            return@forEach
        }
    }
}

低版本兼容说明 #

如果你的应用minSdk低于23，需要补充版本判断兼容旧版本系统：

val isConnected = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    connectivityManager.activeNetwork?.let { network ->
        val capabilities = connectivityManager.getNetworkCapabilities(network)
        capabilities?.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) == true
    } ?: false
} else {
    @Suppress("DEPRECATION")
    connectivityManager.activeNetworkInfo?.isConnected == true
}

内容的提问来源于stack exchange，提问作者Stefan