API 30及以上版本如何检测网络连接？NetworkCapabilities错误求助

错误原因 #

你误用了API方法：hasCapability()要求传入NetworkCapabilities.NET_CAPABILITY_*系列的能力常量，而TRANSPORT_WIFI、TRANSPORT_CELLULAR属于网络传输类型标识，应该用hasTransport()方法来判断。

修正后的代码 #

fun checkInternetConnection(context: Context): Boolean {
    val connectivityManager = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    val network = connectivityManager.activeNetwork ?: return false
    val networkCapabilities = connectivityManager.getNetworkCapabilities(network) ?: return false

    return when {
        networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> true
        networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> true
        networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET) -> true
        else -> false
    }
}

进阶优化（可选） #

如果需要确保网络真正能访问互联网（而非仅连接上网络），建议同时验证网络有效性：

fun checkValidInternetConnection(context: Context): Boolean {
    val connectivityManager = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    val network = connectivityManager.activeNetwork ?: return false
    val networkCapabilities = connectivityManager.getNetworkCapabilities(network) ?: return false

    return networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET) &&
           networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)
}

内容的提问来源于stack exchange，提问作者Berkay Sazak