NetworkInfo 总是返回 null

Question

我在以太网连接方面遇到了一些问题，特别是 NetworkInfo class 总是返回 null。

我实际上正在使用这段代码：

ConnectivityManager connManager = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE); //not null
        NetworkInfo networkInfo = connManager.getNetworkInfo(ConnectivityManager.TYPE_ETHERNET);  //null
        return networkInfo != null && networkInfo.isConnected();

我正在尝试建立以太网连接，有人可以帮助我吗？ 提前致谢！

Answer 1

对于以太网尝试如下

public Boolean isEthernetConnected(){
    if(isNetworkAvailable()){
        ConnectivityManager cm 
        = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        return (cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_ETHERNET);
    }
    return false;
}

 private Boolean isNetworkAvailable() {
    ConnectivityManager connectivityManager 
          = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
    return activeNetworkInfo != null && activeNetworkInfo.isConnectedOrConnecting();
}