问当Android/GoogleTV与WAN断开连接时收听
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Stack Overflow用户

提问于 2013-07-30 02:29:19

回答 1查看 263关注 0票数 0

我要监听GoogleTV设备断开连接的时间，然后显示弹出警告。

我认为我已经通过下面的代码实现了这一点，但随后发现，只有当设备的以太网电缆断开连接时才会警告我断开连接:即LAN。当路由器的输入以太网电缆断开时，我不会收到警报:即WAN。

我发现，当断开LAN电缆时，GTV设备将失去其IP地址，但当断开WAN电缆时，GTV设备仍将具有IP地址-这就是为什么我没有收到应用程序断开连接的警报的原因。

那么，当GoogleTV设备不再连接到广域网时，我如何检查？要做到这一点，我需要在下面的代码中添加什么？

startListeningToNetwork();
private void startListeningToNetwork() {
   if(_networkStateReceiver == null){
      //Listen for when the network changes. If app loses internet before webView has loaded, then display error message.
      _networkStateReceiver = new BroadcastReceiver() {
          @Override
          public void onReceive(Context context, Intent intent) {
            if(!isConnected()){
              showNetworkErrorDialog();
            } else {
                      closeNetworkError();
            }
          }

      };


      IntentFilter networkFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION); 

      getActivity().registerReceiver(_networkStateReceiver, networkFilter);
   }

}
private boolean isConnected() {
    ConnectivityManager cm = (ConnectivityManager) getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
    Toast.makeText(getActivity(), "isConnected? " + (cm.getActiveNetworkInfo() != null  && cm.getActiveNetworkInfo().isConnected()) , Toast.LENGTH_SHORT).show();
    return (cm.getActiveNetworkInfo() != null  && cm.getActiveNetworkInfo().isConnected());
}

android

google-tv

回答 1

Stack Overflow用户

发布于 2013-07-31 15:24:38

为BroadcastReceiver注册CONNECTIVITY_ACTION

您可以尝试以下两个选项：

- Use the `Context` that `BroadcastReceiver` is passed with to get the `ConnectivityManager`  and get current info about any active network
- Use parcerable [extras](http://developer.android.com/reference/android/net/ConnectivityManager.html#EXTRA_EXTRA_INFO) sent to the `Intent`

获取从点1

中的任一选项获取的活动网络的详细状态

公共类LANConnectionReceiver扩展了BroadcastReceiver{

    @Override
    public void onReceive(Context context, Intent i) {

            NetworkInfo info = (NetworkInfo)i.getParcelableExtra(ConnectivityManager.EXTRA_EXTRA_INFO);
            /*or use the context to get the connection manager whenever the broadcast is sent to this receiver 
             * ConnectivityManager conmng = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); 
                NetworkInfo activeNetwork = conmng.getActiveNetworkInfo();
             */
            Log.d("ConnectionReceiver", "State=" + info.getDetailedState());
            if(info.getType() ==ConnectivityManager.TYPE_ETHERNET){ //optional, we are interested in case when it looses WAN 
                switch(info.getDetailedState()){
                case AUTHENTICATING:
                    break;
                case BLOCKED:
                    break;
                case CAPTIVE_PORTAL_CHECK:
                    break;
                case CONNECTED:
                    break;
                case CONNECTING:
                    break;
                case DISCONNECTED:
                    break;
                case DISCONNECTING:
                    break;
                case FAILED:
                    break;
                case IDLE:
                    break;
                case OBTAINING_IPADDR:
                    break;
                case SCANNING:
                    break;
                case SUSPENDED:
                    break;
                case VERIFYING_POOR_LINK:
                    break;
                default:
                    break;

                }
            }
    }



}

注意，我们对网络的类型不感兴趣，因为我们感兴趣的是电视是否可以访问广域网，这就是为什么我将条件info.getType()==ConnectivityManager.TYPE_ETHERNET设置为可选的原因。

编辑：在上面的评论中，我提到了在不阻止应用程序的情况下递归检查网络。

public void listenForConnection(final Context c, final Handler h){
                h.postAtFrontOfQueue(new Runnable(){

                    @Override
                    public void run() {
                         ConnectivityManager cm = (ConnectivityManager) c.getSystemService(Context.CONNECTIVITY_SERVICE);
                        NetworkInfo networkInfo = cm.getActiveNetworkInfo();
                        if(networkInfo!=null && networkInfo.isConnectedOrConnecting()){
                            Intent i = new Intent(ConnectivityManager.CONNECTIVITY_ACTION);
                            i.putExtra(ConnectivityManager.EXTRA_NETWORK_TYPE, networkInfo.getType());
                            i.putExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false);
                            i.putExtra(ConnectivityManager.EXTRA_IS_FAILOVER, networkInfo.isFailover());
                            i.putExtra("MY_CUSTOM_KEY_HAS_WAN", true);
                            c.sendBroadcast(i);
                        }else {
                            //do something else
                        }
                        h.postDelayed(this, 100);
                    }});
            }