Как обнаружить устройства, подключенные к сети Wif

Question

Здравствуйте

Есть ли у вас идея, как обнаружить устройства, подключенные к сети Wi-Fi? Я использовал этот исходный код Java для обнаружения устройств, подключенных к домашней сети:

import java.io.IOException; 
import java.net.ServerSocket; 



import android.net.nsd.NsdManager; 
import android.net.nsd.NsdManager.DiscoveryListener; 
import android.net.nsd.NsdManager.RegistrationListener; 
import android.net.nsd.NsdManager.ResolveListener; 
import android.net.nsd.NsdServiceInfo; 
import android.os.Bundle; 
import android.annotation.SuppressLint; 
import android.app.Activity; 
import android.content.Context; 
import android.util.Log; 
import android.view.Menu; 

@SuppressLint("NewApi") 
public class MainActivity extends Activity { 

    NsdManager.RegistrationListener mRegistrationListener; 
    NsdManager.DiscoveryListener mDiscoveryListener; 

    String mServiceName; 
    NsdServiceInfo mServiceInfo; 
    ServerSocket mServerSocket; 
    int mLocalPort; 

    NsdManager mNsdManager; 

    final String TAG = "---Networking"; 
    final String SERVICE_TYPE = "_http._tcp."; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     // Initialize a server socket on the next available port. 
     try { 
      mServerSocket = new ServerSocket(0); 
     } catch (IOException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 
     // Store the chosen port. 
     mLocalPort = mServerSocket.getLocalPort(); 
     registerService(mLocalPort); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.menu_main, menu); 
     return true; 
    } 

    public void registerService(int port) { 
     // Create the NsdServiceInfo object, and populate it. 
     mServiceInfo = new NsdServiceInfo(); 

     // The name is subject to change based on conflicts 
     // with other services advertised on the same network. 

     mServiceInfo.setServiceName("NsdChat"); 
     mServiceInfo.setServiceType("_http._tcp."); 
     mServiceInfo.setPort(port); 

     mNsdManager = (NsdManager) getApplicationContext().getSystemService(Context.NSD_SERVICE); 

     initializeRegistrationListener(); 
     initializeDiscoveryListener(); 

     mNsdManager.registerService(
       mServiceInfo, NsdManager.PROTOCOL_DNS_SD, mRegistrationListener); 

     mNsdManager.discoverServices(
       SERVICE_TYPE, NsdManager.PROTOCOL_DNS_SD, mDiscoveryListener); 
    } 

    public void initializeRegistrationListener() { 
     mRegistrationListener = new NsdManager.RegistrationListener() { 

      @Override 
      public void onServiceRegistered(NsdServiceInfo NsdServiceInfo) { 
       // Save the service name. Android may have changed it in order to 
       // resolve a conflict, so update the name you initially requested 
       // with the name Android actually used. 
       mServiceName = NsdServiceInfo.getServiceName(); 
       Log.d(TAG, "Service name: " + mServiceName); 
       Log.d(TAG , "Port number: " + mLocalPort); 
      } 

      @Override 
      public void onRegistrationFailed(NsdServiceInfo serviceInfo, int errorCode) { 
       // Registration failed! Put debugging code here to determine why. 
       Log.d(TAG , "Registration Failed! Error code: " + errorCode); 
      } 

      @Override 
      public void onServiceUnregistered(NsdServiceInfo arg0) { 
       // Service has been unregistered. This only happens when you call 
       // NsdManager.unregisterService() and pass in this listener. 
       Log.d(TAG , "Service unregistered."); 
      } 

      @Override 
      public void onUnregistrationFailed(NsdServiceInfo serviceInfo, int errorCode) { 
       // Unregistration failed. Put debugging code here to determine why. 
       Log.d(TAG , "Unregistration failed!"); 
      } 
     }; 
    } 

    public void initializeDiscoveryListener() { 

     // Instantiate a new DiscoveryListener 
     mDiscoveryListener = new NsdManager.DiscoveryListener() { 

      // Called as soon as service discovery begins. 
      @Override 
      public void onDiscoveryStarted(String regType) { 
       Log.d(TAG , "Service discovery started"); 
      } 

      @Override 
      public void onServiceFound(NsdServiceInfo service) { 
       // A service was found! Do something with it. 
       Log.d(TAG, "Service discovery success: " + service); 
       if (!service.getServiceType().equals(SERVICE_TYPE)) { 
        // Service type is the string containing the protocol and 
        // transport layer for this service. 
        Log.d(TAG, "Unknown Service Type: " + service.getServiceType()); 
       } else if (service.getServiceName().equals(mServiceName)) { 
        // The name of the service tells the user what they'd be 
        // connecting to. It could be "Bob's Chat App". 
        Log.d(TAG, "Same machine: " + mServiceName); 
       } else if (service.getServiceName().contains("NsdChat")){ 
        mNsdManager.resolveService(service, new NsdManager.ResolveListener() { 

         @Override 
         public void onServiceResolved(NsdServiceInfo serviceInfo) { 
          // TODO Auto-generated method stub 
          Log.d(TAG, "Resolving service..."); 
         } 

         @Override 
         public void onResolveFailed(NsdServiceInfo serviceInfo, int errorCode) { 
          // TODO Auto-generated method stub 
          Log.d(TAG, "Service resolve failed!"); 
         } 
        }); 
       } 
      } 

      @Override 
      public void onServiceLost(NsdServiceInfo service) { 
       // When the network service is no longer available. 
       // Internal bookkeeping code goes here. 
       Log.e(TAG, "service lost: " + service); 
      } 

      @Override 
      public void onDiscoveryStopped(String serviceType) { 
       Log.i(TAG, "Discovery stopped: " + serviceType); 
      } 

      @Override 
      public void onStartDiscoveryFailed(String serviceType, int errorCode) { 
       Log.e(TAG, "Discovery failed: Error code: " + errorCode); 
       mNsdManager.stopServiceDiscovery(this); 
      } 

      @Override 
      public void onStopDiscoveryFailed(String serviceType, int errorCode) { 
       Log.e(TAG, "Discovery failed: Error code: " + errorCode); 
       mNsdManager.stopServiceDiscovery(this); 
      } 
     }; 
    } 
} 

Но у меня есть этот результат. В этом случае номер порта и имя узла имеют значение NULL.

02-15 19:10:58.205 21554-21554/com.example.fatma.myapplication W/asset﹕ AssetManager-->addDefaultAssets CIP path not exsit! 
    02-15 19:10:58.490 21554-21554/com.example.fatma.myapplication V/PhoneWindow﹕ DecorView setVisiblity: visibility = 4 
    02-15 19:10:58.567 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery started 
    02-15 19:10:58.572 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChattype: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:58.594 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChattype: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:58.597 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChat (2)type: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:58.598 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChat (2)type: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:58.598 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service resolve failed! 
    02-15 19:10:58.599 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service resolve failed! 
    02-15 19:10:58.601 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service resolve failed! 
    02-15 19:10:58.625 21554-21554/com.example.fatma.myapplication V/PhoneWindow﹕ DecorView setVisiblity: visibility = 0 
    02-15 19:10:58.835 21554-21554/com.example.fatma.myapplication D/libEGL﹕ loaded /system/lib/egl/libEGL_mali.so 
    02-15 19:10:58.859 21554-21554/com.example.fatma.myapplication D/libEGL﹕ loaded /system/lib/egl/libGLESv1_CM_mali.so 
    02-15 19:10:58.879 21554-21554/com.example.fatma.myapplication D/libEGL﹕ loaded /system/lib/egl/libGLESv2_mali.so 
    02-15 19:10:58.915 21554-21554/com.example.fatma.myapplication I/﹕ appName=com.example.fatma.myapplication, acAppName=eu.chainfire.cfbench 
    02-15 19:10:58.915 21554-21554/com.example.fatma.myapplication I/﹕ 0 
    02-15 19:10:58.917 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Resolving service... 
    02-15 19:10:58.934 21554-21554/com.example.fatma.myapplication I/﹕ appName=com.example.fatma.myapplication, acAppName=com.android.cts.openglperf 
    02-15 19:10:58.934 21554-21554/com.example.fatma.myapplication I/﹕ 0 
    02-15 19:10:58.934 21554-21554/com.example.fatma.myapplication I/﹕ appName=com.example.fatma.myapplication, acAppName=com.android.browser 
    02-15 19:10:58.934 21554-21554/com.example.fatma.myapplication I/﹕ 0 
    02-15 19:10:58.960 21554-21554/com.example.fatma.myapplication I/﹕ [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1 
    02-15 19:10:58.960 21554-21554/com.example.fatma.myapplication I/﹕ [Mali]max_allowed_dequeued_buffers=3 
    02-15 19:10:58.983 21554-21554/com.example.fatma.myapplication D/OpenGLRenderer﹕ Enabling debug mode 0 
    02-15 19:10:59.318 21554-21554/com.example.fatma.myapplication D/OpenGLRenderer﹕ PatchDescription: bitmapWidth=24.00, bitmapWidth=24.00, pixelWidth=480.00, pixelHeight=24.00, width=2, height=2, quadCnt=6, transQuadCnt=3, colorKey=56 
    02-15 19:10:59.318 21554-21554/com.example.fatma.myapplication D/OpenGLRenderer﹕ patch: bitmapWidth=24.00, bitmapHeight=24.00, left=0.00, top=0.00, right=480.00, bottom=24.00, verticesCount=18 
    02-15 19:10:59.726 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service name: NsdChat (3) 
    02-15 19:10:59.726 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Port number: 38911 
    02-15 19:10:59.980 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChat (3)type: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:59.980 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Same machine: NsdChat (3) 
    02-15 19:10:59.980 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Service discovery success: name: NsdChat (3)type: _http._tcp.host: nullport: 0txtRecord: null 
    02-15 19:10:59.980 21554-21591/com.example.fatma.myapplication D/---Networking﹕ Same machine: NsdChat (3) 

Пожалуйста, помогите мне.

Answer 1

Путь для проверки Wi-Fi является:

public boolean isWifiAvailable(Context context){ 

    boolean wifiConnected = false; 

    ConnectivityManager connMgr = 
      (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); 
    NetworkInfo activeInfo = connMgr.getActiveNetworkInfo(); 

    if (activeInfo != null && activeInfo.isConnected()) { 
     wifiConnected = activeInfo.getType() == ConnectivityManager.TYPE_WIFI;    
    } else { 
     wifiConnected = false; 
    } 

    return wifiConnected; 
} 

Вызов этого метода из любого Activity или Service как это:

isWifiAvailable(this) 

где this является Context, и он будет возвращать true или false , Надеюсь, это поможет :)