wifi_receiver.java

mWifiBroadcastReceiver = new BroadcastReceiver()
{
  @Override public void onReceive(Context c, Intent intent)
  {
    try
    {
      // Your code here
    }
    catch (Throwable e)
    {
      Logger.d(TAG, 1, Log.getStackTraceString(e));
    }
  }
};
mContext.registerReceiver(mWifiBroadcastReceiver, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));