如何处理wifi和移动数据之间的网络变化？

3 回答

• 0

  你正在寻找的答案是 BroadcastReceiver . 检查以下链接 .

  BroadcastReceiver when wifi or 3g network state changed

  希望它能帮助您解决问题，如果是，请考虑结束您的问题 .

  回复于 2024-05-13T19:45:25+08:00
• 11

  您可以使用ConnectivityManager的API：特别是在您感兴趣的registerDefaultNetworkCallback()用例中：

  public class TestActivity extends AppCompatActivity {
  
          private ConnectivityManager manager;
          private final ConnectivityManager.NetworkCallback networkCallback = new ConnectivityManager.NetworkCallback() {
              @Override
              public void onAvailable(Network network) {
                  super.onAvailable(network);
                  // this ternary operation is not quite true, because non-metered doesn't yet mean, that it's wifi
                  // nevertheless, for simplicity let's assume that's true
                  Log.i("vvv", "connected to " + (manager.isActiveNetworkMetered() ? "LTE" : "WIFI"));
              }
  
              @Override
              public void onLost(Network network) {
                  super.onLost(network);
                  Log.i("vvv", "losing active connection");
              }
          };
  
          @Override
          protected void onCreate(@Nullable Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
  
              manager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
              manager.registerDefaultNetworkCallback(networkCallback);
          }
  
          @Override
          protected void onDestroy() {
              super.onDestroy();
              manager.unregisterNetworkCallback(networkCallback);
          }
      }
  

  我的设备在大约半秒内连接到LTE .

  

  这意味着，当WIFI断开连接时，您无法事先知道设备最终是否会连接到LTE或者没有连接到LTE . 因此，您可以采用以下方法：在一秒钟内对处理程序发布操作，并在此操作中取消调用 . 如果很快就会出现连接 - 取消预先安排以前发布的操作 . 如果您最终处于 Runnable 代码中，则表示连接未快速 Build ，这意味着您应该结束通话 .

  public class TestActivity extends AppCompatActivity {
  
          private ConnectivityManager manager;
  
          private final Handler handler = new Handler();
          private final ConnectivityManager.NetworkCallback networkCallback = new ConnectivityManager.NetworkCallback() {
              @Override
              public void onAvailable(Network network) {
                  super.onAvailable(network);
                  Log.i("vvv", "connected to " + (manager.isActiveNetworkMetered() ? "LTE" : "WIFI"));
  
                  // we've got a connection, remove callbacks (if we have posted any)
                  handler.removeCallbacks(endCall);
              }
  
              @Override
              public void onLost(Network network) {
                  super.onLost(network);
                  Log.i("vvv", "losing active connection");
  
                  // Schedule an event to take place in a second
                  handler.postDelayed(endCall, 1000);
              }
          };
  
          private final Runnable endCall = new Runnable() {
              @Override
              public void run() {
                  // if execution has reached here - feel free to cancel the call
                  // because no connection was established in a second
              }
          };
  
          @Override
          protected void onCreate(@Nullable Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
  
              manager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
              manager.registerDefaultNetworkCallback(networkCallback);
          }
  
          @Override
          protected void onDestroy() {
              super.onDestroy();
              manager.unregisterNetworkCallback(networkCallback);
              handler.removeCallbacks(endCall);
          }
      }
  

  该方法的缺点是，registerDefaultNetworkCallback()从API 24开始可用 . 在ConnectivityManagerCompat中也没有替代方案 . 相反，您可以使用API 21中提供的registerNetworkCallback() .

  回复于 2024-05-13T19:45:25+08:00
• 2

  您可以使用 BroadcastReceiver 并注册 NETWORK_STATE_CHANGED_ACTION ＆ WIFI_STATE_CHANGED_ACTION .

  private boolean isConnected;
  
  final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
      @Override
      public void onReceive(Context context, Intent intent) {
          if (intent == null || intent.getAction() == null)
              return;
          switch (intent.getAction()){
              case WifiManager.NETWORK_STATE_CHANGED_ACTION :
              case WifiManager.WIFI_STATE_CHANGED_ACTION :
                  if (!isConnected && isOnline(BaseActivity.this)) {
                      isConnected = true;
                      // do stuff when connected
                      Log.i("Network status: ","Connected");
                  }else{
                      isConnected = isOnline(BaseActivity.this);
                      Log.i("Network status: ","Disconnected");
                  }
                  break;
          }
      }
  };
  
  
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      isConnected = isOnline(this);
      final IntentFilter filters = new IntentFilter();
      filters.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION);
      filters.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
      registerReceiver(broadcastReceiver, filters);
  }
  
  
  public static boolean isOnline(Context ctx) {
      ConnectivityManager cm = (ConnectivityManager) ctx
              .getSystemService(Context.CONNECTIVITY_SERVICE);
      NetworkInfo netInfo = cm != null
              ? cm.getActiveNetworkInfo()
              : null;
      return netInfo != null && netInfo.isConnectedOrConnecting();
  }
  

  Update 别忘了取消注册收件人 BroadcastReceiver onDestroy

  @Override
  protected void onDestroy() {
      unregisterReceiver(broadcastReceiver);
      super.onDestroy();
  }
  

  回复于 2024-05-13T19:45:25+08:00