smack presence listener in multi user chat

问题

smack presence listener in multi user chat not getting called. Used Smack Api to login and then added roster.addRosterListener(mRoasterListener); but could not get any success to listen when presence of other user of the chat room changes. I tried following code to get the presence listener to work :

connection.login(loginUser, passwordUser);

MultiUserChatManager manager = 

MultiUserChatManager.getInstanceFor(connection);

muc = manager.getMultiUserChat(roomID + "@" +context.getString(R.string.group_chat_id));

Log.d("Join User: ", "Already Created");

muc.join(Utilities.getUserPhoneNo(context));

muc.addMessageListener(mGroupMessageListener);

Roster roster = Roster.getInstanceFor(connection);//luna

roster.addRosterListener(mRoasterListener);//roasterListener

Log.d("Joined User Phone: ", " " + Utilities.getUserPhoneNo(context));

and this class to listen for presence change...

public class RoasterListener implements RosterListener{
        public RoasterListener(Context context){

        }

        @Override
        public void entriesAdded(Collection<String> collection) {

        }

        @Override
        public void entriesUpdated(Collection<String> collection) {

        }

        @Override
        public void entriesDeleted(Collection<String> collection) {

        }

        @Override
        public void presenceChanged(Presence presence) {
            System.out.println("Presence changed: " + presence.getFrom() + " " + presence);
        }
    }

I tried many links available by stackoverflow but could not get any success. Please Help!

回答1:

For Multi User Chat you don't have to use Roster, because it's normal to meet people you don't have in Roster.

To know who is in a muc, first ask for occupants:

muc.join(user,password);

List<String> occupantsAtJoinTime = muc.getOccupants();

                    for (String occupant : occupantsAtJoinTime)
                    {
                        System.out.println("occupant: "+occupant);
                        //actions
                    }

then, to keep Occupants list updated, register a DefaultParticipantStatusListener to your muc and define that Listner:

muc.addParticipantStatusListener(new CustomParticipantStatusListner());

definied as (there are many methods to implement if you need):

    public class CustomParticipantStatusListner extends DefaultParticipantStatusListener 
    {

        public void joined(String participant) 
        {
            System.out.println(participant + "just joined MUC");
//actions (add occupantsRightNow)
        }

        public void left(String participant)
        {
            System.out.println(participant + " just left MUC");
//actions (remove occupantsRightNow)
        }
    }

All this with smack 4.1.7

回答2:

It's about the Manage role modifications in Multi User Chat. This example shows how to grant voice to a visitor and listen for the notification events:

// User1 creates a room
  muc = new MultiUserChat(conn1, "myroom@conference.jabber.org");
  muc.create("testbot");

  // User1 (which is the room owner) configures the room as a moderated room
  Form form = muc.getConfigurationForm();
  Form answerForm = form.createAnswerForm();
  answerForm.setAnswer("muc#roomconfig_moderatedroom", "1");
  muc.sendConfigurationForm(answerForm);

  // User2 joins the new room (as a visitor)
  MultiUserChat muc2 = new MultiUserChat(conn2, "myroom@conference.jabber.org");
  muc2.join("testbot2");
  // User2 will listen for his own "voice" notification events
  muc2.addUserStatusListener(new DefaultUserStatusListener() {
      public void voiceGranted() {
          super.voiceGranted();
          ...
      }
      public void voiceRevoked() {
          super.voiceRevoked();
          ...
      }
  });

  // User3 joins the new room (as a visitor)
  MultiUserChat muc3 = new MultiUserChat(conn3, "myroom@conference.jabber.org");
  muc3.join("testbot3");
  // User3 will lister for other occupants "voice" notification events
  muc3.addParticipantStatusListener(new DefaultParticipantStatusListener() {
      public void voiceGranted(String participant) {
          super.voiceGranted(participant);
          ...
      }

      public void voiceRevoked(String participant) {
          super.voiceRevoked(participant);
          ...
      }
  });

  // The room's owner grants voice to user2
  muc.grantVoice("testbot2"); 

Details can be refered in http://web.mit.edu/svalente/lib/smack_3_0_4/documentation/extensions/muc.html .

回答3:

Firstly, join a chat room:

public MultiUserChat joinMultiUserChat(String user, String roomsName,
        String password) {
    if (getConnection() == null)
        return null;
    try {
        MultiUserChat muc = new MultiUserChat(getConnection(), roomsName
                + "@conference." + getConnection().getServiceName());
        DiscussionHistory history = new DiscussionHistory();
        history.setMaxChars(0);
        // history.setSince(new Date());
        muc.join(user, password, history,
                SmackConfiguration.getPacketReplyTimeout());
        Log.i("MultiUserChat", "Chat room【"+roomsName+"】joined........");
        return muc;
    } catch (XMPPException e) {
        e.printStackTrace();
        Log.i("MultiUserChat", "Chat room【"+roomsName+"】failed........");
        return null;
    }
}

Then, use MultiChatUser to send Message:

try {
    multiUserChat.sendMessage(message);
} catch (XMPPException e) {
    e.printStackTrace();
}

Add a Listener:

import org.jivesoftware.smack.PacketListener;
import org.jivesoftware.smack.packet.Message;
import org.jivesoftware.smack.packet.Packet;

public class TaxiMultiListener implements PacketListener {
    @Override
    public void processPacket(Packet packet) {
        Message message = (Message) packet;
        String body = message.getBody();
    }
}

Finally, call the Listener using MultiUserChat:

multiUserChat.addMessageListener(new TaxiMultiListener());

来源：https://stackoverflow.com/questions/37524493/smack-presence-listener-in-multi-user-chat