您好，我对在 Service 中实现 chatManagerListener 接口(interface)的逻辑感到困惑。 以下是我的服务代码:

public class MyService3 extends Service {
ChatManager chatManager;
ChatManagerListener chatManagerListener;
AbstractXMPPConnection abstractXMPPConnection;
MyXmpp2 myXmpp2;

public MyService3() {
}


@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    Log.d("Myservice3:","Started");

    abstractXMPPConnection = myXmpp2.getConnection();
    abstractXMPPConnection.addConnectionListener(new ConnectionListener() {
        @Override
        public void connected(XMPPConnection connection) {
            Log.d("XMPPConnection:","connected");
        }

        @Override
        public void authenticated(XMPPConnection connection, boolean resumed) {
            Log.d("XMPPConnection:","authenticated");
            //Once authenticated start listening for messages






        }

        @Override
        public void connectionClosed() {
            Log.d("XMPPConnection:","connectionClosed");
        }

        @Override
        public void connectionClosedOnError(Exception e) {
            Log.d("XMPPConnection:","connectionClosedOnError");
        }

        @Override
        public void reconnectionSuccessful() {
            Log.d("XMPPConnection:","reconnectionSuccessful");

        }

        @Override
        public void reconnectingIn(int seconds) {
            Log.d("XMPPConnection:","reconnectingIn");

        }

        @Override
        public void reconnectionFailed(Exception e) {
            Log.d("XMPPConnection:","reconnectionFailed");

        }
    });



    Log.d("isOnline:", myXmpp2.getConnection().isConnected() + "");
    chatManager = ChatManager.getInstanceFor(abstractXMPPConnection);
    chatManager.addChatListener(chatManagerListener);
    chatManagerListener = new ChatManagerListener() {
        @Override
        public void chatCreated(Chat chat, boolean createdLocally) {

            chat.addMessageListener(new ChatMessageListener() {
                @Override
                public void processMessage(Chat chat, Message message) {

                    Log.d("Hello::","World");
                   //NOT WORKNIG
                    if(message.getBody()!=null)
                    {
                        Log.d("Message::",message.getBody());
                    }
                }
            });
        }
    };





    return super.onStartCommand(intent, flags, startId);
}



}

每当发送一个数据包时，我都会收到以下异常。我不知道它为什么会出现

Exception in packet listener java.lang.NullPointerException: Attempt to invoke interface method 'void org.jivesoftware.smack.chat.ChatManagerListener.chatCreated(org.jivesoftware.smack.chat.Chat, boolean)' on a null object reference
                                                                                       at org.jivesoftware.smack.chat.ChatManager.createChat(ChatManager.java:255)
                                                                                       at org.jivesoftware.smack.chat.ChatManager.createChat(ChatManager.java:287)

简单来说，我想知道如何在服务中实现 ChatMessage 监听器。请客气

最佳答案

成功连接和验证后，您需要创建聊天

一旦你得到了ChatManager的实例。为了包传输你需要createchat 与peer/group check this link用于创建聊天的方法。

 chatManager = ChatManager.getInstanceFor(abstractXMPPConnection);

newChat = chatmanager.createChat(userid, chatManagerListener);  

一旦你得到Chat例如，您可以在 chatmanagerListner

从 newChat 您可以 sendMessage

To get Package (message, chat)

如果您的连接/身份验证过程成功完成，您可以尝试以下代码

final Chat newChat = ChatManager.getInstanceFor(xmppConn).createChat(userJid, new MessageListener() {
    @Override
    public void processMessage(final Chat arg0, final Message arg1) {
      LOG.info("Sent message: " + arg1.getBody());
    }
  });
  try {
    final Message message = new Message();
    message.setFrom(chatProperties.getDomain());
    message.setTo(userJid);
    message.setType(Type.normal);
    message.setBody(text);
    message.setSubject("");
    newChat.sendMessage(message);
    xmppConn.disconnect();
  } catch (final Exception e) {
    LOG.error("Error while sending message to " + userName + ": ", e);
  }

更新

您可以尝试使用 PacketListener .

XMPPConnection 的 addPacketListener 方法 check this link for details .

使用 PacketFilter 将 PacketListener 添加到 XMPPConnection|输入消息

但是在添加 packetlistner 之前，如果已经在 xmppconnection 中添加了任何实例，则删除。

检查下面的代码

private PacketListener packetListener = new PacketListener() {
        @Override
        public void processPacket(Packet packet) {
            if (packet instanceof Message) {
                Message message = (Message) packet;
                String chatMessage = message.getBody();
            }
        }
    };

    private void regiSterPackateListner() {
        PacketTypeFilter filter = new PacketTypeFilter(Message.class);
        try {
            if (packetListener != null) {
                //Avoid adding multiple packetlistner
                abstractXMPPConnection.removePacketListener(packetListener);
            }
            abstractXMPPConnection.addPacketListener(packetListener, filter);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

关于java - 如何在不使用 createChat for android XMPP chat smack api 的情况下接收消息，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35477336/