Twilio Android：加入频道时出现问题：“会员已存在”

Question

我在 android 中使用 Twilio 可编程聊天 API 进行一对一聊天。

以下是我的用例：

1) I create a unique channel name
2) Check if the channel already exists or not
   if channel exists:
     user joins channel
   else
     create a channel with unique name
     user joins channel
   end

现在，正在发生的事情是，当我尝试加入频道时，它给了我错误：“会员已经存在”。因此，此时如果我尝试检查频道的成员，我会得到 Member 对象为空。 在这一点上我有两个疑问：

1) 如果用户对象已经是频道的一部分，它不应该包含这个成员吗？ 2）如果用户已经是频道的一部分，我应该能够通过添加 channelListener 向频道发送消息，在这种情况下不会发生。

我不明白这个问题。以下是我的代码 sn-ps：

ChatClient.Properties props = new ChatClient.Properties.Builder()
            .createProperties();
ChatClient.create(ChatActivity.this, accessToken, props, mChatClientCallback);

private CallbackListener<ChatClient> mChatClientCallback =
    new CallbackListener<ChatClient>() {
        @Override
        public void onSuccess(ChatClient chatClient) {
            mChatClient = chatClient;
            //loadChannels();
            Log.i(TAG, "Success creating Twilio Chat Client");
            createOrJoinChannel();
        }

        @Override
        public void onError(ErrorInfo errorInfo) {
            Log.i(TAG,"Error creating Twilio Chat Client: " + errorInfo.getMessage());
        }
    };


 private void createOrJoinChannel(){
    //Only SID or unique name of channel can be supplied as parameter
      mChatClient.getChannels().getChannel(UNIQUE_CHANNEL_NAME, new CallbackListener<Channel>() {
        @Override
        public void onSuccess(Channel channel) {
            if (channel != null) {
                joinChannel(channel);
            } else {
                Log.i(TAG, "Error occurred in getting channel");
            }
        }

        @Override
        public void onError(ErrorInfo errorInfo) {
            Log.i(TAG,"Error retrieving channel: " + errorInfo.getMessage());
            createChannel();
        }
    });
}

 private void joinChannel(final Channel channel) {
    Log.i(TAG, "inside join channel" + channel.getUniqueName());
    Log.i(TAG, "channel status: " + channel.getStatus());

    Members members = channel.getMembers();
    if(members!=null){
        ArrayList<Member> list = (ArrayList<Member>) members.getMembersList();
        for(int i=0; i<list.size(); i++){
            Log.i(TAG, "member " + i + list.get(i).getIdentity());
        }
    }else{
        Log.i(TAG, "null object"); //Getting this even when I get 
                                   //"Member already exists" error
    }

    channel.join(new StatusListener() {
        @Override
        public void onSuccess() {
            mGeneralChannel = channel;
            mGeneralChannel.addListener(mDefaultChannelListener);
        }

        @Override
        public void onError(ErrorInfo errorInfo) {
            //Error joining channel: Member already exists
            Log.i(TAG,"Error joining channel: " + errorInfo.getMessage());
    });
}

 private void createChannel(){
    mChatClient.getChannels().createChannel(FRIENDLY_CHANNEL_NAME,
        Channel.ChannelType.PUBLIC, new CallbackListener<Channel>() {
            @Override
            public void onSuccess(Channel channel) {
                if (channel != null) {
                   setUniqueNameAndJoin(channel);
                }
            }

            @Override
            public void onError(ErrorInfo errorInfo) {
                Log.i(TAG,"chats: " + "Unique name could not be set: " + errorInfo.getMessage());
            }
        });
 }

 private void setUniqueNameAndJoin(final Channel channel){
    channel.setUniqueName(UNIQUE_CHANNEL_NAME, new StatusListener() {
        @Override
        public void onSuccess() {
            Log.i(TAG, "channel with unique name created " + channel.getUniqueName());
            joinChannel(channel);
        }

        @Override
        public void onError(ErrorInfo errorInfo) {
            super.onError(errorInfo);
        }
    });

}


private ChannelListener mDefaultChannelListener = new ChannelListener() {
    @Override
    public void onMessageAdded(final Message message) {
        Log.i(TAG, "Message added");
        ChatActivity.this.runOnUiThread(new Runnable() {
            @Override
            public void run() {
                // need to modify user interface elements on the UI thread
                mMessages.add(message);
                mMessagesAdapter.notifyItemInserted(mMessages.size()-1);
            }
        });
    }

    @Override
    public void onMessageUpdated(Message message, Message.UpdateReason updateReason) {
        Log.i(TAG, "Message updated: " + message.getMessageBody());
    }

    @Override
    public void onMessageDeleted(Message message) {
        Log.d(TAG, "Message deleted");
    }

    @Override
    public void onMemberAdded(Member member) {
        Log.i(TAG, "Member added: " + member.getIdentity());
    }

    @Override
    public void onMemberUpdated(Member member, Member.UpdateReason updateReason) {
    }

    @Override
    public void onMemberDeleted(Member member) {

    }

    @Override
    public void onTypingStarted(Channel channel, Member member) {

    }

    @Override
    public void onTypingEnded(Channel channel, Member member) {

    }

    @Override
    public void onSynchronizationChanged(Channel channel) {

    }
};

有人可以向我解释一下，我做错了什么或者应该是正确的做事方式吗？提前致谢！

Answer 1

这里是 Twilio 开发者宣传员。

您需要使用channel.getStatus() 检查当前用户的频道状态。 Android chat tutorial 中有一个很好的例子。

if (this.currentChannel.getStatus() == Channel.ChannelStatus.JOINED) {
    // already in the channel, load the messages
} else {
    // join the channel
}