怎么用广播接收离线信息？

我是copy过来的代码。帮忙看下，下面的对么    
 那个msgid不用自己设置么，？
 
 
     //初始化环信
      private void initHuanXin() {
          EaseUI.getInstance().init(getApplicationContext());//环信聊天
          EMChat.getInstance().setAppInited();
          
          //注册接收新消息的监听广播
          //只有注册了广播才能接收到新消息，目前离线消息，在线消息都是走接收消息的广播（离线消息目前无法监听，在登录以后，接收消息广播会执行一次拿到所有的离线消息）
          NewMessageBroadcastReceiver msgReceiver = new NewMessageBroadcastReceiver();
          IntentFilter intentFilter = new IntentFilter(EMChatManager.getInstance().getNewMessageBroadcastAction());
          intentFilter.setPriority(3);
          registerReceiver(msgReceiver, intentFilter);
          
          //注册接收ack回执消息的BroadcastReceiver
          EMChatManager.getInstance().getChatOptions().setRequireAck(true);//如果用到已读的回执需要把这个flag设置成true
          IntentFilter ackMessageIntentFilter = new IntentFilter(EMChatManager.getInstance().getAckMessageBroadcastAction());
          ackMessageIntentFilter.setPriority(3);
          registerReceiver(ackMessageReceiver, ackMessageIntentFilter);
         
        
    }
      
      //注册接收ack回执消息的BroadcastReceiver
      private BroadcastReceiver ackMessageReceiver = new BroadcastReceiver() {
          
          @Override
          public void onReceive(Context context, Intent intent) {
              abortBroadcast();
              String msgid = intent.getStringExtra("msgid");
              String from = intent.getStringExtra(openid);
              EMConversation conversation = EMChatManager.getInstance().getConversation(from);
              if (conversation != null) {
                  // 把message设为已读
                  EMMessage msg = conversation.getMessage(msgid);
                  if (msg != null) {
                      msg.isAcked = true;
                  }
              }
              
          }
      };

    //注册接收新消息的监听广播
    private class NewMessageBroadcastReceiver extends BroadcastReceiver {
          @Override
          public void onReceive(Context context, Intent intent) {
              // 注销广播
              abortBroadcast();
       
              // 消息id（每条消息都会生成唯一的一个id，目前是SDK生成）
              String msgId = intent.getStringExtra("msgid");
              //发送方
              String username = intent.getStringExtra(openid);//openid为用户ID
              // 收到这个广播的时候，message已经在db和内存里了，可以通过id获取mesage对象
              EMMessage message = EMChatManager.getInstance().getMessage(msgId);
              EMConversation    conversation = EMChatManager.getInstance().getConversation(username);
              // 如果是群聊消息，获取到group id
              if (message.getChatType() == ChatType.GroupChat) {
                  username = message.getTo();
              }
              if (!username.equals(username)) {
                  // 消息不是发给当前会话，return
                  return;
              }
          }
      }

在applicaiton中注册消息监听: /**
     * 全局事件监听
     * 因为可能会有UI页面先处理到这个消息，所以一般如果UI页面已经处理，这里就不需要再次处理
     * activityList.size() <= 0 意味着所有页面都已经在后台运行，或者已经离开Activity Stack
     */
    protected void registerEventListener() {
        eventListener = new EMEventListener() {
            private BroadcastReceiver broadCastReceiver = null;
           
            @Override
            public void onEvent(EMNotifierEvent event) {
                EMMessage message = null;
                if(event.getData() instanceof EMMessage){
                    message = (EMMessage)event.getData();
                    EMLog.d(TAG, "receive the event : " + event.getEvent() + ",id : " + message.getMsgId());
                }
               
                switch (event.getEvent()) {
                case EventNewMessage:
                    //应用在后台，不需要刷新UI,通知栏提示新消息
                    if(!easeUI.hasForegroundActivies()){
                        getNotifier().onNewMsg(message);
                    }
                    break;
                case EventOfflineMessage:
                    if(!easeUI.hasForegroundActivies()){
                        EMLog.d(TAG, "received offline messages");
                        List<EMMessage> messages = (List<EMMessage>) event.getData();
                        getNotifier().onNewMesg(messages);
                    }
                    break;
                // below is just giving a example to show a cmd toast, the app should not follow this
                // so be careful of this
                case EventNewCMDMessage:
                {
                   
                    EMLog.d(TAG, "收到透传消息");
                    //获取消息body
                    CmdMessageBody cmdMsgBody = (CmdMessageBody) message.getBody();
                    final String action = cmdMsgBody.action;//获取自定义action
                   
                    //获取扩展属性 此处省略
                    //message.getStringAttribute("");
                    EMLog.d(TAG, String.format("透传消息：action:%s,message:%s", action,message.toString()));
                    final String str = appContext.getString(R.string.receive_the_passthrough);
                   
                    final String CMD_TOAST_BROADCAST = "easemob.demo.cmd.toast";
                    IntentFilter cmdFilter = new IntentFilter(CMD_TOAST_BROADCAST);
                   
                    if(broadCastReceiver == null){
                        broadCastReceiver = new BroadcastReceiver(){

                            @Override
                            public void onReceive(Context context, Intent intent) {
                                // TODO Auto-generated method stub
                                Toast.makeText(appContext, intent.getStringExtra("cmd_value"), Toast.LENGTH_SHORT).show();
                            }
                        };
                       
                      //注册广播接收者
                        appContext.registerReceiver(broadCastReceiver,cmdFilter);
                    }

                    Intent broadcastIntent = new Intent(CMD_TOAST_BROADCAST);
                    broadcastIntent.putExtra("cmd_value", str+action);
                    appContext.sendBroadcast(broadcastIntent, null);
                   
                    break;
                }
                case EventDeliveryAck:
                    message.setDelivered(true);
                    break;
                case EventReadAck:
                    message.setAcked(true);
                    break;
                // add other events in case you are interested in
                default:
                    break;
                }
               
            }
        };
       
        EMChatManager.getInstance().registerEventListener(eventListener);
    }
 

不管用。。