aSmack即服务

Question

基本上，我有一个运行整个项目的主类。代码运行得很好，不过一旦应用程序没有被关注，它就会变得不活跃。我在想我该怎么做才能把它变成一种服务。一个可以在开机时启动的程序。

该应用程序将是一个单向的通知消息系统。也就是说。

桌面客户端-> Openfire服务器-> Android XMPP服务->存储(DB) ->用于显示的Android图形用户界面

正如我所说的，代码是工作的(连接，登录，接收)，但不是一个服务。

我可以使用BEEM源代码，但它太过特色和交错。我想要一个轻量级的服务。

代码：

public class MainActivity extends Activity {

  public static final String HOST = "fire.example.com";
  public static final int PORT = 5222;
  public static final String SERVICE = "example.com";
  public static final String USERNAME = "metest@fire.example.com";
  public static final String PASSWORD = "mepass";

  private XMPPConnection connection;
  private ArrayList<String> messages = new ArrayList<String>();
  private Handler mHandler = new Handler();
  private ListView listview;
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    listview = (ListView) this.findViewById(R.id.listMessages);
    setListAdapter();

    connect();
  }

  /**
   * Called by Settings dialog when a connection is establised with 
   * the XMPP server
   */
  public void setConnection(XMPPConnection connection) {
    this.connection = connection;
    if (connection != null) {
      // Add a packet listener to get messages sent to us
      PacketFilter filter = new MessageTypeFilter(Message.Type.chat);
      connection.addPacketListener(new PacketListener() {
        @Override
        public void processPacket(Packet packet) {
          Message message = (Message) packet;
          if (message.getBody() != null) {
            String fromName = StringUtils.parseBareAddress(message.getFrom());
            Log.i("XMPPChatActivity ", " Text Recieved " + message.getBody() + " from " +  fromName);

            messages.add(message.getBody());


            mHandler.post(new Runnable() {
              public void run() {
                setListAdapter();
              }
            });
          }
        }


      }, filter);
    }
  }
  @TargetApi(Build.VERSION_CODES.HONEYCOMB)
@SuppressLint("NewApi")


  private void setListAdapter() {
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.listitem, messages);
    listview.setAdapter(adapter);
  }

  @Override
  protected void onDestroy() {
    super.onDestroy();
    try {
      connection.disconnect();
    } catch (Exception e) {

    }
  }

  public void connect() {

    final ProgressDialog dialog = ProgressDialog.show(this, "Connecting...", "Please wait...", false);
    Thread t = new Thread(new Runnable() {
      @Override
      public void run() {
        // Create a connection
       ConnectionConfiguration connConfig = new ConnectionConfiguration(HOST, PORT, SERVICE);
       XMPPConnection connection = new XMPPConnection(connConfig);
         try {
           connection.connect();
           Log.i("XMPPChatActivity",  "[SettingsDialog] Connected to "+connection.getHost());
         } catch (XMPPException ex) {
             Log.e("XMPPChatActivity",  "[SettingsDialog] Failed to connect to "+ connection.getHost());
             Log.e("XMPPChatActivity", ex.toString());
             setConnection(null);
         }
          try {
            connection.login(USERNAME, PASSWORD);
            Log.i("XMPPChatActivity",  "Logged in as" + connection.getUser());

            // Set the status to available
            Presence presence = new Presence(Presence.Type.available);
            connection.sendPacket(presence);
            setConnection(connection);

            Roster roster = connection.getRoster();
            Collection<RosterEntry> entries = roster.getEntries();
            for (RosterEntry entry : entries) {

              Log.d("XMPPChatActivity",  "--------------------------------------");
              Log.d("XMPPChatActivity", "RosterEntry " + entry);
              Log.d("XMPPChatActivity", "User: " + entry.getUser());
              Log.d("XMPPChatActivity", "Name: " + entry.getName());
              Log.d("XMPPChatActivity", "Status: " + entry.getStatus());
              Log.d("XMPPChatActivity", "Type: " + entry.getType());
              Presence entryPresence = roster.getPresence(entry.getUser());

              Log.d("XMPPChatActivity", "Presence Status: "+ entryPresence.getStatus());
              Log.d("XMPPChatActivity", "Presence Type: " + entryPresence.getType());

              Presence.Type type = entryPresence.getType();
              if (type == Presence.Type.available)
                Log.d("XMPPChatActivity", "Presence AVIALABLE");
                Log.d("XMPPChatActivity", "Presence : " + entryPresence);
              }
              } catch (XMPPException ex) {
                Log.e("XMPPChatActivity", "Failed to log in as "+  USERNAME);
                Log.e("XMPPChatActivity", ex.toString());
                setConnection(null);
              }
              dialog.dismiss();
           }
      });
    t.start();
    dialog.show();
  }
}

因此，基本上，我如何使这成为一项服务

Answer 1

我猜这个例子在给定的链接上会给你一个想法，让它成为一种服务。http://android.codeandmagic.org/small-test-of-asmack-xmpp-client-library/

Answer 2

你需要使用Android Service Framework.

你可以查看GTalk SMS的源代码，因为他们利用了一项服务，并且是开源的。(Main Service是它们用来处理连接等的服务)虽然它也很复杂。

我强烈建议你检查一下在Android中使用服务的基础知识。

请记住，服务不会创建新的线程，所有的工作都是在UI线程上完成的，所以如果你想在后台执行长时间运行的任务，那么你还需要实现一个异步任务或executor服务。

Answer 3

这是个老问题，但我还是会回答的。

您需要创建一个服务，启动它，并将您的aSmack连接代码放在服务中，而不是放在任何活动中。即使应用程序不在前台，该服务也会保持连接。我在我的一个客户的应用程序中使用了这种方法，它工作得很好。

此外，请确保在服务中使用处理程序或AsyncTask在另一个非UI线程中创建套接字连接。Android无论如何都不允许你在UI线程中创建连接。