从 Socket.IO 线程中更新视图

Question

我想是时候向我的 stackoverbros 提问了。我正在使用 socket.io-client.java https://github.com/nkzawa/socket.io-client.java 使用 socket.io 与我的节点服务器通信。到目前为止，连接工作正常。

这是 onCreate 和变量定义。

    class Text
{
    String username;
    String message;
}

Socket socket;
ListView listView;
ArrayList<Text> texts = new ArrayList<Text>();
String username = "";

@Override
protected void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    listView = (ListView) findViewById(R.id.listView);
    initList();
    activateEnter();
    try {
        startSocket();
    } catch (URISyntaxException e) {
        e.printStackTrace();
    }
}

这是创建套接字的函数。

    private void startSocket() throws URISyntaxException
{
    socket = IO.socket("http://localhost");
    socket.on(Socket.EVENT_CONNECT, new Emitter.Listener() 
    {
      @Override
      public void call(Object... args) 
      {
        socket.emit("adduser", "");
      }
    }).on("chat_msg", new Emitter.Listener() 
    {
      @Override
      public void call(Object... args) 
      {
          JSONObject obj = (JSONObject)args[0];
          try {
            String uname = obj.getString("username");
            String msg = obj.getString("msg");
            updateList(uname, msg);
        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
      }
    }).on("username", new Emitter.Listener() 
    {
          @Override
          public void call(Object... args) 
          {
              JSONObject obj = (JSONObject)args[0];
              try {
                username = obj.getString("username");
            } catch (JSONException e) {
                e.printStackTrace();
            }
          }
    }).on(Socket.EVENT_DISCONNECT, new Emitter.Listener() 
    {
      @Override
      public void call(Object... args) 
      {

      }

    });
    socket.connect();
}

现在，我有一个聊天功能，聊天消息通过我在套接字功能之外创建的自定义适配器进入 ListView，就像这样。

class FancyAdapter extends ArrayAdapter<Text>
{
     FancyAdapter()
     {
         super(MainActivity.this, android.R.layout.simple_list_item_1, texts);
     }

     public View getView(int position, View convertView, ViewGroup parent)
     {
         ViewHolder holder;
         if(convertView == null)
         {
             LayoutInflater inflater = getLayoutInflater();
             convertView = inflater.inflate(R.layout.text, null);
             holder = new ViewHolder(convertView);
             convertView.setTag(holder);
         }
         else
         {
             holder = (ViewHolder) convertView.getTag();
         }
         holder.populateFrom(texts.get(position));
         return(convertView);
     }
}

class ViewHolder
{
     public TextView text_username = null;
     public TextView text_message = null;

     ViewHolder(View row)
     {
         text_username = (TextView) row.findViewById(R.id.text_username);
         text_message = (TextView) row.findViewById(R.id.text_message);
     }
     void populateFrom(Text w)
     {
         text_username.setText(w.username);
         text_message.setText(w.message);
     }
}

FancyAdapter adapter = null;

private void initList()
{
      adapter = new FancyAdapter();
      listView.setAdapter(adapter);
}

private void updateList(String uname, String message)
{
    Text text = new Text();
    text.username = uname;
    text.message = message;
    texts.add(text); 
    adapter.notifyDataSetChanged();
}

现在，当我从套接字调用中调用 updateList(string, string) 时，特别是 "chat_message"，我得到 "ViewRootImpl$CalledFromWrongThreadException Only the original thread that created a view hierarchy can touch its views."

哦，好吧，我尝试将 list/adapter 相关函数和类移动到套接字函数的 EVENT_CONNECT 事件中，但似乎无法定义其中定义的内容对于其他事件，例如 "chat_message"。

所以我不确定该怎么做。

Answer 1

您只能与来自 UI 线程的视图进行交互试试这个：

MyActivity.this.runOnUiThread(new Runnable() {

      @Override
      public void run() {
          updateList(uname, msg);
      }
});

从 Socket.IO 线程中更新视图

Updating View from within a Socket.IO thread

java

sockets

android

websocket

socket.io