Question

Hi i am having a strange trouble, i am not gettings bubble for example you messeges on right and mine on left… when ever i call notifydatachanges it erases all the bubbles…plz guide me. below is the code…

private final Handler mHandler = new Handler() {
    @Override
    public void handleMessage(Message msg) {

        if(D) Log.d(TAG, "In the Handler");
        switch (msg.what) {
            case PACKET_CAME:
                String incomingMessage = (String) msg.obj;
                receivedMessages.add("You: " + incomingMessage);

                mg = new Message();
                mg.what = 1;
                updateListHandler.sendMessage(mg);

       //         mAdapter.notifyDataSetChanged();

       //       mAdapter.notifyDataSetInvalidated();

                break;
            case TOAST:
                String toastToMake= (String) msg.obj;
                Toast.makeText(getApplicationContext(), toastToMake,    Toast.LENGTH_SHORT).show();
                break;               
        }
      }
    };   

/** Called when the activity is first created. */
     @Override
    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    send    = (Button)findViewById(R.id.send);
    send.setOnClickListener(send_listener);

    //msgList.setTextFilterEnabled(true);


    msg     = (EditText)findViewById(R.id.msg);
    msg.setOnKeyListener(new OnKeyListener() {
        public boolean onKey(View v, int keyCode, KeyEvent event) {
            // If the event is a key-up event on the "enter" button
            if ((event.getAction() == KeyEvent.ACTION_UP) &&
                    (keyCode == KeyEvent.KEYCODE_ENTER)) {
                postMessage();
                return true;
            }
            return false;
        }
    });

    // Start my server thread
    myThread = new ServerThread(getApplicationContext(),mHandler);

    //Check if it's running
    if (!myThread.socketIsOK()){
       Log.e(TAG,"Server NOT STARTED");
       Toast.makeText(getApplicationContext(), "Cannot Start Server: ", Toast.LENGTH_LONG).show();
       return;
     }

       // All appears to be OK, start the main loop
       myThread.start();
       Log.i(TAG,"Server Started");


     msgList = (ListView)findViewById(R.id.msgList);
     mAdapter = new CustomAdapter();
     msgList.setAdapter(mAdapter);


    }// end OnCreate()

   public class CustomAdapter extends BaseAdapter {
    public CustomAdapter(){
    // TODO Auto-generated constructor stub
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {         

            LayoutInflater inflater = getLayoutInflater();
            View row = null;
            Log.i("sentmsg", Integer.toString(sentmsg));
            Log.i("revmsg", Integer.toString(recvmsg));

            if(sentmsg == 1){
                row = inflater.inflate(R.layout.message, parent, false);
                TextView tv =   (TextView)row.findViewById(R.id.textmsg);       
                tv.setText(receivedMessages.get(position));                 
                sentmsg = 0;
            }else{
                row = inflater.inflate(R.layout.messagert, parent, false);
                TextView tv = (TextView)row.findViewById(R.id.textmsg);     
                tv.setText(receivedMessages.get(position));                 
            }


            return row;
        }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return receivedMessages.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }
    }


  // Sends the message in the msg EditText
   private void postMessage(){
    String theNewMessage = msg.getText().toString();

    try{
        myThread.sendMessage(theNewMessage);
    }catch(Exception e){
        Log.e(TAG,"Cannot send message"+e.getMessage());
    }
    sentmsg = 1;
    receivedMessages.add("Me: " + theNewMessage);

    Message msg = new Message();
    msg.what = 1;
    updateListHandler.sendMessage(msg);

  //    msgList.invalidateViews();
  //  mAdapter.notifyDataSetChanged();
  //  mAdapter.notifyDataSetInvalidated();
  //  msgList.invalidateViews();
  }

  private Handler updateListHandler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
        switch (msg.what) {
        case 1:
            mAdapter.notifyDataSetChanged();
            break;
        }
        ;
    };
   };





  // On click listener for the button
  private OnClickListener send_listener = new OnClickListener() {
    public void onClick(View v) {
        postMessage();
    }
  };

  @Override
  public void onDestroy(){
    super.onDestroy();
    myThread.closeSocket();
  }

   }// Activity class

This is the xml

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/textmsg"
android:layout_marginTop="2px"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="10dp"
android:textSize="16sp" 
android:background="@drawable/greybox">
 </TextView>
</LinearLayout>

this is another xml

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/textmsg"
 android:layout_marginTop="2px"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:padding="10dp"
 android:textSize="16sp">
 </TextView>  
 </LinearLayout>

greybox is 9 patch image.
The sentmsg acts like a flag so that i can inflate the required row according to message recevied or sent…

Answer 1

You have not organised your chat data properly. Have a class that holds a chat message and its sender id.

class Message {
   int senderId;
   String message;
}

Use this object to create the list of chat messages. Then in adapter’s getview method do this

Message msg = messageList.get(position);
if (msg.getSenderId() == getMyId()) { // if its the message sent by me?
    // inflate right side layout.
else 
    // inflate left side layout.