Question

开发聊天应用程序。我使用smack库完成了它们。一切正常，即使用户也可以互相聊天，但无法将传入的消息设置到ListView的右侧。我已经尝试了TextView对权利的严重性。但我无法实现它。我提到了一些这些问题，但我没有帮助过我！

public class ChatRoom extends Activity {
    private final static String SERVER_HOST = "talk.google.com";
    private final static int SERVER_PORT = 5222;
    private final static String SERVICE_NAME = "gmail.com";
    private final static String LOGIN = "acd@gmail.com";
    private final static String PASSWORD = "password";
    private List<String> m_discussionThread;
    private XMPPConnection m_connection;
    private Handler m_handler;
    private String mtemp_user_id;
    private ProgressDialog p_dialog;
    EditText mMsg;
    ListView listview;
    MyAdapter myadpter;
    String fromName;
    String mtempSpecial;
    String SendMSg, RecievdMsg;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_chat_screen);
        PrepareChat prechat = new PrepareChat(); //AsyncTask
        m_handler = new Handler();
        p_dialog = new ProgressDialog(ChatRoom.this);
        m_discussionThread = new ArrayList<String>();
        myadpter = new MyAdapter(m_discussionThread);
        Bundle bundle = getIntent().getExtras();
        mtemp_user_id = bundle.getString("USER");

        prechat.execute();


        listview = (ListView) findViewById(R.id.list_view_);
        listview.setAdapter(myadpter);

        mMsg = (EditText) findViewById(R.id.ed_msg);
        findViewById(R.id.b_MSG_To).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                SendMSg = "SEND";
                Message msg = new Message(mtemp_user_id, Message.Type.chat);
                msg.setBody(mMsg.getText().toString());
                m_connection.sendPacket(msg);
                m_discussionThread.add(mMsg.getText().toString());
                mMsg.setText("");
            }
        });
    }

    public class PrepareChat extends AsyncTask<Void, Void, Void> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            p_dialog.setMessage("Preparing chat");
            p_dialog.setCancelable(false);
            p_dialog.show();
        }

        @Override
        protected Void doInBackground(Void... params) {
            System.out.println("In do in back ...");
            try {
                initConnection();
            } catch (XMPPException e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            super.onPostExecute(result);
            p_dialog.dismiss();
        }
    }

    private void initConnection() throws XMPPException {
        ConnectionConfiguration config = new ConnectionConfiguration(
                SERVER_HOST, SERVER_PORT, SERVICE_NAME);
        m_connection = new XMPPConnection(config);
        m_connection.connect();

        m_connection.login(LOGIN, PASSWORD);
        System.out.println("After LOGInd");
        Presence presence = new Presence(Presence.Type.available);
        presence.setStatus("available");
        m_connection.sendPacket(presence);
        PacketFilter filter = new MessageTypeFilter(Message.Type.chat);
        m_connection.addPacketListener(new PacketListener() {
            public void processPacket(Packet packet) {
                Message message = (Message) packet;

                if (message.getBody() != null) {
                    String fromName = StringUtils.parseBareAddress(message
                            .getFrom());

                    String mtempSpecial = message.getBody().toString();
                    m_discussionThread.add(mtemp_user_id + mtempSpecial);
                    RecievdMsg = "RE";
                    m_handler.post(new Runnable() {
                        public void run() {

                            myadpter.notifyDataSetChanged();
                            listview.setSelection(myadpter.getCount() - 1);
                        }
                    });
                }
            }
        }, filter);
    }

    public class MyAdapter extends BaseAdapter {
        LayoutInflater layoutinflate;
        List<String> list = new ArrayList<String>();
        Context context;

        public MyAdapter(List<String> m_discussionThread) {
            list = m_discussionThread;
        }

        @Override
        public int getCount() {
            return list.size();
        }

        @Override
        public Object getItem(int items) {
            return items;
        }

        @Override
        public long getItemId(int posi) {
            return posi;
        }

        @Override
        public View getView(int position, View arg1, ViewGroup view_Group) {
            View view_ = arg1;
            LayoutInflater layout_inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            if (SendMSg.equals("SEND")) {
                view_ = layout_inflater.inflate(R.layout.chat_b, view_Group,
                        false);
                TextView tv_MyMsg = (TextView) view_
                        .findViewById(R.id.tv_mymsg);
                System.out.println("in send loop");
            //  tv_MyMsg.setGravity(Gravity.RIGHT);
                tv_MyMsg.setText(list.get(position)); //TextView not binding to the right.
                SendMSg = "";
            } else {
                view_ = layout_inflater.inflate(R.layout.chat_ab, view_Group,
                        false);
                TextView tv_FromMsg = (TextView) view_
                        .findViewById(R.id.tv_From_Msg);
                tv_FromMsg.setText(list.get(position)); 
                /*
                 * tv_ToMsg.setGravity(Gravity.LEFT);
                 * System.out.println("in else"); tv_FromMsg.setText("");
                 * tv_ToMsg.setText(list.get(position));
                 */}


            return view_;
        }

    }

}

更新

仅填充chat_ab.xml，但忽略包含绿色文本的chat_b.xml。

chat_ab.xml ...

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:background="#ffffff"
android:layout_gravity="left"
android:layout_height="fill_parent" >

 <TextView
    android:id="@+id/tv_From_Msg"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:gravity="left"
    android:text="Large Text"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:textColor="#FF00FF" />

chat_b.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:background="#ffffff"
android:layout_gravity="right"
android:layout_height="fill_parent" >

<TextView
    android:id="@+id/tv_mymsg"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textColor="#0000ff"
    android:layout_alignParentRight="true"
    android:gravity="right"
    android:layout_alignParentTop="true"
    android:text="Large Text"
    android:textAppearance="?android:attr/textAppearanceLarge" />

到目前为止我得到的是 Up screen shot 我期待的是我的消息（走出去）ListView的右侧并且向屏幕左侧传出。请建议。

Answer 1

您可以使用LinearLayout中的android:gravity和android:layout_gravity属性来实现此目的。

请参阅Android Listview for chat application.

Answer 2

对列表视图内的textview使用不同的布局。每次列表视图填充新条目（消息）时，请使用user.getEmail（）将当前用户的Auth与发送者的Auth进行比较。如果它们匹配，则将上述textview的布局重力设置为右，否则为左。

在android中使用自定义列表视图时无法设置左右对话

2 个答案: