1.运行效果图
2.核心代码
MainActivity
package cn.bzu.tong.talktest;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
public class MainActivity extends Activity {
private ListView msgListView;
private EditText inputText;
private Button send;
private MsgAdapter adapter;
private List<Msg> msgList = new ArrayList<Msg>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
initMsgs();
adapter = new MsgAdapter(MainActivity.this,R.layout.msg_item,msgList);
inputText = (EditText) findViewById(R.id.input_text);
send = (Button) findViewById(R.id.send);
msgListView = (ListView) findViewById(R.id.msg_list_view);
msgListView.setAdapter(adapter);
send.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View view) {
String content = inputText.getText().toString();
if (!"".equals(content)) {
Msg msg = new Msg(content,Msg.TYPE_SEND);
msgList.add(msg);
adapter.notifyDataSetChanged();
msgListView.setSelection(msgList.size());
inputText.setText("");
}
}
});
}
private void initMsgs(){
Msg msg1 = new Msg("Hello guy.",Msg.TYPE_RECEIVED);
msgList.add(msg1);
Msg msg2 = new Msg("Hello.Who is that?",Msg.TYPE_SEND);
msgList.add(msg2);
Msg msg3 = new Msg("This is Tom.Nice to talking to you",Msg.TYPE_RECEIVED);
msgList.add(msg3);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Msg
package cn.bzu.tong.talktest;
public class Msg {
public static final int TYPE_RECEIVED = 0;
public static final int TYPE_SEND = 1;
private String content;
private int type;
public Msg(String content, int type) {
this.content = content;
this.type = type;
}
public String getContent() {
return content;
}
public int getType() {
return type;
}
}
package cn.bzu.tong.talktest;
import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;
public class MsgAdapter extends ArrayAdapter<Msg> {
private int resourceId;
public MsgAdapter(Context context, int textViewResourceId, List<Msg> objects) {
super(context, textViewResourceId, objects);
resourceId = textViewResourceId;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Msg msg = getItem(position);
View view;
ViewHolder viewHolder;
if (convertView == null) {
view = LayoutInflater.from(getContext()).inflate(resourceId, null);
viewHolder = new ViewHolder();
viewHolder.leftLayout = (LinearLayout) view
.findViewById(R.id.left_layout);
viewHolder.rightLayout = (LinearLayout) view
.findViewById(R.id.right_layout);
viewHolder.leftMsg = (TextView) view.findViewById(R.id.left_msg);
viewHolder.rightMsg = (TextView) view.findViewById(R.id.right_msg);
view.setTag(viewHolder);
} else {
view = convertView;
viewHolder = (ViewHolder) view.getTag();
}
if (msg.getType() == Msg.TYPE_RECEIVED) {
viewHolder.leftLayout.setVisibility(View.VISIBLE);
viewHolder.rightLayout.setVisibility(View.GONE);
viewHolder.leftMsg.setText(msg.getContent());
} else if(msg.getType() == Msg.TYPE_SEND) {
viewHolder.rightLayout.setVisibility(View.VISIBLE);
viewHolder.leftLayout.setVisibility(View.GONE);
viewHolder.rightMsg.setText(msg.getContent());
}
return view;
}
class ViewHolder {
LinearLayout leftLayout;
LinearLayout rightLayout;
TextView leftMsg;
TextView rightMsg;
}
}
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#d8e0e8"
android:orientation="vertical"
tools:context=".MainActivity" >
<ListView
android:id="@+id/msg_list_view"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:divider="#0000" >
</ListView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<EditText
android:id="@+id/input_text"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:hint="Type something here"
android:maxLines="2" />
<Button
android:id="@+id/send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Send" />
</LinearLayout>
</LinearLayout>msg_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="10dp" >
<LinearLayout
android:id="@+id/left_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:background="@drawable/message_left" >
<TextView
android:id="@+id/left_msg"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="10dp"
android:textColor="#fff" />
</LinearLayout>
<LinearLayout
android:id="@+id/right_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:background="@drawable/message_right" >
<TextView
android:id="@+id/right_msg"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="10dp"/>
</LinearLayout>
</LinearLayout>注意;打开eclipse安装包里的sdk文件夹，然后打开tools文件夹，点击draw9patch.bat，会弹出一个界面，将想要修改的对话框图片导入，添加黑色小点，程序在运行时会自动在合适位置进行拖拉。