ArrayAdapter适配器的用法,模拟QQ发消息界面。

 import java.util.ArrayList;

 import android.app.Activity;
 import android.content.Context;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
 import android.widget.ArrayAdapter;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.ListView;
 import android.widget.TextView;

 public class MainActivity extends Activity {
     EditText et;
     Button btn;
     ListView lv;
     MyAdapter mMyAdapter;
     ArrayList<String> date;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         date = new ArrayList<String>();
         et = (EditText) findViewById(R.id.et1);
         btn = (Button) findViewById(R.id.btn1);
         lv = (ListView) findViewById(R.id.lv);

         mMyAdapter = new MyAdapter(this, R.layout.list);
         // 设置ListView的适配器 （ArrayAdapter适配器的用法）
         lv.setAdapter(mMyAdapter);

         btn.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 sendmessage();
             }
         });
     }

     public void sendmessage() {
         date.add(et.getText().toString());
         mMyAdapter.notifyDataSetChanged();
         // 发送完设置输入框为空
         et.setText(null);
         // 发送消息后将ListView滚动到最下方
         lv.setSelection(ListView.FOCUS_DOWN);
     }

     public class MyAdapter extends ArrayAdapter {
         private Context context;
         private int resource;

         public MyAdapter(Context context, int resource) {
             super(context, resource);
             this.resource = resource;
             this.context = context;
         }

         @Override
         public int getCount() {

             return date.size();
         }

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

             LayoutInflater flater = LayoutInflater.from(context);
             // 设置可以复用view
             if (convertView == null) {
                 convertView = flater.inflate(resource, null);
             }
             TextView tv = (TextView) convertView.findViewById(R.id.qqtxt);
             tv.setText(date.get(position));

             return convertView;
         }

     }
 }

xml文件：

 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/RelativeLayout1"
     android:layout_width="match_parent"
     android:layout_height="match_parent" >

     <ImageView
         android:id="@+id/ImageView1"
         android:layout_width="50dp"
         android:layout_height="50dp"
         android:layout_alignParentRight="true"
         android:layout_centerVertical="true"
         android:background="@drawable/meimei" />

     <TextView
         android:id="@+id/qqtxt"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_centerVertical="true"
         android:layout_toLeftOf="@+id/ImageView1"
         android:background="#ff5252"
         android:text="1233"
         android:textSize="20sp" />

 </RelativeLayout>

 <RelativeLayout 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"
     tools:context="com.lixu.qqduihua.MainActivity" >

     <ListView
         android:id="@+id/lv"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_above="@+id/commentLinearLayout"
         android:layout_alignParentTop="true"
         android:divider="@android:color/transparent"
         android:dividerHeight="15dip"
         android:scrollbars="none" />

     <LinearLayout
         android:id="@+id/commentLinearLayout"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_alignParentBottom="true"
         android:background="#e0e0e0"
         android:orientation="horizontal" >

         <EditText
             android:id="@+id/et1"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_weight="2"
             android:ems="10"
             android:hint="请输入内容" >

             <requestFocus />
         </EditText>

         <Button
             android:id="@+id/btn1"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:background="@drawable/round"
             android:text="发送" />
     </LinearLayout>

 </RelativeLayout>

运行效果：