Android UI学习之ListView（使用BaseAdapter）

<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"
    tools:context="${relativePackage}.${activityClass}" >
	<ListView 
	    android:id="@+id/lv"
	    android:layout_width="match_parent"
	    android:layout_height="match_parent"
	    >
	</ListView>
</LinearLayout>

<?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" >
    <TextView 
        android:id="@+id/tv_phone"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        />
    <TextView 
        android:id="@+id/tv_body"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:singleLine="true"
        android:ellipsize="end"
        />
</LinearLayout>

public class MainActivity extends Activity {
	List<Message> list;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        list = new ArrayList<Message>();
        
    	//得到ContentResolver
    	ContentResolver cr = getContentResolver();
    	
    	//查询系统的短信，只需要查询我们关心的字段
    	Cursor cursor = cr.query(Uri.parse("content://sms"), new String[]{"address", "date", "type", "body"}, 
    			null, null, null);
    	
    	//取出查询到的信息
    	while(cursor.moveToNext())
    	{
    		String address = cursor.getString(cursor.getColumnIndex("address"));
    		String date = cursor.getString(cursor.getColumnIndex("date"));
    		String type = cursor.getString(cursor.getColumnIndex("type"));
    		String body = cursor.getString(cursor.getColumnIndex("body"));
    		
    		//将每条短信放入List集合中
    		Message msg = new Message(address, date, type, body);
    		list.add(msg);
    	}
    	
    	//获取到listview
    	ListView listView = (ListView) findViewById(R.id.lv);
    	//设置适配器
    	listView.setAdapter(new MyAdapter());
    }
    
    //定义MyAdapter继承BaseAdapter
    class MyAdapter extends BaseAdapter
    {
    	@Override
		public int getCount() {
    		//返回显示元素的个数
			return list.size();
		}

    	//返回每个元素的，可以不用关心
		@Override
		public Object getItem(int arg0) {
			return null;
		}

		@Override
		public long getItemId(int arg0) {
			//返回当前元素的id，可以不用关心
			return 0;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup arg2) {
			// 返回一个在listView中显示的对象
			
			//获得消息的对象
			Message message = list.get(position);
			
			//创建一个布局填充器对象
			LayoutInflater inflater = LayoutInflater.from(MainActivity.this);
			//从布局填充器中拿到View对象
			View view = inflater.inflate(R.layout.item_list, null);
			
			//找到TextView对象
			TextView phone = (TextView) view.findViewById(R.id.tv_phone);
			phone.setText(message.getAddress());
			
			//找到TextView对象
			TextView body = (TextView) view.findViewById(R.id.tv_body);
			body.setText(message.getBody());
			
			return view;
		}
    }
}

public class Message {
	private String address; //号码
	private String date;    //时间
	private String type;    //类型：1为发生，2为接受
	private String body;    //短信内容
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getDate() {
		return date;
	}
	public void setDate(String date) {
		this.date = date;
	}
	public String getType() {
		return type;
	}
	public void setType(String type) {
		this.type = type;
	}
	public String getBody() {
		return body;
	}
	public void setBody(String body) {
		this.body = body;
	}
}

			//创建一个布局填充器对象
			LayoutInflater	inflater = LayoutInflater.from(MainActivity.this);
			View view = null;
			if(convertView == null)
			{
				//从布局填充器中拿到View对象
				view = inflater.inflate(R.layout.item_list, null);	
			}
			else {
				
				view = convertView;
			}