使用ContentObserver监听数据库变化

public class ScreenTest extends Activity {   
       
    class SmsContent extends ContentObserver{   
        private Cursor cursor = null;   
        public SmsContent(Handler handler) {   
            super(handler);   
        }   
           
        /**  
         * @Description 当短信表发送改变时，调用该方法   
         *              需要两种权限  
         *              android.permission.READ_SMS读取短信  
         *              android.permission.WRITE_SMS写短信  
         * @Author Snake  
         * @Date 2010-1-12  
         */  
        @Override  
        public void onChange(boolean selfChange) {   
            // TODO Auto-generated method stub   
            super.onChange(selfChange);   
            //读取收件箱中指定号码的短信   
            cursor = managedQuery(Uri.parse("content://sms/inbox"), new String[]{"_id", "address", "read"}, " address=? and read=?", new String[]{"12345678901", "0"}, "date desc");   
               
            if (cursor != null){   
                ContentValues values = new ContentValues();   
                values.put("read", "1");        //修改短信为已读模式   
                cursor.moveToFirst();   
                while (cursor.isLast()){   
                    //更新当前未读短信状态为已读   
                    getContentResolver().update(Uri.parse("content://sms/inbox"), values, " _id=?", new String[]{""+cursor.getInt(0)});   
                    cursor.moveToNext();   
                }   
            }   
        }   
    }   
       
    /** Called when the activity is first created. */  
    @Override  
    public void onCreate(Bundle savedInstanceState) {   
        super.onCreate(savedInstanceState);   
        setContentView(R.layout.main);   
        SmsContent content = new SmsContent(new Handler());   
        //注册短信变化监听   
        this.getContentResolver().registerContentObserver(Uri.parse("content://sms/"), true, content);    
    }   
}