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); 
    }
}

<receiver android:name="BootCompletedReceiver" android:permission="android.permission.RECEIVE_BOOT_COMPLETED" >
	<intent-filter>
		<action android:name="android.intent.action.BOOT_COMPLETED"/>
		<action android:name="android.intent.action.USER_PRESENT"/>
	</intent-filter>
</receiver>