Android 设计模式之观察者模式

这里有一个观察者模式的例子，使用 ContentObserver 监听数据库变化

如何接受指定号码的短信，并且不让系统截取到通知用户

public class ScreenTest extends Activity {

class SmsContent extends ContentObserver{

private Cursor cursor = null;

public SmsContent(Handler handler) {

super(handler);

}

//检查与观察函数 deliverSelfNotifications()。（它将返回 false 默认情况下）@Override

public boolean deliverSelfNotifications() {

return true;

}
/**

* @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

*/
@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);}}