对文本消息的数据库查询返回null

Question

好的，我得到了这项服务，它在启动时会查询数据库并通过短信从列中发出字符串。一切正常，除了文本消息继续为空

这是代码：

public class SmsFilterService extends Service{

    SQLiteDatabase db;
    final String dbTable = "Realtor_SMS_Table";
    String messageAddress;
    String messageDescription;
    String messageURL;


    public IBinder onBind(Intent intent) {
        return null;

    }
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    @Override
    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
        Log.d("SmsFilterService", "Service Started");
        filterMessage(dbTable, SMSReceiver.messagefrom, SMSReceiver.messagebody);
    }

    public void filterMessage(String dbTable, String messagefrom,
            String messagebody) {
        String myPath = "/data/data/com.RealtorSMS/databases/RealtorDB.db";
        db = SQLiteDatabase.openDatabase(myPath, null,
                SQLiteDatabase.OPEN_READONLY);

        Cursor cursor = db.query(dbTable, new String[] { "_id", "Description",
                "URL" }, "_id like " + "'%" + messagebody + "%'", null, null,
                null, null);

        Log.d("My SMSReceiver", "sql= " + cursor);
        db.close();


        if (cursor != null) {
            cursor.moveToFirst();

            while (cursor.isAfterLast() == false) {

                messageAddress = cursor.getString(0);
                Log.d("messageAddress", messageAddress);
                messageDescription = cursor.getString(1);
                messageURL = cursor.getString(2);


            }

            SmsManager sm = SmsManager.getDefault();
            sm.sendTextMessage(messagefrom, null, messageAddress + " "
                    + messageDescription, null, null);
            sm.sendTextMessage(messagefrom, null, messageAddress + " "
                    + messageURL, null, null);
        }


        Log.d("SmsFilterService", "Service Destroyed");
        onDestroy();




}
}

我知道条目在数据库中。我的查询有问题吗？

所以我将其改为：

public void filterMessage(String dbTable, String messagefrom,
            String messagebody) {
        String myPath = "/data/data/com.RealtorSMS/databases/RealtorDB.db";
        db = SQLiteDatabase.openDatabase(myPath, null,
                SQLiteDatabase.OPEN_READONLY);
        String dbquery = "select * from " + dbTable + " where _id like \'%"+messagebody+"%\'";
        Cursor cursor = db.rawQuery(dbquery, null);

        Log.d("My SMSReceiver", "sql= " + cursor);
        db.close();


        if (cursor != null) {
            cursor.moveToFirst();

            while (cursor.isAfterLast() == false) {

                messageAddress = cursor.getString(0);
                Log.d("messageAddress", messageAddress);
                messageDescription = cursor.getString(1);
                messageURL = cursor.getString(2);


            }

            SmsManager sm = SmsManager.getDefault();
            sm.sendTextMessage(messagefrom, null, messageAddress + " "
                    + messageDescription, null, null);
            sm.sendTextMessage(messagefrom, null, messageAddress + " "
                    + messageURL, null, null);
        }

我仍然得到空值