Question

我有四个表的android Sqlite数据库，我想在我需要的时候在活动的每个地方获得custumer_data“cust_id”的值。我在活动中获得了cust_id的值，但是当我在另一个活动中实现相同的方法时，cust_id的值显示为null。这是我的数据库类：

public class SctDatabaseHelper extends SQLiteOpenHelper {
Cursor cursor;
private static final String LOG = "sctDatabaseHelper";
private static final String DATABASE_NAME = "sctnetwork";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_CUSTIMER_DATA = "customer_data";
private static final String TABLE_FRIEND_LIST = "friend_list";
private static final String TABLE_PROFILE = "profile";
private static final String TABLE_REGISTRATION_FLAG = "registration_flag";

//element of table custumer data
private static final String KEY_ID = "id";
private static final String KEY_APP_LOCK = "app_lock";
private static final String KEY_CURR_CODE = "curr_code";
private static final String KEY_CURR_TYPE = "curr_type";
private static final String KEY_CUST_ID_CUSTUMER = "cust_id";
private static final String KEY_FIRST_NAME = "first_name";
private static final String KEY_LAST_NAME = "last_name";
private static final String KEY_L_PIN = "l_pin";
private static final String KEY_PIN_FLAG = "pin_flag";
private static final String KEY_PIN_RETRIES_COUNT = "pin_retries_count";
private static final String KEY_RESET_PIN = "reset_pin";

//element of table friend list

private static final String KEY_CELL_NO = "cell_no";
private static final String KEY_CUST_ID_FRIEND = "cust_id";
private static final String KEY_NAME = "name";

//element of table profile
private static final String KEY_ACT_FLAG = "act_flag";
private static final String KEY_CARD_TYPE = "card_type";
private static final String KEY_EXP_DATE = "exp_date";
private static final String KEY_LAST_FOUR = "last_4";
private static final String KEY_PROFILE_NAME = "profile_name";

//element of table registration flag
private static final String KEY_REG_FLAG = "reg_flag";

//crete table custumer data
private static final String CREATE_TABLE_CUSTUMER_DATA = "create table " + TABLE_CUSTIMER_DATA + "(" + KEY_ID + " integer primary key, " + KEY_CUST_ID_CUSTUMER + " text ," + KEY_APP_LOCK + " text, " + KEY_CURR_CODE + " text, " + KEY_CURR_TYPE + " text, " + KEY_FIRST_NAME + " text, " + KEY_LAST_NAME + " text ," + KEY_L_PIN + " text ," + KEY_PIN_FLAG + " text, " + KEY_PIN_RETRIES_COUNT + " text, " + KEY_RESET_PIN + " text " + ")";
//create table friend list
private static final String CREATE_TABLE_FRIEND_LIST = "create table " + TABLE_FRIEND_LIST + "(" + KEY_CELL_NO + " text, " + KEY_CUST_ID_FRIEND + " text, " + KEY_NAME + " text " + ")";
// create table profile
private static final String CREATE_TABLE_PROFILE = " create table " + TABLE_PROFILE + "(" + KEY_ACT_FLAG + " text, " + KEY_CARD_TYPE + " text ," + KEY_EXP_DATE + " text, " + KEY_LAST_FOUR + " text, " + KEY_PROFILE_NAME + " text " + ")";

// create table of registration flag
private static final String CREATE_TABLE_FLAG = " create table " + TABLE_REGISTRATION_FLAG + "(" + KEY_REG_FLAG + " text " + ")";


public SctDatabaseHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL(CREATE_TABLE_CUSTUMER_DATA);
    db.execSQL(CREATE_TABLE_FLAG);
    db.execSQL(CREATE_TABLE_FRIEND_LIST);
    db.execSQL(CREATE_TABLE_PROFILE);
    Log.d("custumer_data", CREATE_TABLE_CUSTUMER_DATA);
    Log.d("flag", CREATE_TABLE_FLAG);
    Log.d("friend_list", CREATE_TABLE_FRIEND_LIST);
    Log.d("profile", CREATE_TABLE_PROFILE);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_CUSTIMER_DATA);
    db.execSQL("DROP IF EXISTS " + TABLE_FRIEND_LIST);
    db.execSQL("DROP IF EXISTS " + TABLE_REGISTRATION_FLAG);
    db.execSQL("DROP IF EXISTS " + TABLE_PROFILE);

}

public long createCustumer(Customer_Data customer_data) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();

    values.put(KEY_APP_LOCK, customer_data.getApp_lock());
    values.put(KEY_FIRST_NAME, customer_data.getFirst_name());
    values.put(KEY_LAST_NAME, customer_data.getLast_name());
    values.put(KEY_L_PIN, customer_data.getL_pin());
    values.put(KEY_PIN_FLAG, customer_data.getPin_flag());
    values.put(KEY_PIN_RETRIES_COUNT, customer_data.getPin_retries_count());
    values.put(KEY_RESET_PIN, customer_data.getReset_pin());

    long custumer = sqLiteDatabase.insert(TABLE_CUSTIMER_DATA, null, values);
    return custumer;
}

public long insertProfile( String expdate, String last_4,String flag,String Dummy) {
    SQLiteDatabase sqLiteDatabase = this.getReadableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(KEY_EXP_DATE, expdate);
    contentValues.put(KEY_LAST_FOUR, last_4);
    contentValues.put(KEY_ACT_FLAG,flag);
    contentValues.put(KEY_PROFILE_NAME,Dummy);
    return sqLiteDatabase.insert(TABLE_PROFILE, null, contentValues);

}
public long insertProfile(String cardtype) {
    SQLiteDatabase sqLiteDatabase = this.getReadableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(KEY_CARD_TYPE, cardtype);
    return sqLiteDatabase.insert(TABLE_PROFILE, null, contentValues);

}

public long insertCutid(String str) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_CUST_ID_CUSTUMER, str);
    return sqLiteDatabase.insert(TABLE_CUSTIMER_DATA, null, values);
}

public long insertCtypeCcode(String type, String code) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_CURR_TYPE, type);
    values.put(KEY_CURR_CODE, code);
    return sqLiteDatabase.insert(TABLE_CUSTIMER_DATA, null, values);
}

public long insertFLname(String first, String last) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_FIRST_NAME, first);
    values.put(KEY_LAST_NAME, last);
    return sqLiteDatabase.insert(TABLE_CUSTIMER_DATA, null, values);
}

public long createProfile(Profile profile) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_ACT_FLAG, profile.getAct_flag());
    values.put(KEY_CARD_TYPE, profile.getCard_type());
    values.put(KEY_EXP_DATE, profile.getExp_date());
    values.put(KEY_LAST_FOUR, profile.getLast_4());
    values.put(KEY_PROFILE_NAME, profile.getProfile_name());
    long profileinsert = sqLiteDatabase.insert(TABLE_PROFILE, null, values);
    return profileinsert;
}

public long createFriendlist(Friends_List friends_list) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_CELL_NO, friends_list.getCell_no());
    values.put(KEY_CUST_ID_CUSTUMER, friends_list.getCust_id());
    values.put(KEY_NAME, friends_list.getName());
    long friendlistinsert = sqLiteDatabase.insert(TABLE_FRIEND_LIST, null, values);
    return friendlistinsert;
}

public long createRegFlag(String str) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(KEY_REG_FLAG, str);
    long regflaginsert = sqLiteDatabase.insert(TABLE_REGISTRATION_FLAG, null, values);
    return regflaginsert;
}

public int checkHasCustData() {
    boolean data;
    String selectquery = "select * from " + TABLE_CUSTIMER_DATA;
    Log.d("custumer", selectquery);
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(selectquery, null);
    int custmr_count = cursor.getCount();
    cursor.close();
    db.close();
    return custmr_count;
}

public int checkRegData() {
    boolean flag;
    String selectquery = " select * from " + TABLE_REGISTRATION_FLAG;
    SQLiteDatabase sqLiteDatabase = this.getReadableDatabase();
    Cursor cursor = sqLiteDatabase.rawQuery(selectquery, null);
    int reg_count = cursor.getCount();
    cursor.close();
    sqLiteDatabase.close();
    return reg_count;

}

public String getCu_id() {
    String bankbalresult = null;
    SQLiteDatabase db = this.getReadableDatabase();
    String selectquery = "select cust_id from  customer_data";
    Cursor cursor = db.rawQuery(selectquery, null);
    if (cursor != null && cursor.getCount() > 0) {
        cursor.moveToFirst();
        do {
            bankbalresult = cursor.getString(cursor.getColumnIndex("cust_id"));
        } while (cursor.moveToNext());
    }
    return bankbalresult;
}

public String getFlag() {
    String bankbalresult = null;
    SQLiteDatabase db = this.getReadableDatabase();
    String selectquery = "select reg_flag from  registration_flag";
    Cursor cursor = db.rawQuery(selectquery, null);
    if (cursor != null && cursor.getCount() > 0) {
        cursor.moveToFirst();
        do {
            bankbalresult = cursor.getString(cursor.getColumnIndex("reg_flag"));
        } while (cursor.moveToNext());
    }
    return bankbalresult;
}

public int updateFlag(String str) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues value = new ContentValues();
    value.put(KEY_REG_FLAG, str);
    return db.update(TABLE_REGISTRATION_FLAG, value, KEY_REG_FLAG + " = ?", new String[]{str});

}

}

代码用于访问活动中的cust_id是：

    private SctDatabaseHelper sctDatabaseHelper;

   @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        sctDatabaseHelper = new SctDatabaseHelper(this);
        sctDatabaseHelper.getReadableDatabase();

    }

我用cust_id使用这个：

 String id = sctDatabaseHelper.getCu_id();

通过使用这个我在一个活动中得到cust_id的值，但使用相同的方法到其他但不能得到。问题是什么？帮助我

Answer 1

在customer_data表格中，您已创建id作为主键。

当您创建表时，您尚未将主键声明为自动增量，并且当您插入表时，您没有提供任何ID。

因此，当您插入时，您的主键不是按照您的意愿形成的。

尝试这样的事情

//crete table custumer data
private static final String CREATE_TABLE_CUSTUMER_DATA = "create table " + TABLE_CUSTIMER_DATA + "(" + KEY_ID + " integer primary key autoincrement, " + KEY_CUST_ID_CUSTUMER + " text ," + KEY_APP_LOCK + " text, " + KEY_CURR_CODE + " text, " + KEY_CURR_TYPE + " text, " + KEY_FIRST_NAME + " text, " + KEY_LAST_NAME + " text ," + KEY_L_PIN + " text ," + KEY_PIN_FLAG + " text, " + KEY_PIN_RETRIES_COUNT + " text, " + KEY_RESET_PIN + " text " + ");";

我也注意到在create table字符串中，你还没有添加';'在末尾。

您需要将活动代码更改为此类 -

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        sctDatabaseHelper = new SctDatabaseHelper(this);
        sct.getCu_id();

    }

您还需要将getCu_id()方法更改为此类

public String getCu_id() {
    String bankbalresult = null;
    SQLiteDatabase db = this.getReadableDatabase();
    String selectquery = "select "+KEY_CUST_ID_CUSTUMER+" from "+TABLE_CUSTIMER_DATA+";";
    Cursor cursor = db.rawQuery(selectquery, null);
    if (cursor != null && cursor.getCount() > 0) {
        for(c.moveToFirst();!c.isAfterLast();c.moveToNext())
            bankbalresult = cursor.getString(cursor.getColumnIndex(KEY_CUST_ID_CUSTUMER));
        } 
    }
    return bankbalresult;
}

这将为您提供存储在表格中的最后一个客户ID。

如果您想要存储所有客户ID，那么您可以执行类似这样的操作

 public String getCu_id() {
        String bankbalresult = null;
        SQLiteDatabase db = this.getReadableDatabase();
        String selectquery = "select "+KEY_CUST_ID_CUSTUMER+" from "+TABLE_CUSTIMER_DATA+";";
        Cursor cursor = db.rawQuery(selectquery, null);
        if (cursor != null && cursor.getCount() > 0) {
            for(c.moveToFirst();!c.isAfterLast();c.moveToNext())
                bankbalresult+ = cursor.getString(cursor.getColumnIndex(KEY_CUST_ID_CUSTUMER))+"!";
            } 
        }
        return bankbalresult;
    }

然后你可以{！1}将你的字符串放在'！'并形成所有客户ID的数组。

在split语句中，您最后没有添加select。希望这会有所帮助：）

Android SQlite数据库无法从数据库中获取价值

1 个答案: