Android SQlite Datenbanken kann keinen Wert aus Datenbanken

Question

Ich habe Android Sqlite-Datenbanken mit vier Tabelle, ich möchte Wert von custumer_data "cust_id" erhalten, wo immer in der Aktivität, wann immer ich brauche. Ich erhalte den Wert von cust_id in Aktivität, aber wenn ich dieselbe Methode in einer anderen Aktivität implementiere, ist der Wert von cust_id zeigt null. Hier ist meine Datenbank-Klasse:

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}); 

} 

}

Und Code Gebrauch zu cust_id in Aktivität Acess ist:

private SctDatabaseHelper sctDatabaseHelper; 

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

    } 

und ich bekomme cust_id mit diesem:

String id = sctDatabaseHelper.getCu_id(); 

indem ich das benutze, bekomme ich den Wert cust_id in einer Aktivität aber benutze die gleiche Methode zu anderen aber kann nicht bekommen. Was ist das Problem? help me

Answer 1

In Ihrer customer_data Tabelle haben Sie id als Primärschlüssel erstellt.

Wenn Sie Ihre Tabelle erstellen, haben Sie Ihren Primärschlüssel nicht als Autoinkrement deklariert, und wenn Sie ihn in die Tabelle einfügen, geben Sie keine ID an.

Wenn Sie also einfügen, wird Ihr Primärschlüssel nicht wie gewünscht geformt.

Probieren Sie etwas wie dieses

//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 " + ");"; 

Ich habe auch bemerkt, dass in der Tabelle Zeichenfolgen erstellen, haben Sie nicht hinzugefügt ‚;‘ Am Ende.

Sie benötigen Sie Aktivitätscode zu so etwas wie this-

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

    } 

Sie auch Ihre getCu_id() Methode, um etwas zu ändern, wie diese

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; 
} 

ändern müssen

Dies gibt Ihnen die letzten Kunden-ID in Ihrer Tabelle gespeichert.

Wenn Sie alle Kunden-IDs möchten, die gespeichert sind, dann können Sie so etwas wie dieses

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; 
    } 

tun Dann können Sie Ihre Zeichenfolge an split ‚!‘ und ein Array aller Kunden-IDs bilden. In Ihren select Anweisungen haben Sie am Ende ; nicht hinzugefügt this helps :)