Итак, я пытался сохранить результат из моего метода SELECT, ничего не возвращая.
Я не уверен, что я делаю неправильно.Буду признателен за любую помощь!
Вывод этой функции getData () - "".Ничего в этом нет вообще.
Мой код внизу:
public String getData(int firstSelection, int secondSelection, int thirdSelection,
int fourthSelection, int fifthSelection)
{
SQLiteDatabase db = dbHelper.getWritableDatabase();
String firstSelectionStr, secondSelectionStr, thirdSelectionStr, fourthSelectionStr, fifthSelectionStr;
firstSelectionStr = Integer.toString(firstSelection);
secondSelectionStr = Integer.toString(secondSelection);
thirdSelectionStr = Integer.toString(thirdSelection);
fourthSelectionStr = Integer.toString(fourthSelection);
fifthSelectionStr = Integer.toString(fifthSelection);
String[] columns = {DBHelper.UID,DBHelper.CNAME};
//Cursor cursor = db.query(DBHelper.TABLE_NAME,columns,null,null,null,null,null);
String selectQuery = "SELECT " + DBHelper.CNAME + " FROM "+ DBHelper.TABLE_NAME + " WHERE First_Attribute=? "
+ " AND Second_Attribute=? " + " AND Third_Attribute=? " + " AND Fourth_Attribute=? "
+ " AND Fifth_Attribute=? ";
Cursor cursor=db.rawQuery(selectQuery, new String[] {firstSelectionStr, secondSelectionStr, thirdSelectionStr,
fourthSelectionStr, fifthSelectionStr});
StringBuilder buffer = new StringBuilder();
// Append every data together
while (cursor.moveToNext())
{
//int cursorID = cursor.getInt(cursor.getColumnIndex(DBHelper.UID));
String chosenItem = cursor.getString(cursor.getColumnIndex(DBHelper.CNAME));
buffer.append(chosenItem + "/n");
}
return buffer.toString();
}
Моя модель базы данных тоже внизу.У меня есть две таблицы.Один для коллекции поделок, который является TABLE_NAME, и другой, где будут храниться выбранные поделки, который является RESULT_TABLE.
static class DBHelper extends SQLiteOpenHelper
{
private static final String DATABASE_NAME = "CraftsAppDatabase.db"; // Database Name
private static final String TABLE_NAME = "CraftTools"; // Table Name
private static final String RESULT_TABLE = "Result"; // Table Name
private static final int DATABASE_Version = 1; // Database Version
private static final String UID="_id"; // Column I (Primary Key)
private static final String CNAME = "Craft_Name"; //Column II
private static final String RESULT = "Result_Name"; //Column II
private static final String FIRST_ATTRIBUTE = "First_Attribute"; //Column III
private static final String SECOND_ATTRIBUTE = "Second_Attribute"; //Column IV
private static final String THIRD_ATTRIBUTE = "Third_Attribute"; //Column V
private static final String FOURTH_ATTRIBUTE = "Fourth_Attribute"; //Column VI
private static final String FIFTH_ATTRIBUTE = "Fifth_Attribute"; //Column VII
private static final String CREATE_TABLE = "CREATE TABLE "+TABLE_NAME+
" ("+UID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+CNAME+" VARCHAR(255)" +
", "+FIRST_ATTRIBUTE+" VARCHAR(255), "+SECOND_ATTRIBUTE+" VARCHAR(255)" +
", "+THIRD_ATTRIBUTE+" VARCHAR(255), "+FOURTH_ATTRIBUTE+" VARCHAR(255)" +
", "+FIFTH_ATTRIBUTE+" VARCHAR(255));";
private static final String CREATE_OTHER_TABLE = "CREATE TABLE "+RESULT_TABLE+
" ("+UID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+RESULT+" VARCHAR(255));";
private static final String DROP_TABLE ="DROP TABLE IF EXISTS "+RESULT_TABLE;
private Context context;
public DBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_Version);
this.context=context;
}
/*public void deleteTable(SQLiteDatabase db) {
db = getWritableDatabase();
db.execSQL("DROP TABLE IF EXISTS CraftTools");
}*/
public void onCreate(SQLiteDatabase db) {
db.execSQL(DROP_TABLE);
db.execSQL(CREATE_OTHER_TABLE);
db.execSQL(CREATE_TABLE);
db.execSQL("INSERT INTO " + TABLE_NAME + "(Craft_Name, First_Attribute, Second_Attribute, Third_Attribute, Fourth_Attribute, Fifth_Attribute ) " +
"VALUES ('Landscape Drawing', '1', '4','8', '0', '0')");
db.execSQL("INSERT INTO " + TABLE_NAME + "(Craft_Name, First_Attribute, Second_Attribute, Third_Attribute, Fourth_Attribute, Fifth_Attribute ) " +
"VALUES ('Popsicle Sticks House', '2', '3','0', '0', '0')");
db.execSQL("INSERT INTO " + TABLE_NAME + "(Craft_Name, First_Attribute, Second_Attribute, Third_Attribute, Fourth_Attribute, Fifth_Attribute ) " +
"VALUES ('Sunset Painting', '4', '7','10', '0', '0')");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//db.execSQL(DROP_TABLE);
onCreate(db);
if (newVersion > oldVersion) {
db.execSQL("ALTER TABLE CraftTools ADD COLUMN FIRST_ATTRIBUTE INTEGER DEFAULT 0");
db.execSQL("ALTER TABLE CraftTools ADD COLUMN SECOND_ATTRIBUTE INTEGER DEFAULT 0");
db.execSQL("ALTER TABLE CraftTools ADD COLUMN THIRD_ATTRIBUTE INTEGER DEFAULT 0");
db.execSQL("ALTER TABLE CraftTools ADD COLUMN FOURTH_ATTRIBUTE INTEGER DEFAULT 0");
db.execSQL("ALTER TABLE CraftTools ADD COLUMN FIFTH_ATTRIBUTE INTEGER DEFAULT 0");
}
}
}
}