Доброго времени суток.
Никак не могу обнаружить причину проблемы, а конкретнее:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.test_apps.slandshow.controlyourcash/com.test_apps.slandshow.controlyourcash.view.CashSettingsActivity}: android.database.sqlite.SQLiteException: Can't downgrade database from version 2 to 1
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
aused by: android.database.sqlite.SQLiteException: Can't downgrade database from version 2 to 1
at android.database.sqlite.SQLiteOpenHelper.onDowngrade(SQLiteOpenHelper.java:360)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:254)
at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:187)
at com.test_apps.slandshow.controlyourcash.model.CashDBHandler.getAllProducts(CashDBHandler.java:47)
at com.test_apps.slandshow.controlyourcash.view.CashSettingsActivity.displayProductList(CashSettingsActivity.java:129)
at com.test_apps.slandshow.controlyourcash.view.CashSettingsActivity.onCreate(CashSettingsActivity.java:55)
UPDATE: Поменял версию на 2, но возникла проблема с другим: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.test_apps.slandshow.controlyourcash/com.test_apps.slandshow.controlyourcash.view.CashSettingsActivity}: android.database.sqlite.SQLiteException: no such column: income (code 1): , while compiling: SELECT _id, productname, coast, income FROM products
У меня есть класс
CashSettingsActivity, который манипулирует классом
CashDBHandler.
Вот сокращённый код класса
CashDBHandler (некоторые методы опущены для читабельности):
public class CashDBHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "productDB.db";
public static final String TABLE_PRODUCTS = "products";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_PRODUCTNAME = "productname";
public static final String COLUMN_INCOME = "income";
public static final String COLUMN_COAST = "coast";
public CashDBHandler(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
String create_products_table = "CREATE TABLE " + TABLE_PRODUCTS + " (" +
COLUMN_ID + " INTEGER PRIMARY KEY, " + COLUMN_PRODUCTNAME + " TEXT," +
COLUMN_COAST + " INTEGER, " + COLUMN_INCOME + "INTEGER)";
db.execSQL(create_products_table);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_PRODUCTS);
onCreate(db);
}
// Ошибка!
public Cursor getAllProducts() {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_PRODUCTS, new String[]{COLUMN_ID, COLUMN_PRODUCTNAME,
COLUMN_COAST, COLUMN_INCOME}, null, null, null, null, null); // Ошибка!
if (cursor != null) {
cursor.moveToFirst();
return cursor;
} else {
return null;
}
}
public void addProduct(Cash product) {
ContentValues values = new ContentValues();
values.put(COLUMN_PRODUCTNAME, product.getName());
values.put(COLUMN_COAST, product.getCoast());
values.put(COLUMN_INCOME, product.getIncome());
SQLiteDatabase db = this.getWritableDatabase();
db.insert(TABLE_PRODUCTS, null, values);
db.close();
}
...
}
А вот краткое описание класса
CashSettingsActivity:
public class CashSettingsActivity extends AppCompatActivity {
private CashDBHandler dbHandler;
private SimpleCursorAdapter simpleCursorAdapter;
private TextView idView;
private EditText etName;
private EditText etCoast;
private EditText etIncome;
private ListView lvProducts;
private HashMap<Long, String> map;
@Override
protected void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.cash_database);
idView = (TextView) findViewById(R.id.tvID);
etName = (EditText) findViewById(R.id.etName);
etCoast = (EditText) findViewById(R.id.etCoast);
etIncome = (EditText) findViewById(R.id.etIncome);
lvProducts = (ListView) findViewById(R.id.productList);
dbHandler = new CashDBHandler(this, null, null, 1);
displayProductList();
setHandler(lvProducts);
}
public void newProduct(View v) {
Cash p = new Cash(etName.getText().toString(),
Integer.parseInt(etCoast.getText().toString()),
Integer.parseInt(etIncome.getText().toString()));
dbHandler.addProduct(p);
idView.setText("Record Added!");
etName.setText("");
etCoast.setText("");
etIncome.setText("");
displayProductList();
}
// Ошибка!
private void displayProductList() {
Cursor cursor = dbHandler.getAllProducts(); // Тут происходит ошибка!
if (cursor == null) {
idView.setText("Unable to generate cursor.");
return;
}
if (cursor.getCount() == 0) {
idView.setText("No Products in the Database.");
return;
}
String[] columns = new String[]{
CashDBHandler.COLUMN_ID,
CashDBHandler.COLUMN_PRODUCTNAME,
CashDBHandler.COLUMN_COAST,
CashDBHandler.COLUMN_INCOME
};
int[] boundTo = new int[]{
R.id.pId,
R.id.pName,
R.id.pCoast,
R.id.pIncome
};
simpleCursorAdapter = new SimpleCursorAdapter(this,
R.layout.activity_cash_settings,
cursor,
columns,
boundTo,
0);
lvProducts.setAdapter(simpleCursorAdapter);
}
...
Таким образом, при исполнении инструкции:
SQLiteDatabase db = this.getReadableDatabase();
Вылетает исключение, благодаря которому я не могу создать таблицу.
Никак не могу понять, что же я делаю не так?
