我在Android Studio中創建了一個遊戲,現在我試圖在數據庫中插入一個分數。我創建了一個SQL腳本,可以很好地創建數據庫,但現在我試圖插入信息,但是我沒有上下文。如何從非活動類中獲取上下文
這是我將對DBAdapter:
public class DBAdapter {
private SQLiteDatabase database;
private ScriptSQL dbHelper;
private String[] allColumns = {ScriptSQL.ID, ScriptSQL.PONTUACAO};
public DBAdapter(Context ctx) {
dbHelper = new ScriptSQL(ctx);
}
public void open() throws SQLException {
database = dbHelper.getWritableDatabase();
}
public void openRead() throws SQLException {
database = dbHelper.getReadableDatabase();
}
public void close() {
dbHelper.close();
}
public Score createScore(String pontuacao) {
ContentValues values = new ContentValues();
values.put(dbHelper.PONTUACAO, pontuacao);
long insertId = database.insert(dbHelper.TABLE_NAME, null, values);
// To show how to query
Cursor cursor = database.query(dbHelper.TABLE_NAME, allColumns, dbHelper.ID + " = " + insertId, null, null, null, null);
cursor.moveToFirst();
return cursorToScore(cursor);
}
這是我試圖讓背景下的非活性類。
World.java
public class World {
static final int WORLD_WIDTH = 10; //largura
static final int WORLD_HEIGHT = 13; //altura
static final int SCORE_INCREMENT = 10; //incremento do score
static final float TICK_INITIAL = 0.8f; //velocidade inicial do jogo
static final float TICK_DECREMENT = 0.2f; //velocidade de decremento
public Dog dog;
public Elements element;
public boolean EndGame = false;
public int score = 0;
static int put_element = 0;
public List<Elements> elements = new ArrayList<Elements>();
Random random = new Random();
float timeTick = 0;
static float tick = TICK_INITIAL;
public World(){
dog = new Dog();
}
/*...*/
DBAdapter datasource;
private Context context;
public void update_database(){
datasource = new DBAdapter(context.getApplicationContext());
try {
datasource.open();
String point = Integer.toString(score);
Score c = datasource.createScore(point);
datasource.close();
}
catch (SQLException ex) { }
}
的問題是就行:
數據源=新將對DBAdapter(context.getApplicationContext());
我試圖這樣做,但它給出了一個錯誤,因爲這是一個非活動類。
datasource = new DBAdapter(this);
我該怎麼辦?
重複問題 –