java - SQLite 连接对象泄露 - Android

Question

我正在制作我的第一个 Android 应用程序，我首先学习了一些 sqlite 教程，这些教程教我使用扩展 SQLiteOpenHelper 的 databaseHelper。所以我的 databaseHelper 确实扩展了 SQLiteOpenHelper。我在 Logcat 中收到了一个 sqlite 连接泄漏警告，因此想要一些关于如何修复该问题的建议。

我收到这个错误:

02-01 21:39:50.740: W/SQLiteConnectionPool(32061): A SQLiteConnection object for database '/data/data/com.btf271.fashionassistant/databases/clothingManager' was leaked!  Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.

在发生泄漏的地方调用我的 databaseHelper 函数:

 public List<Sticker> getObjectsByGenderAndCategory(String gender, String category) {
        List<Sticker> objects = new ArrayList<Object>();
        String selectQuery = String.format(
                "SELECT * FROM %s WHERE %s = \"%s\" AND %s = \"%s\"",
                TABLE_OBJECT, KEY_GENDER, gender, KEY_CATEGORY, category);

        Log.e(LOG, selectQuery);

        SQLiteDatabase db = this.getReadableDatabase();
        Cursor c = db.rawQuery(selectQuery, null);
     try{
        // looping through all rows and adding to list
        if (c.moveToFirst()) {
            do {
                Object o = createClothingItemJavaObject(c);

                // adding to object list
                objects.add(o);
            } while (c.moveToNext());
        }
     }finally {
           c.close();
db.close();
     }
        return objects;
    }

我找到了 this which I will try tomorrow. It's late .

谢谢。

Answer 1

我所做的只是implement this answer to a similar question现在它不显示 SQL 连接对象泄漏错误。我怎么推荐都不为过。实现和工作只花了几分钟。

代码如下:

public class DatabaseHelper extends SQLiteOpenHelper { 

  private static DatabaseHelper mInstance = null;

  private static final String DATABASE_NAME = "database_name";
  private static final String DATABASE_TABLE = "table_name";
  private static final int DATABASE_VERSION = 1;

  public static DatabaseHelper getInstance(Context ctx) {

    // Use the application context, which will ensure that you 
    // don't accidentally leak an Activity's context.
    // See this article for more information: http://bit.ly/6LRzfx
    if (mInstance == null) {
      mInstance = new DatabaseHelper(ctx.getApplicationContext());
    }
    return mInstance;
  }

  /**
   * Constructor should be private to prevent direct instantiation.
   * make call to static factory method "getInstance()" instead.
   */
  private DatabaseHelper(Context ctx) {
    super(ctx, DATABASE_NAME, null, DATABASE_VERSION);
  }
}