Question

美好的一天，我的小部件应用程序上的sqlite数据库存在此问题，即使我明确地调用它也永远不会关闭。我得到这个logcat错误

02-26 00:49:42.070: E/Database(18049): android.database.sqlite.DatabaseObjectNotClosedException: Application did not close the cursor or database object that was opened here

由于某种原因，当我得到一个游标并调用getCount（）方法时，它总是递增，同时也添加了最后一个值。例如..如果我得到游标并且getCount（）方法从列返回值5，我稍后删除小部件。当我再次添加小部件并查询我知道值为6的不同列时，我将从光标返回11作为返回值。 getCount（）方法。它就像光标一样，数据库永远不会关闭。任何想法可能是错的？...

方法：

private void setTag(String tag){
WeatherImageDB weatherimagedb = new WeatherImageDB(this); // get logcat error on this line
        weatherimagedb.open();

        ArrayList<String> image_list = new ArrayList<String>();
        image_list.clear();

            if(weatherimagedb.open() != null){
            Cursor cursor = weatherimagedb.retrieveTag(tag);
            Log.d(TAG, "size is " + cursor.getCount()); // this always gets incremented with also the last value added

             if(cursor.moveToFirst()){
                do{
                    image_list.add(cursor.getString(cursor.getColumnIndex(tag)));
                    //System.out.println("imagelisted!!");
                }       
                while(cursor.moveToNext());

                }

                //do other stuffs here with arraylist and then clear

            }
            image_list.clear();
            cursor.close();
            weatherimagedb.close();

        }

和数据库类中的代码：

    private final Context mcontext;
    private DBHelper dbhelper;
    private SQLiteDatabase db;

    public WeatherImageDB(Context context){
        mcontext = context;
        dbhelper = new DBHelper(mcontext);
    }

    public class DBHelper extends SQLiteOpenHelper {

        DBHelper(Context context){
            super(context, IMAGE_DB, null, DATABASE_VERSION);

        }
        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL(DATABASE_CREATE);

        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL("DROP TABLE IF EXISTS imagetags");
            onCreate(db);   
        }       
    }


    public WeatherImageDB open() throws SQLException {
        try{
            db = dbhelper.getWritableDatabase();
        }catch(SQLException e){
            db = dbhelper.getReadableDatabase();
        }
        return this;

    }

    public void close(){
        Log.d(TAG, "calling close on Database Object here");
        if(dbhelper != null){
        dbhelper.close();
        db.close();
        }
    }

    public long tagImage(String pathname, ContentValues val){   
        return db.insert(DATABASE_TABLE, null, val);    
    }

    public boolean deleteTag(String entry ){
        return db.delete(DATABASE_TABLE, null, null) >0;
    }

    public Cursor retrieveTag(String tag){
        //open();
        String[] condition = {tag};
        Cursor cursor = db.query(DATABASE_TABLE, condition, null, null, null, null, null);      
        return cursor;
    }

}

Answer 1

如果只是循环，你声明的游标范围将在内部....我认为可能有一些其他全局对象与“游标”同名......

if(weatherimagedb.open() != null){
    Cursor cursor = weatherimagedb.retrieveTag(tag);
    //some stuff--> make sure there are no return statements in this part.
      //If any return statement  exists close   the cursor and then execute return

    //it should be closed here
    cursor.close(); 
}
//You are closing outside if loop which is holding reference of some other cursor
cursor.close();

游标和数据库没有得到关闭android

1 个答案: