swapping inventory item

//if the slot got an item
        else if (draggingItem.slot != slotID)
        {
            //get the slot that currently have item
            ItemDragHandler thisSlotItem = this.transform.GetChild(0).GetComponent<ItemDragHandler>(); //the only things in slot
            thisSlotItem.slot = draggingItem.slot; // 3->2 DIS
            thisSlotItem.transform.SetParent(inv2.slots[draggingItem.slot].transform);
            thisSlotItem.transform.position = inv2.slots[draggingItem.slot].transform.position;

            //changing the item drag to current slot that have been pointed
            draggingItem.slot = slotID; // 2->3 DIS
            draggingItem.transform.SetParent(this.transform);
            draggingItem.transform.position = this.transform.position;

            //zzzz the item swap wrong becoz the slot is edy change in the first place ==
            inv2.items[thisSlotItem.slot] = thisSlotItem.item;
            inv2.items[draggingItem.slot] = draggingItem.item;


        }