WoW API type: BagId
While dealing with container and inventory items, many developers use a bag/slot couple and set bag to -1 for the case of an inventory item. But a problem occurs when the bank is opened (after BANKFRAME_OPENED event being fired) because the 28 slots of the bank count as actual container slots with -1 as bagID. In the same idea, items in the bank bags can be accessed via container item functions (like GetContainerItemLink(bagID, slotID), PickupContainerItem(bagID, slotID)) with 5 as bagID for the first bank bag, 6 for the second ... until 11 for the seventh.
To sum up, the current possibilities for bagID are :
- 0 for the backpack
- 1 to 4 for the bags on the character (numbered right to left)
- -2 for the keyring
While the bank is opened:
- -1 for the bank content
- 5 to 11 for bank bags (numbered left to right, was 5-10 prior to 2.0)
How you should code
You should not assume fixed numbers when there are named constants to use. Access your bags according to the following scheme:
- 0 is your backpack
- 1 to NUM_BAG_SLOTS are your bags (NUM_BAG_SLOTS defined in FrameXML\BankFrame.lua, line 2)
- KEYRING_CONTAINER is the keyring
While the bank is opened:
- BANK_CONTAINER is the bank window
- NUM_BAG_SLOTS+1 to NUM_BAG_SLOTS+NUM_BANKBAGSLOTS are your bank bags
This follows the way FrameXML works. Future changes to APIs are less likely to make your addon break if you follow it.