Maintenance script: UI Lua API import (WAR 1.4.8)

2026-10-16T19:40:57Z

UI Lua API import (WAR 1.4.8)

New page

{{LuaApi|group=Crafting}}
Asks the trainer the player is talking to for a trade skill, optionally giving up another one.

<pre>
BuyTradeSkill(tradeSkill, skillToDiscard)
</pre>

== Arguments ==
;tradeSkill : <code>number</code> – The trade skill to learn, as a <code>GameData.TradeSkills</code> value (1 = <code>BUTCHERING</code> … 6 = <code>SALVAGING</code>). The stock UI passes <code>GameData.InteractData.trainerTradeSkill</code>.
;skillToDiscard : <code>number</code> – A trade skill the player gives up to make room, or 0 for none.

== Returns ==
Nothing.

== Details ==
* Both values are sent as single bytes together with the id of the current interaction (the trainer the player is talking to).
* The client does not check the values. Which skills conflict is worked out by the stock UI (<code>EA_Window_InteractionTraining.GetConflictingTradeSkill</code>), and the server decides whether the purchase is allowed.
* The function needs at least two arguments and only reads the last two.

== Errors ==
None besides the generic ''Invalid Parameters'' message when an argument is not a number.

== Example ==
From <code>default/ea_interactionwindow/source/interactiontradeskills.lua</code>:
<pre>
function EA_Window_InteractionTraining.DiscardTradeSkillAndBuyAnother()
BuyTradeSkill( GameData.InteractData.trainerTradeSkill, EA_Window_InteractionTraining.ConflictingSkill )
PlayInteractSound("trainer_accept")
end

function EA_Window_InteractionTraining.BuyTradeSkill()
BuyTradeSkill( GameData.InteractData.trainerTradeSkill, 0 )
PlayInteractSound("trainer_accept")
end
</pre>

== See also ==
* [[API:GetTradeSkillLevel|GetTradeSkillLevel]]
* [[API:BuyCareerPackage|BuyCareerPackage]]

API:BuyTradeSkill - Revision history

Maintenance script: UI Lua API import (WAR 1.4.8)