EventBus.md

API — EventBus (FT_EventBus)

File: src/core/EventBus.lua
Global: FT_EventBus

Quick-reference. See developer/eventbus.md for usage patterns and implementation notes.

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Methods

FT_EventBus:on(event, fn)

Registers fn as a listener for event. Persists for the game session.

FT_EventBus:off(event, fn)

Removes fn from event. The function reference must match exactly.

FT_EventBus:emit(event, ...)

Calls all listeners for event with ... as arguments. Each listener is wrapped in pcall.

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Well-Known Events

All names are in FT_EventBus.EVENTS:

Constant	String	Arguments	Emitted by
TABLET_OPENED	"tablet_opened"	—	FarmTabletUI:openTablet()
TABLET_CLOSED	"tablet_closed"	—	FarmTabletUI:closeTablet()
APP_SWITCHED	"app_switched"	appId: string	FarmTabletUI:switchApp()
APP_REGISTERED	"app_registered"	appId: string	AppRegistry:register()
SETTINGS_CHANGED	"settings_changed"	—	(reserved)
DATA_REFRESHED	"data_refreshed"	—	(reserved)

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Example

-- Subscribe at mission load time
FT_EventBus:on(FT_EventBus.EVENTS.TABLET_OPENED, function()
    -- refresh your mod's state here
end)

FT_EventBus:on(FT_EventBus.EVENTS.APP_SWITCHED, function(appId)
    if appId == "my_app" then
        -- user just switched to my app
    end
end)