"Table index is nil"

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1

I'm trying to use LDtk entity referrals so that I can link a button to another entity and have it call an activate() script on that entity. To test, I just added a door that opens when Door:activate() is called, and added

elseif entityName == "Door" then
            local door = Door(entityX, entityY, "door")
            self.buttonEntities[door.entityIid] = door
        elseif entityName == "Button" then
            local button = Button(entityX, entityY, entity, self, "button", "door")
            self.buttonEntities[button.entityIid] = button
        end

to where I add the LDtk entities, and

    self.buttonEntities = {}

at the top of the file. Then, in the button script, I have

local pd <const> = playdate.graphics
local gfx <const> = playdate.graphics

import "scripts/player"
import "scripts/gameScene"
import "CoreLibs/animator"
import "CoreLibs/graphics"

class('Button').extends(AnimatedSprite)

function Button:init(x, y, entity, gameManager, entityIid, linkedObjectIid)
    self.pressed = false
    self.fields = entity.fields
    self.direction = self.fields.Direction
    self.floor = 1
    self.gameManager=gameManager;
    self.entities = self.gameManager.entities

    self.entityIid = entityIid
    self.linkedObjectIid = linkedObjectIid

    local buttonImageTable = gfx.imagetable.new("images/button-table-20-40")
    Button.super.init(self, buttonImageTable)
    self:addState("Default", 1, 2, {tickStep = 10})
    self:addState("Pressed", 2, 6, {loop = false})
    self:playAnimation()
    self:setZIndex(Z_INDEXES.Button)
    self:setCenter(0, 0)
    self:moveTo(x, y)
    self:add()

    self:setTag(TAGS.Button)
    self:setCollideRect(0, 0, self:getSize())
    self.collisionResponse = "bounce"
end

function Button:pickUp(player)
    if self.pressed == false then
        local object = self.entities[self.linkedObjectIid]
        if object then
            object:activate()
        end
        self:changeState("Pressed")
        self.pressed = true
        self:setCollideRect(16, 0, 4, 20)
    end
end

But when I build and run, I get

Table index is nil

In the line that calls

self.buttonEntities[door.entityIid] = door

(And yes, everything is set up right in LDtk)

2

Sorry, my bad I forgot to put

self.entityIid = entityIid

in the door script