APE/ui_scripts/ui_collection.lua

-- undrawable container element
-- you can hold stuff in it, strings, numbers, tables, userdata etc
-- has simple adding, deleting and getting interface
-- UIManager's version of an array

Collection = {}
Collection.__index = Collection
Collection.ident = "ui_collection"
Collection.name = "Collection"
Collection.updateable = false
Collection.input = false
Collection.drawable = false
function Collection:new(name)
	local self = {}
	setmetatable(self,Collection)
	self.items = {}
	if name ~= nil then self.name = name end
	return self
end
setmetatable(Collection,{__index = Element})


-- adds element into collection and fires onadd event
function Collection:addItem(item)
	table.insert(self.items,item)
	self:onadd()
end


-- if element is a table or userdata, you will receive a reference to it, in other cases you will create duplicate of that element in your variable
function Collection:getItem(index)
	return self.items[index]
end

function Collection:deleteItem(index)
	table.remove(self.items,index)
	self:ondelete()
end

-- clears collection of anything
function Collection:purge()
	for k,v in pairs(self.items) do self.items[k] = nil end
end

function Collection:getCount()
	return #self.items
end

function Collection:onadd() end
function Collection:ondelete() end


-- UIManager will try to update this collection, you should declare what should it do on every tick,
--[[
	local collection = Collection:new("UColl")
	function collection:update(dt)
		.. do stuff
	end
]]
-- otherwise it will do nothing

UpdateableCollection = {}
UpdateableCollection.__index = UpdateableCollection
UpdateableCollection.ident = "ui_updateablecollection"
UpdateableCollection.name = "UpdateableCollection"
UpdateableCollection.updateable = true
UpdateableCollection.input = false
UpdateableCollection.drawable = false
function UpdateableCollection:new(name)
	local self = {}
	setmetatable(self,UpdateableCollection)
	self.items = {}
	return self
end
setmetatable(UpdateableCollection,{__index = Collection})


function UpdateableCollection:update(dt)
	local c = self:getCount()
	if c>0 then
		for i=1,c do
			self.items[i]:update(dt)
		end
	end
end