Corona: extends Group example

group.lua

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--
-- extends Group example
--
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local group = {}
local group_mt = { __index = group }	-- metatable

-------------------------------------------------
-- PRIVATE FUNCTIONS
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-------------------------------------------------
-- PUBLIC FUNCTIONS
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function group.new(params)	-- constructor
	
	local newGroup = display.newGroup()
	
	local _group = newGroup

	for k,v in pairs(params) do
		_group[k]=v
	end
	
	local newGroup = {}

	local group_mt = {
		__index = function (t,k)
			if(_group[k]) then
				return _group[k]
			else
				return group[k]
			end
		end,

		__newindex = function (t,k,v)
			if(_group[k]) then
				_group[k] = v
				group[k] = v
			else
				_group[k] = v
				group[k] = v
			end
		end

	}
	newGroup._proxy = _group._proxy
	newGroup._userdata = _group._userdata
	
	setmetatable( newGroup, group_mt )
	
	return newGroup
end

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-- This is just example of how to create custom 
-- OOP functions for all your display object.

function group:hello(target)
	print( self.name .. " say hello to ", target.name )
end

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return group