local and global function by external module

Getting Started Newbie Questions
#1

Hi guys.
I’ve a problem with external modules. How can i call a local function by external module?

Example.
I have some buttons in an external module and the button function in main.lua . When the function is global it is called, but when it is local the buttons don’t see it . How can i do to solve?

#2

Assuming I’ve understood the question correctly, if you have a local function in a module then it will only be  visible to that module. If you have a local function that you want to expose you could do something like this.

buttons.lua:

local buttons = {} local function myPrivateFunction() -- this is only visible in this module end function buttons.myPublicFunction() -- this will be accessible via the returned buttons table end return buttons

main.lua

local buttons = require("buttons") -- we can now call the function buttons.myPublicFunction()
1 Like
#3

Maybe this post will help clarify. It’s a bit old but still valid.

http://coronalabs.com/blog/2012/08/28/how-external-modules-work-in-corona/

#4

No. My question is different.

I’ve something like this

–main lua
local but = require “buttons”
but.button()
local function handlebuttonevent
– function activate by buttons in module
end

–buttons.lua
local buttons = {}
local function buttons.button()
–widget buttons who call local handlebuttonevent in main
end
Return buttons

If i insesrt local in function handlebuttonevent it doesn’t call. If the function is global it is called normally.

#5

buttons.lua will not be able to see the function handlebuttonevent in main.lua because that function is local to main.lua. You could pass it into the button like this:

-- main.lua local function handlebuttonevent() -- function activated by buttons in module end local but = require "buttons" but.button(handlebuttonevent) -- buttons.lua local buttons = {} function buttons.button(handlebuttonevent) -- this can now call handlebuttonevent end
#6

Thanks for help
the local function run :slight_smile:

#7

Assuming I’ve understood the question correctly, if you have a local function in a module then it will only be  visible to that module. If you have a local function that you want to expose you could do something like this.

buttons.lua:

local buttons = {} local function myPrivateFunction() -- this is only visible in this module end function buttons.myPublicFunction() -- this will be accessible via the returned buttons table end return buttons

main.lua

local buttons = require("buttons") -- we can now call the function buttons.myPublicFunction()
#8

Maybe this post will help clarify. It’s a bit old but still valid.

http://coronalabs.com/blog/2012/08/28/how-external-modules-work-in-corona/

#9

No. My question is different.

I’ve something like this

–main lua
local but = require “buttons”
but.button()
local function handlebuttonevent
– function activate by buttons in module
end

–buttons.lua
local buttons = {}
local function buttons.button()
–widget buttons who call local handlebuttonevent in main
end
Return buttons

If i insesrt local in function handlebuttonevent it doesn’t call. If the function is global it is called normally.

#10

buttons.lua will not be able to see the function handlebuttonevent in main.lua because that function is local to main.lua. You could pass it into the button like this:

-- main.lua local function handlebuttonevent() -- function activated by buttons in module end local but = require "buttons" but.button(handlebuttonevent) -- buttons.lua local buttons = {} function buttons.button(handlebuttonevent) -- this can now call handlebuttonevent end
#11

Thanks for help
the local function run :slight_smile: