removing eventListener in another function

Solar2D General Questions/Discussion
#1

I’m facing a challenge with eventListeners in several of my functions. Here is a simplified example:

local function exitOverlayMode( event )    composer.hideOverlay()    -- Hides the overlay (re-enable underneath content)  if( globalData.backgroundRectangleOverlay ~= nil ) then      globalData.backgroundRectangleOverlay:removeSelf()         globalData.backgroundRectangleOverlay = nil              end    -- Do some more stuff   return true   -- Prevents propagating the event to other objects    end   -- exitOverlayMode

local function upgradeLevel( event )      exitOverlayMode()   -- Exiting the overlay and re-enable some in-game functions   -- Do stuff to upgrade the building end

-- Overlay scene function create( event )   local upgradeBlockArea = display.newRoundedRect(100, 100, 400, 200, 60 )   upgradeBlockArea:addEventListener("tap", upgradeLevel)  -- Starts listening to tap on the upgradeBlockArea end   -- "scene:create()"

In my scene:create() I have a rectangle area acting as a button, which will call the upgradeLevel function when the user taps the area. For that I create the  addEventListener on  upgradeBlockArea.

In the  upgradeLevel , I would like to remove the EventListener on  upgradeBlockArea (because I have read that it is best practice) and the only way to do that  is to change my code and using pseudo global variable. For that I would add the EventListenaer and remove it as follows:

-- In overlay scene globalData.upgradeBlockArea:addEventListener("tap", upgradeLevel)

-- In upgrade function globalData.upgradeBlockArea:removeEventListener("tap", upgradeLevel)

Is that the only/best way to do it? Any recommendation? Is it necessary to always remove event listeners, even in an overlay ?

#2

Where is upgradeLevel? If in the same file as create, you can just store upgradeBlockArea as a local variable in the file, instead of local to the create function. Then upgradeBlockArea is accessible from upgradeLevel.

#3

Good suggestion, in that specific case upgradeLevel and upgradeBLockArea are in the same file so that would work.

For cases where they are in different files, is there a better to do than my suggestion?

#4

Where is upgradeLevel? If in the same file as create, you can just store upgradeBlockArea as a local variable in the file, instead of local to the create function. Then upgradeBlockArea is accessible from upgradeLevel.

#5

Good suggestion, in that specific case upgradeLevel and upgradeBLockArea are in the same file so that would work.

For cases where they are in different files, is there a better to do than my suggestion?