Changing Scenes in Corona objects stay on screen - lua

Question

I have been modifying code from the memory match game to use scenes, sounds, and a 2d table. Adding the scenes has been the hard part. I have it set up to randomly select items from my 2d table. Load those into a temporary table, shuffle them shuffle(), then boardSet(); to load their sounds and place them on the screen. Basically after the game is over I want the scene to reload or go back to the menu to start again. Selecting random data{} elements over and over.
I have tried returning to the menu, or going to a duplicate scene however I can't seem to correctly unload the objects created by my 2d array, as I can't properly add each item into a display group. I have tried everything I can think of. Right now my game loop is setup to add the play again btn that I want to restart the game after one match is found.
This link was a start in the right direction I believe with information about dealing with tables and groups. I still don't know how to cycle thru my 2d table to include everything in a group and then properly unload it.
http://developer.coronalabs.com/content/application-programming-guide-graphics-and-drawing#Variable_References
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--
-- level1.lua
--
---------------------------------------------------------------------------------
local storyboard = require( "storyboard" )
local scene = storyboard.newScene()
local widget = require "widget"
---------------------------------------------------------------------------------
-- BEGINNING OF YOUR IMPLEMENTATION
---------------------------------------------------------------------------------
local image, text1, text2, text3, memTimer
-- forward declarations and other locals
local againBtn
-- 'onRelease' event listener for playBtn
local function onPlayBtnRelease()
-- go to level1.lua scene
storyboard.gotoScene( "menu", "fade", 500 )
return true -- indicates successful touch
end
-- Preload the sound file (needed for Android)
--
local playBeep = function( testSound )
media.playEventSound( testSound )
end
---Preload sounds
ki = audio.loadSound("ki-nawaneyoo.mp3")
u = audio.loadSound("u.mp3")
mayuhoo = audio.loadSound("mayuhoo.mp3")
--End Sound Test
--Set Global width and height variables
_W = display.contentWidth;
_H = display.contentHeight;
---Count number of correct matches
local matchCount = 0;
--Hide status bar
display.setStatusBar(display.HiddenStatusBar);
--Declare a totalButtons variable to track number of buttons on screen
local totalButtons = 0
--Declare variable to track button select
local secondSelect = 0
local checkForMatch = false
--Declare Data Table
local data = {}
--Load objects into data
data[1] = {}
data[1].title = "Naka"
data[1].subtitle = "a"
data[1].image = "a.png"
data[1].image1 = "ear.png"
data[1].sound = "naka-ear.caf"
data[1].sound1 = "naka-ear.mp3"
data[2] = {}
data[2].title = "Aapuhu"
data[2].subtitle = "aa"
data[2].image = "aa.png"
data[2].image1 = "eyebrow.png"
data[2].sound = "aapuhu-eyebrow.caf"
data[2].sound1 = "aapuhu-eyebrow.mp3"
data[3] = {}
data[3].title = "Ego"
data[3].subtitle = "Ego"
data[3].image = "e.png"
data[3].image1 = "tongue.png"
data[3].sound = "ego-tongue.caf"
data[3].sound1 = "ego-tongue.mp3"
data[4] = {}
data[4].title = "Kamoo"
data[4].subtitle = "kamoo"
data[4].image = "ee.png"
data[4].image1 = "chin.png"
data[4].sound = "kamoo-chin.caf"
data[4].sound1 = "kamoo-chin.mp3"
data[5] = {}
data[5].title = "Kowpa"
data[5].subtitle = "ego"
data[5].image = "leg.png"
data[5].image1 = "leg.png"
data[5].sound = "kowpa-leg.caf"
data[5].sound1 = "kowpa-leg.mp3"
data[6] = {}
data[6].title = "Mae"
data[6].subtitle = "kwa"
data[6].image = "hand.png"
data[6].image1 = "hand.png"
data[6].sound = "mae-hand.caf"
data[6].sound1 = "mae-hand.mp3"
data[7] = {}
data[7].title = "Nodo"
data[7].subtitle = "kwe"
data[7].image = "kwe.png"
data[7].image1 = "throat.png"
data[7].sound = "nodo-throat.caf"
data[7].sound1 = "nodo-throat.mp3"
data[8] = {}
data[8].title = "Matogo"
data[8].subtitle = "kwe"
data[8].image = "kwe.png"
data[8].image1 = "thumb.png"
data[8].sound = "matogo-thumb.caf"
data[8].sound1 = "matogo-thumb.mp3"
data[9] = {}
data[9].title = "Matzehe"
data[9].subtitle = "kwe"
data[9].image = "kwe.png"
data[9].image1 = "elbow.png"
data[9].sound = "matzehe-eblow.caf"
data[9].sound1 = "matzehe-elbow.mp3"
data[10] = {}
data[10].title = "Kuku"
data[10].subtitle = "kwe"
data[10].image = "kwe.png"
data[10].image1 = "foot.png"
data[10].sound = "kuku-foot.caf"
data[10].sound1 = "kuku-foot.mp3"
--Declare button, buttonCover, and buttonImages table
local tableCopy = {}
local buttonImages = {}
--Shuffle data table
--local shuffleSet = function()
--Shuffle data table
math.randomseed (os.time())
local function shuffle(a)
local n = #a
local t
local k
while(n > 0) do
t = a[n]
k = math.random(n)
a[n] = a[k]
a[k] = t
n = n - 1
end
return a
end
local tableCopy = shuffle(data);
local button = {}
local buttonCover = {}
--Choose six random objects from data to be used in game.
local firstSix = {}
for i = 1,6 do
firstSix[i] = tableCopy[i];
end
local buttonImages = {firstSix[1],firstSix[1],firstSix[2],firstSix[2],firstSix[3],firstSix[3],firstSix[4],firstSix[4],firstSix[5],firstSix[5],firstSix[6],firstSix[6]}
--end
--Declare and prime a last button selected variable
local lastButton;-- = display.newImage("1.png");
--lastButton.myName = 1;
--
--Set up simple off-white background
--Notify player if match is found or not
local matchText = display.newText(" ", 0, 0, native.systemFont, 65)
matchText:setReferencePoint(display.CenterReferencePoint)
matchText:setTextColor(255, 255, 255)
matchText.x = _W/2
--
--Set starting point for button grid
local x = -20
local matchesFound = 0;
--Set up game function
local function game(object, event)
if(event.phase == "began") then
if(checkForMatch == false and secondSelect == 0) then
--Flip over first button
buttonCover[object.number].isVisible = false;
audio.play(object.sound);
lastButton = object
checkForMatch = true
elseif(checkForMatch == true and object.number ~= lastButton.number) then
if(secondSelect == 0) then
--Flip over second button
buttonCover[object.number].isVisible = false;
secondSelect = 1;
--If buttons do not match, flip buttons over
if(lastButton.myName ~= object.myName) then
audio.play(object.sound);
timer.performWithDelay(1000,function()
matchText.text = "Ki Nawa'neyoo";
audio.play(ki); end,1)
timer.performWithDelay(2500, function()
matchText.text = " ";
checkForMatch = false;
secondSelect = 0;
buttonCover[lastButton.number].isVisible = true;
buttonCover[object.number].isVisible = true;
end, 1)
--If buttons DO match, remove buttons
elseif(lastButton.myName == object.myName) then
matchText.text = "U " .. object.myName .. " Mayuhoo";
audio.play(u)
timer.performWithDelay(750,function()
audio.play(object.sound); end, 1)
timer.performWithDelay(1500,function()
audio.play(mayuhoo); end, 1)
timer.performWithDelay(2400, function()
matchText.text = " ";
checkForMatch = false;
secondSelect = 0;
lastButton:removeSelf();
object:removeSelf();
buttonCover[lastButton.number]:removeSelf();
buttonCover[object.number]:removeSelf();
matchesFound = matchesFound + 1;
timer.performWithDelay(250, function()
if (matchesFound == 1) then
matchText.text = " Play Again? ";
againBtn.isVisible = true;
-- all display objects must be inserted into group
--group:insert( playBtn )
end
end, 1)
end, 1)
end
end
end
end
end
--]]
-- Touch event listener for background image
--[[
local function onSceneTouch( self, event )
if event.phase == "began" then
storyboard.gotoScene( "scene2", "slideLeft", 800 )
return true
end
end
--]]
-- Called when the scene's view does not exist:
function scene:createScene( event )
local screenGroup = self.view
local image = display.newImageRect( "bg.png", display.contentWidth, display.contentHeight )
image:setReferencePoint( display.TopLeftReferencePoint )
image.x, image.y = 0, 0
screenGroup:insert( image )
local function boardSet()
for count = 1,3 do
x = x + 100 * 2
y = 20 *2
for insideCount = 1,4 do
y = y + 90 * 2
--Assign each image a random location on grid
local temp = math.random(1,#buttonImages)
button[count] = display.newImageRect(buttonImages[temp].image1, 150, 150);
--Position the button
button[count].x = x;
button[count].y = y;
--Give each a button a name
button[count].myName = buttonImages[temp].title
-- Preload the sound file (needed for Android)
--Give each button a sounds
soundID = audio.loadSound(buttonImages[temp].sound1)
button[count].sound = soundID
button[count].sound1 = soundID
button[count].number = totalButtons
--Remove button from buttonImages table
table.remove(buttonImages, temp)
--Set a cover to hide the button image
buttonCover[totalButtons] = display.newImageRect("button.png", 150, 150);
buttonCover[totalButtons].x = x; buttonCover[totalButtons].y = y;
--screenGroup:insert(button[count].)
totalButtons = totalButtons + 1
--Attach listener event to each button
button[count].touch = game
button[count]:addEventListener( "touch", button[count] )
end
end
end
boardSet();
end
-- Called immediately after scene has moved onscreen:
function scene:enterScene( event )
againBtn = widget.newButton{
label="Play Again?",
fontSize = 25,
labelColor = { default={255}, over={128} },
default="button1.png",
over="button-over.png",
width=250, height=100,
onRelease = onPlayBtnRelease -- event listener function
}
againBtn:setReferencePoint( display.CenterReferencePoint )
againBtn.x = display.contentWidth * 0.5
againBtn.y = display.contentHeight - 125
againBtn.isVisible = false
print( "1: enterScene event" )
-- remove previous scene's view
end
-- Called when scene is about to move offscreen:
function scene:exitScene( event )
print( "1: exitScene event" )
if againBtn then
matchText.text = " "
againBtn:removeSelf() -- widgets must be manually removed
button = nil
buttonCover = nil
firstSix = nil
data = nil
tableCopy = nil
buttonImages = nil
againBtn = nil
end
end
-- Called prior to the removal of scene's "view" (display group)
function scene:destroyScene( event )
local screenGroup = self.view
storyboard.removeScene();
--storyboard.purgeScene( "level1" )
print( "((destroying scene 1's view))" )
end
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-- END OF YOUR IMPLEMENTATION
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-- "createScene" event is dispatched if scene's view does not exist
scene:addEventListener( "createScene", scene )
-- "enterScene" event is dispatched whenever scene transition has finished
scene:addEventListener( "enterScene", scene )
-- "exitScene" event is dispatched before next scene's transition begins
scene:addEventListener( "exitScene", scene )
-- "destroyScene" event is dispatched before view is unloaded, which can be
-- automatically unloaded in low memory situations, or explicitly via a call to
-- storyboard.purgeScene() or storyboard.removeScene().
scene:addEventListener( "destroyScene", scene )
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return scene

Answer 1

Yeah, this is simple.
here is an example(assuming that you have implemented storyboard)
function scene:createScene(event)
screenGroup = self.view
local image = display.newImage("image.png")
screenGroup:insert(image)
end
Now everything will go fine :)

Answer 2

Add all the display objects to a group.local myGroup = display.newGroup();
local img = display.newImage("yourimage.png");
myGroup:insert(img);
For example
If you follow this method, all display objects will not be flushed out of memory when you change the screen.

Answer 3

When using corona storyboard you need to add display objects to the group. For example you would need to add all of your display objects into screenGroup in order for them to be removed when you change scenes.