I am working on my storyboards. I have created my main.lua, menu.lua, and game.lua files. I have created a ‘start button’ which loads properly. The button responds to touch, which I verified through a print statement. However, the project oes not transition from the menu.lua to the game.lua file. I recieve the following message:
…uilds\virus3(builds)\virus3(default)\virus3\menu.lua:49: attempt to call field ‘goToScene’ (a nil value)
message
stack traceback:
?: in function <?:218>
[C]: in function ‘goToScene’
…uilds\virus3(builds)\virus3(default)\virus3\menu.lua:49: in function <…uilds\virus3(builds)\virus3(default)\virus3\menu.lua:47>
?: in function <?:218>
Here is a sample of my menu.lua code:
function scene:createScene( event )
local group = self.view
-----------------------------------------------------------------------------
– CREATE display objects and add them to ‘group’ here.
– Example use-case: Restore ‘group’ from previously saved state.
-----------------------------------------------------------------------------
print(“Menu Screen Created”)
local contentWidth = display.contentWidth
local contentHeight = display.contentHeight
local startButton = display.newImageRect(group, “Images/Start-Button.png”, 200, 80 )
startButton.x = contentWidth/2
startButton.y = contentHeight/2
local function onStartTouch(event)
if event.phase==“ended” then
storyboard.goToScene(“game”)
print(“Button Touched!”)
end
end
startButton:addEventListener(“touch”, onStartTouch)
end
Hightlighted is the source of my error.
I placed my code from the Storyboard template undre “Beginning of yout implementation” in the game.lua file.
the game.lua file:
local storyboard = require( “storyboard” )
local scene = storyboard.newScene()
–
– NOTE:
–
– Code outside of listener functions (below) will only be executed once,
– unless storyboard.removeScene() is called.
–
– local forward references should go here –
local screen
local virusColony={}
local gameVars = {}
gameVars.totalVirusesOnScreen = 0
gameVars.maxVirusOnScreen = 20
gameVars.currentLevel = 1
gameVars.currentLevelBeat = false
gameVars.levels = {}
local bgMusic
local bgMusicChannel
local virusPopSound, virusPopSoundChannel
local drawLevel
local function restartGame(event)
if “clicked” == event.action then
local i = event.index
if 1 == i then --retry button
print(“Restarting Level Now”)
for j =1, #virusColony do
if virusColony[j]~=nil then
virusColony[j]:removeSelf()
virusColony[j]=nil
end
end
if gameVars.currentLevelBeat == false then
drawLevel(gameVars.currentLevel)
else
gameVars.currentLevel = gameVars.currentLevel + 1
if gameVars.currentLevel> #gameVars.levels then
--show game end
print(“Game Beat”)
else
drawLevel(gameVars.currentLevel)
end
end
end
end
gameVars.currentLevelBeat = false
end
local function endGame(endGameStatus)
if endGameStatus==“Lost” then
print (“GAME OVER, Too Many Viruses on the Screen”)
for i =1, #virusColony do
--print i,j in pairs(virusColony) do print(i,j) end
local thisVirus = virusColony[i]
if thisVirus ~= nil then
thisVirus:stopMoving()
thisVirus:stopGrowing()
thisVirus:stopRespondingToTouch()
end
end
gameVars.currentLevelBeat = false
native.showAlert( “Dommo app”, “There are too many pics Dommy” , { “Retry” } , restartGame )
elseif endGameStatus==“Won” then
gameVars.currentLevelBeat = true
native.showAlert( “Dommo app”, “Congratulations! You cleared the boneheads!” , { “Continue” } , restartGame )
end
end
local function createVirus(params)
local params = params
local group = params.group or screen
local color = params.color or “Red”
local virusSize
if params.age==2 then
virusSize = 96
elseif params.age== 1 then
virusSize =64
else
virusSize =32
end
local virus = display.newImageRect(group, “/Images/”…color…“Virus.png”, virusSize,virusSize )
virus.age = params.age or 0
virus.x = params.x or display.contentWidth/2
virus.y = params.y or display.contentHeight/2
virus.speed = params.speed or 100
virus.children = params.children or 2
virus.color = color
function virus.move()
local random = math.random
local sqrt = math.sqrt
local minX, maxX, minY, maxY = 10+virus.width/2, 310-virus.width/2, 60+virus.height/2, 470-virus.height/2
local currentX, currentY = virus.x, virus.y
local targetX= random(minX, maxX)
local targetY = random(minY, maxY)
local distance=sqrt((targetY-currentY)^2+(targetX-currentX)^2)
local transitionTime = distance/virus.speed *1000
virus.transition = transition.to( virus, { time=transitionTime, alpha=1, x=targetX, y=targetY, onComplete=virus.move } )
end
virus.move()
function virus.grow()
if virus.age<2 then
virus.width = virus.width +32
virus.height = virus.height +32
virus.age = virus.age + 1
end
end
virus.growTimer = timer.performWithDelay(5000, virus.grow, 2)
function virus:stopGrowing()
timer.cancel(virus.growTimer)
end
function virus:stopMoving()
transition.cancel(virus.transition)
end
function virus:stopRespondingToTouch()
virus:removeEventListener(“touch”, virus)
end
function virus:touch(event)
if event.phase==“ended” then
virus:stopGrowing()
virus:stopMoving()
local event = {name=“virusDied”, target=virus}
virus:dispatchEvent(event)
audio.play(virusPopSound)
end
return true
end
virus:addEventListener(“touch”, virus)
return virus
end
local function checkTotalVirus()
if gameVars.totalVirusesOnScreen>gameVars.maxVirusOnScreen then
local endGameStatus = “Lost”
endGame(endGameStatus)
return true
elseif gameVars.totalVirusesOnScreen==0 then
local endGameStatus = “Won”
endGame(endGameStatus)
return true
end
end
function drawLevel (level)
gameVars.totalVirusesOnScreen = 0
local level = level or 1
local virusType = {
--define the virus types
{[“color”]=“Blue”, [“speed”]=50, [“age”]=2, [“children”]=2},
{[“color”]=“Green”, [“speed”]=75, [“age”]=2,[“children”]=2},
{[“color”]=“Red”, [“speed”]=100, [“age”]=2, [“children”]=2}
}
gameVars.levels = {
{0,0,1}, --level 1
{0,1,0}, --level 2
{1,0,0} --level 3
}
for virusTypes = 1, 3 do
--print (levels[level][virusTypes])
local virusToSpawn = gameVars.levels[level][virusTypes]
for spawns = 1, virusToSpawn do
local params = virusType[virusTypes]
local thisVirus = createVirus(params)
local function killOffVirus(event)
– print(“We just heard a virus died”)
– print(“Before:”)
– for i, j in pairs(virusColony) do print(i,j) end
local copyOfVirus = event.target
local thisVirusIndex = event.target.index
event.target:removeSelf()
event.target = nil
virusColony[thisVirusIndex] = nil
– print(“After:”)
– for i, j in pairs(virusColony) do print(i,j) end
gameVars.totalVirusesOnScreen = gameVars.totalVirusesOnScreen -1
if copyOfVirus.age>0 then
for children = 1, copyOfVirus.children do
local params = {color=copyOfVirus.color, speed=copyOfVirus.speed, age=copyOfVirus.age-1, children=copyOfVirus.children,x=copyOfVirus.x,y=copyOfVirus.y }
local thisVirus = createVirus(params)
thisVirus:addEventListener(“virusDied”, killOffVirus)
thisVirus.index = #virusColony +1
gameVars.totalVirusesOnScreen = gameVars.totalVirusesOnScreen +1
table.insert(virusColony, thisVirus )
if checkTotalVirus()==true then
break
end
end
else
checkTotalVirus()
end
copyOfVirus = nil
end
thisVirus:addEventListener(“virusDied”, killOffVirus)
thisVirus.index = #virusColony +1
gameVars.totalVirusesOnScreen = gameVars.totalVirusesOnScreen +1
table.insert(virusColony, thisVirus )
checkTotalVirus()
end
end
end
local function initScreen()
screen = display.newGroup()
local contentWidth = display.contentWidth
local contentHeight = display.contentHeight
local background = display.newImageRect(screen, “/Images/background.png”, contentWidth, contentHeight )
background.x = contentWidth/2
background.y = contentHeight/2
--Load Music
bgMusic=audio.loadStream(“Sounds/proximity.ogg”)
bgMusicChannel = audio.findFreeChannel()
audio.play(bgMusic, {channel=bgMusicChannel, loops=-1, fadeIn=3000})
--Load Virus Sound
virusPopSound=audio.loadSound(“Sounds/pop.ogg”)
virusPopSoundChannel = audio.findFreeChannel()
drawLevel()
end
– BEGINNING OF YOUR IMPLEMENTATION
– Called when the scene’s view does not exist:
function scene:createScene( event )
local group = self.view
-----------------------------------------------------------------------------
– CREATE display objects and add them to ‘group’ here.
– Example use-case: Restore ‘group’ from previously saved state.
-----------------------------------------------------------------------------
end
– Called BEFORE scene has moved onscreen:
function scene:willEnterScene( event )
local group = self.view
-----------------------------------------------------------------------------
– This event requires build 2012.782 or later.
-----------------------------------------------------------------------------
end
– Called immediately after scene has moved onscreen:
function scene:enterScene( event )
local group = self.view
-----------------------------------------------------------------------------
– INSERT code here (e.g. start timers, load audio, start listeners, etc.)
-----------------------------------------------------------------------------
initScreen()
end
– Called when scene is about to move offscreen:
function scene:exitScene( event )
local group = self.view
-----------------------------------------------------------------------------
– INSERT code here (e.g. stop timers, remove listeners, unload sounds, etc.)
-----------------------------------------------------------------------------
end
– Called AFTER scene has finished moving offscreen:
function scene:didExitScene( event )
local group = self.view
-----------------------------------------------------------------------------
– This event requires build 2012.782 or later.
-----------------------------------------------------------------------------
end
– Called prior to the removal of scene’s “view” (display group)
function scene:destroyScene( event )
local group = self.view
-----------------------------------------------------------------------------
– INSERT code here (e.g. remove listeners, widgets, save state, etc.)
-----------------------------------------------------------------------------
end
– Called if/when overlay scene is displayed via storyboard.showOverlay()
function scene:overlayBegan( event )
local group = self.view
local overlay_name = event.sceneName – name of the overlay scene
-----------------------------------------------------------------------------
– This event requires build 2012.797 or later.
-----------------------------------------------------------------------------
end
– Called if/when overlay scene is hidden/removed via storyboard.hideOverlay()
function scene:overlayEnded( event )
local group = self.view
local overlay_name = event.sceneName – name of the overlay scene
-----------------------------------------------------------------------------
– This event requires build 2012.797 or later.
-----------------------------------------------------------------------------
end
– END OF YOUR IMPLEMENTATION
– “createScene” event is dispatched if scene’s view does not exist
scene:addEventListener( “createScene”, scene )
– “willEnterScene” event is dispatched before scene transition begins
scene:addEventListener( “willEnterScene”, 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 )
– “didExitScene” event is dispatched after scene has finished transitioning out
scene:addEventListener( “didExitScene”, 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 )
– “overlayBegan” event is dispatched when an overlay scene is shown
scene:addEventListener( “overlayBegan”, scene )
– “overlayEnded” event is dispatched when an overlay scene is hidden/removed
scene:addEventListener( “overlayEnded”, scene )
return scene
Any feedback would be greatly appreciated.
CHarpke