Corona SDK GotoScene錯誤

Question

因此，我在Corona SDK中制作了一個應用程序，當我單擊嘗試加載我的第一個級別的按鈕時遇到錯誤。

這是我的代碼：

main.lua

local storyboard = require "storyboard"
storyboard.gotoScene("menu")

menu.lua

local storyboard = require ("storyboard")
local scene = storyboard.newScene()

function scene:createScene( event )

    local screenGroup = self.view

    -- Background
    bg = display.newImage("images/bg.png")
    bg.x = display.contentCenterX
    bg.y = display.contentCenterY
    screenGroup:insert(bg)

    -- Title
    title = display.newImage("images/title.png")
    title.x = display.contentCenterX
    title.y = display.contentCenterY - 100
    screenGroup:insert(title)

    -- Play game
    play = display.newImage("images/playgame.png")
    play.x = display.contentCenterX - 170
    play.y = display.contentCenterY - 27
    screenGroup:insert(play)

    -- About Us
    about = display.newImage("images/about.png")
    about.x = display.contentCenterX - 100
    about.y = display.contentCenterY + 40
    screenGroup:insert(about)

    -- Level Select
    select = display.newImage("images/select.png")
    select.x = display.contentCenterX
    select.y = display.contentCenterY + 100
    screenGroup:insert(select)

end

function start(event)
    if event.phase == "began" then
        storyboard.gotoScene("level1", "fade", 400)
    end
end

function start2(event)
    if event.phase == "began" then
        storyboard.gotoScene("about", "fade", 400)
    end
end

function start3(event)
    if event.phase == "began" then
        storyboard.gotoScene("selectlvl", "fade", 400)
    end
end

function scene:enterScene(event)

    play:addEventListener("touch", start)
    about:addEventListener("touch", start2)
    select:addEventListener("touch", start3)

end

scene:addEventListener( "createScene", scene )
scene:addEventListener( "enterScene", scene )

return scene

我的level1.lua中有0個代碼

我得到的錯誤是這樣的：

Runtime error
    ?:0: attempt to concatenate global 'sceneName' (a nil value)
stack traceback:
    [C]: ?
    ?: in function 'gotoScene'
    ...s\corona projects\stickman obsticale course\menu.lua.42: in function
<...s\corona projects\stickman obsticale course\menu.

感謝您的閱讀，希望您能找到答案，因為我不能:)

Answer 1

問題是您的level1.lua中確實有0個代碼。 我將向您發送此模板代碼，以供大家在初次使用情節提要時使用。

代碼的問題在於，當您進入1級時，沒有任何代碼可以創建場景。 而且，沒有有關場景何時進入，退出或被破壞的代碼。 這樣，menu.lua上的代碼就無處可尋。 將下面的代碼復制粘貼到級別1中。當我使用場景模板運行您的代碼時，它對我有用。

另一方面，我注意到您的函數和顯示對象是在createScene中創建的。 我將它們放在enterScene中，因為只有在頁面加載后才應調用它們。

希望這可以幫助！ 如果您的代碼無法使用或遇到其他問題，請與我聯系。

----------------------------------------------------------------------------------

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.
-- 
---------------------------------------------------------------------------------

---------------------------------------------------------------------------------
-- 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 immediately after scene has moved onscreen:
function scene:enterScene( event )
    local group = self.view

    print("entered")

    -----------------------------------------------------------------------------

    --  INSERT code here (e.g. start timers, load audio, start listeners, etc.)

    -----------------------------------------------------------------------------

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 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

---------------------------------------------------------------------------------
-- END OF YOUR IMPLEMENTATION
---------------------------------------------------------------------------------

-- "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 )

---------------------------------------------------------------------------------

return scene

Answer 2

首先，檢查您在偵聽器level1中編寫的所有lua文件，關於它們的名稱應相同，並且大小寫敏感。

您的level1.lua中將存在問題，並且不應進行編碼。

如果要使用帶有0代碼的情節提要實現它。 請確保已在頂部實現了情節提要對象，並且其場景從底部正確返回。

喜歡：

--Top
local storyboard = require( "storyboard" )
local scene = storyboard.newScene()

-您的level1.lua的最后一行

return scene

Answer 3

馬修是對的。 跟着他走。 我只是想添加一個將來的提示，可能會對您有所幫助。 當調試錯誤代碼時，如果代碼聲明了全局值（nil值），則表示內容為空，如果沒有內容，則無法調用對象。 和？ 函數中的in表示包含空值的特定對象或函數。 如果再次出現此錯誤，請檢查拼寫錯誤。