Corona SDK gotoScene 错误

Question

所以我在 Corona SDK 中制作了一个应用程序，当我单击试图加载我的第一级的按钮时出现错误。

这是我的代码：

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 个代码

我得到的错误是这样的：

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.

感谢阅读，希望你能找到答案，因为我找不到：)

Answer 1

问题是您的 level1.lua 中确实有 0 代码。我将向您发送这个每个人第一次开始使用故事板时都会使用的模板代码。

您的代码的问题是，当您进入关卡 1 时，没有创建场景的代码。此外，没有关于场景何时进入、退出或被破坏的代码。这样一来，您在 menu.lua 上的代码就无处可去。将下面的代码复制粘贴到第 1 级。当我使用场景模板运行您的代码时，它对我有用。

另一方面，我注意到您的函数和显示对象是在 createScene 中创建的。我会将它们放在 enterScene 中，因为它们只能在页面加载后调用。

希望这会有所帮助！如果您的代码不起作用或有其他问题，请与我联系。

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

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

首先检查你在listener，level1，about中编写的所有lua文件，并且它的名称应该相同并且适当区分大小写。

你的level1.lua会有问题，应该不是代码。

如果你想用 0 代码的故事板来实现它。请确保您已在顶部实现了故事板对象，并且其场景从底部正确返回。

喜欢：

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

--你的level1.lua的最后一行

return scene

Answer 3

马修是对的。跟随他的脚步。 我只是想添加一个您可能会发现有用的未来提示。调试错误代码时，如果代码状态为全局（零值），则表示某些内容为空，即如果没有任何内容，则无法调用对象。和？ in function 表示包含空值的特定对象或函数。如果您再次看到此错误，请检查拼写错误。