Lua 中的条件分支无缘无故不起作用？

Question

我加入这个社区是因为它看起来很棒，而且我是一名新的编码员，所以我想按照这样一个不错的社区的建议尝试并快速改进。 :)

我对 lua 中的编码有疑问 -- 现在，我正在使用 Corona SDK 和 Sublime Text 3 来编写移动启动画面和标题画面的代码。我从 titleScreen = false 开始，这样我就可以运行启动画面的代码，使其变为 true。但是，当我完成运行启动画面的代码并使 titleScreen = true 时，标题画面的条件分支不起作用！请帮助我 :( 我做了很多测试，但无法找出我的错误所在。

这是我的代码：

titleScreen = false
local logo = display.newImage("logo.png", 155, 275)
logo.alpha = 0

local function makeMenuTrue()
    logo:removeSelf()
    print("menu should be TRUE")
    print("WHY DOESN'T IT WORK")
    titleScreen = true  
end

local function fadeOut()
    transition.to(logo, {time = 2000, alpha = 0, onComplete = makeMenuTrue})
end

transition.to(logo, {time = 2000, alpha = 1, onComplete = fadeOut})

if (titleScreen == true) then
    print("NOW IT'S TRUE")
    local mainTheme = audio.loadSound ("mainTheme.wav")
    audio.play(mainTheme)

    display.setStatusBar(display.HiddenStatusBar)
    local background1 = display.newImage("Title.png", 155, 275)

    local flare = display.newImage("flare2.png", 40, 30)
    flare.xScale = .5
    flare.yScale = .5
    local flare2 = display.newImage("flare2.png", 400, 70)
    flare2.xScale = .6
    flare2.yScale = .6
    local flare3 = display.newImage("flare2.png", 400, 70)
    flare2.xScale = .4
    flare2.yScale = .4

    local function moveFlare1() 
        transition.to(flare, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare1})
    end
    local function moveFlare2()
        transition.to(flare2, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare2})
    end 
    local function moveFlare3()
        transition.to(flare3, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare3})
    end 

    transition.to(flare, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare1})
    transition.to(flare2, {time=2500, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare2}) 
    transition.to(flare3, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare3}) 

--[[local textbox = display.newRect(160, 214, 320, 90)
textbox:setFillColor(.1, .1, .1, .6)
]]

    local textbox = display.newImage("MessageBack2.png", 155, 254, 320, 90)
    textbox.yScale = .7
    local textline = display.newImage("flare2.png", 0, 228)
    textline.xScale = 20
    textline.yScale = .3
    local textOption = 1

    local prompt1 = display.newText ("Start Game", 155, 230, "Goudy Old Style", 20)
    local prompt2 = display.newText ("Continue", 155, 255, "Goudy Old Style", 20)
    local prompt3 = display.newText ("Exit Game", 155, 280, "Goudy Old Style", 20)
    prompt1:setFillColor(0,0,0)

    local function textShrink()
        transition.to(textline, {time = 150, yScale = .3})
    end

    local function moveTextBox()
        if (textOption == 1) then
            textOption = 2 
            transition.to(textline, {time = 200, y = 253, onComplete = textShrink})
            prompt2:setFillColor(0,0,0)
            prompt1:setFillColor(1,1,1)
        else 
            if (textOption == 2) then
                textOption = 3
                transition.to(textline, {time = 200, y = 278, onComplete = textShrink})
                prompt3:setFillColor(0,0,0)
                prompt2:setFillColor(1,1,1)
            else 
                if (textOption == 3) then 
                    textOption = 1
                    transition.to(textline, {time = 200, y = 228, onComplete = textShrink})
                    prompt1:setFillColor(0,0,0)
                    prompt3:setFillColor(1,1,1)
                end
            end
        end
    end

    local function expandText()
        if (textOption == 1 ) then
            print("object 1 has been tapped????")
        else 
            if (textOption == 2) then
                print("object 2 has been tapped????")
            else 
                if (textOption == 3) then
                    print("object 3 has been tapped????")
                end
            end
        end
    end

    transition.to(textline, {time = 150, yScale = .5, 0, onComplete = moveTextBox})
    textbox:addEventListener("tap", expandText)
    else 
        print("lmao no it's not true")
    end

非常感谢任何帮助！！

Answer 1

在您将 titleScreen 设置为 false 后对 titleScreen 值运行做出反应的代码。该 if 语句不在某个单独的函数中，因此仅当您加载运行此脚本时才会调用它，而 makeMenuTrue() 甚至一次都没有被调用。

但是 when/if 你又 load/run 它，你 titleScreen = false 无条件执行，所以你不能 titleScreen 存储任何可以被之前更新的信息makeMenuTrue呼唤。

分开吧。使 titleScreen 条件检查成为一个单独的函数，无需重新加载脚本即可调用。或者至少检查 titleScreen 变量是否已经存在，然后在重新加载脚本时将其强制为 false。

Answer 2

您可以简单地使用函数 (showTitleScreen) 而不是变量 (titleScreen)。 if-else 语句中的所有代码我都放在函数体中。

local logo = display.newImage("logo.png", 155, 275)
logo.alpha = 0

local function makeMenuTrue()
    logo:removeSelf()
    print("menu should be TRUE")
    print("WHY DOESN'T IT WORK")
    showTitleScreen()
end

local function fadeOut()
    transition.to(logo, {time = 2000, alpha = 0, onComplete = makeMenuTrue})
end

transition.to(logo, {time = 2000, alpha = 1, onComplete = fadeOut})

local function showTitleScreen()
    print("NOW IT'S TRUE")
    local mainTheme = audio.loadSound ("mainTheme.wav")
    audio.play(mainTheme)

    display.setStatusBar(display.HiddenStatusBar)
    local background1 = display.newImage("Title.png", 155, 275)

    local flare = display.newImage("flare2.png", 40, 30)
    flare.xScale = .5
    flare.yScale = .5
    local flare2 = display.newImage("flare2.png", 400, 70)
    flare2.xScale = .6
    flare2.yScale = .6
    local flare3 = display.newImage("flare2.png", 400, 70)
    flare2.xScale = .4
    flare2.yScale = .4

    local function moveFlare1() 
        transition.to(flare, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare1})
    end
    local function moveFlare2()
        transition.to(flare2, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare2})
    end 
    local function moveFlare3()
        transition.to(flare3, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare3})
    end 

    transition.to(flare, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare1})
    transition.to(flare2, {time=2500, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare2}) 
    transition.to(flare3, {time=2000, x = math.random(-100, 450), y = math.random(-100, 700), onComplete = moveFlare3}) 

--[[local textbox = display.newRect(160, 214, 320, 90)
textbox:setFillColor(.1, .1, .1, .6)
]]

    local textbox = display.newImage("MessageBack2.png", 155, 254, 320, 90)
    textbox.yScale = .7
    local textline = display.newImage("flare2.png", 0, 228)
    textline.xScale = 20
    textline.yScale = .3
    local textOption = 1

    local prompt1 = display.newText ("Start Game", 155, 230, "Goudy Old Style", 20)
    local prompt2 = display.newText ("Continue", 155, 255, "Goudy Old Style", 20)
    local prompt3 = display.newText ("Exit Game", 155, 280, "Goudy Old Style", 20)
    prompt1:setFillColor(0,0,0)

    local function textShrink()
        transition.to(textline, {time = 150, yScale = .3})
    end

    local function moveTextBox()
        if (textOption == 1) then
            textOption = 2 
            transition.to(textline, {time = 200, y = 253, onComplete = textShrink})
            prompt2:setFillColor(0,0,0)
            prompt1:setFillColor(1,1,1)
        else 
            if (textOption == 2) then
                textOption = 3
                transition.to(textline, {time = 200, y = 278, onComplete = textShrink})
                prompt3:setFillColor(0,0,0)
                prompt2:setFillColor(1,1,1)
            else 
                if (textOption == 3) then 
                    textOption = 1
                    transition.to(textline, {time = 200, y = 228, onComplete = textShrink})
                    prompt1:setFillColor(0,0,0)
                    prompt3:setFillColor(1,1,1)
                end
            end
        end
    end

    local function expandText()
        if (textOption == 1 ) then
            print("object 1 has been tapped????")
        else 
            if (textOption == 2) then
                print("object 2 has been tapped????")
            else 
                if (textOption == 3) then
                    print("object 3 has been tapped????")
                end
            end
        end
    end

    transition.to(textline, {time = 150, yScale = .5, 0, onComplete = moveTextBox})
    textbox:addEventListener("tap", expandText)
end

Lua 中的条件分支无缘无故不起作用？

Conditional Branch in Lua isn't working for no clear reason?

lua

sublimetext3

coronasdk