如何：将整个函数插入组（场景组）

Question

我知道如何将单个变量放入组中，但如果我需要组中的一个函数（这样当我去制作场景时，我可以将整个函数插入到 sceneGroup 中，而不是输入每个变量单独）我将如何插入？

代码：

function scene:create(event) 
    local sceneGroup = self.view
end

function scene:show(event)
    local sceneGroup = self.view
    local phase = event.phase

    if (phase == "will") then
     sceneGroup:insert(HomePage()) --- this is what I have tried

    elseif (phase == "did") then

    end
end


scene:addEventListener("create", scene)
scene:addEventListener("show", scene)
scene:addEventListener("hide", scene)
scene:addEventListener("destroy", scene)

return scene

scene1.lua:140: 错误：需要表。如果这是一个函数调用，您可能使用了 '.'而不是'：'

这是我收到的错误消息。

我也试过

sceneGroup:insert(HomeGroup) --- this is without the () at the end, at it still fails to work.

如果您有任何想法或知道如何执行此操作，请告诉我。

Answer 1

您不能将功能添加到显示组。由于 sceneGroup 是一个表（就像 lua 中的大部分内容一样），您可以像这样声明 HomePage：

sceneGroup.HomePage = function(params)
    -- code for HomePage
end

如果你想通过composer.setVariable和composer.getVariable给composer添加一个函数，你有这个选项。

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

-- locals
local testFunc = function(hello)
    print(hello)
end

-- "scene:create()"
function scene:create( event )
    local sceneGroup = self.view

    -- create a variable called "myFuntion" with the value of a reference to testFunc
    composer.setVariable( "myFunction", testFunc )
end


-- "scene:show()"
function scene:show( event )

    local sceneGroup = self.view
    local phase = event.phase

    if ( phase == "did" ) then
        -- Called when the scene is now on screen.
        composer.getVariable( "myFunction" )("Testing!")
    end
end

-- Listener setup
scene:addEventListener( "create", scene )
scene:addEventListener( "show", scene )

return scene

一旦场景在屏幕上完成动画，这将打印“Testing”。

但是，我看不出这样做的目的。如果您想为您的作曲家场景添加一个功能，我建议您使用这种方法。

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

-- local forward references for FUNCTIONS should go here
local myFunction

-- "scene:create()"
function scene:create( event )
    local sceneGroup = self.view

    -- init functions here
    myFunction = function(param)
        print("myFunction says "..param)
    end
end


-- "scene:show()"
function scene:show( event )

    local sceneGroup = self.view
    local phase = event.phase

    if ( phase == "did" ) then
        -- Called when the scene is now on screen.
        myFunction("hello")
    end
end

-- "scene:destroy()"
function scene:destroy( event )

    local sceneGroup = self.view

    -- remove your scene's functions here
    myFunction = nil
end

-- Listener setup
scene:addEventListener( "create", scene )
scene:addEventListener( "show", scene )
scene:addEventListener( "destroy", scene )

return scene

如您所见，myFunction 可以在整个场景中调用，没有任何问题。一旦场景在屏幕上完成动画，此示例将打印“myFunction say hello”。

希望这会有所帮助，

乔。