在Love2D中超类调用超类方法

Question

如何在Love2D中的子类中调用超类方法？

Sprite = {} 
function Sprite:new(x, y, image) 
    local self = {} 
    self.x = x 
    self.y = y 
    self.image = image 

    function self:draw() 
     love.graphics.draw(self.image, self.x, self.y) 
    end 
    return self 
end 

ExplorerWindow = {} 
function ExplorerWindow:new(x, y, image) 
    local self = Sprite:new(x, y, image) 

    function self:draw() 
     -- Here I want to call draw in Sprite 
    end 
    return self 
end 

function love.load() 
    explorerWindow = ExplorerWindow:new(200, 200, love.graphics.newImage("res/window.png")) 
end 

function love.draw() 
    explorerWindow:draw() 
end 

Answer 1

将较旧的函数存储在临时变量中。

function ExplorerWindow:new(x, y, image) 
    local self = Sprite:new(x, y, image) 
    local oldDraw = self.draw 

    function self:draw() 
     oldDraw(self) 
    end 
    return self 
end 

另外，请相应地使用setmetatable。