当按下按钮时激活得分的功能无法正常工作，Corona SDK。

我希望在按下按钮时才增加分数。但是我尝试运行我的代码时，分数没有改变...有什么想法吗？ 先提前感谢！

这是我的代码：

score = 0

local scoreNumber = display.newText(score, 200, 30, nil, 20)
scoreNumber.xScale = 1.2
scoreNumber.yScale = 1.2

local scoreText = display.newText("score:", 150, 30, nil, 20)
scoreText.xScale = 1.2
scoreText.yScale = 1.2

local buttonPressed = false

local myButton = display.newRect(50,50,100,100)

local function scoretimer(event)
if buttonPressed then

    score = score + 1
    scoreNumber.text = score
    end
end

local function buttonPressed(event)
     if event.phase == "began" then
          buttonPressed = true

     elseif event.phase == "ended" then
          buttonPressed = false
     end
     return true
 end

 myButton:addEventListener("touch", buttonPressed)

 Runtime:addEventListener("enterFrame", scoretimer)