Actionscript 3 Actionscript错误#1009无法访问空对象引用的属性或方法

我只是一个初学者，我真的很感谢你的帮助。 这是我的代码：

import flash.events.MouseEvent;
import flash.display.MovieClip;

var currentButton:MovieClip
button1.addEventListener(MouseEvent.CLICK, mouseClick);
button2.addEventListener(MouseEvent.CLICK, mouseClick);
button3.addEventListener(MouseEvent.CLICK, mouseClick);
button4.addEventListener(MouseEvent.CLICK, mouseClick);
function mouseClick(event:MouseEvent):void {
    currentButton.alpha = 1;
    currentButton.mouseEnabled = true;
    currentButton = event.target as MovieClip;
    trace("CLICK");
    currentButton.alpha = 0.7;
    currentButton.mouseEnabled = false;
}

但是当我点击一个按钮时，我得到了这个错误：

TypeError:错误#1009:无法访问空对象引用的属性或方法。 在未命名的佛罗里达州：MainTimeline/mouseClick（）

---

您的代码似乎与

currentButton

对象存在一些问题

我想在鼠标单击函数的开头添加以下行可以解决您的问题：

function mouseClick(event:MouseEvent):void {
    var currentButton:MovieClip = event.currentTarget; // Giving proper type to an object is better practise, but since your button objects appear unknown, I have assumed them as MovieClip
    currentButton.alpha = 1;
...