Flash AS制作一个铅笔画图程序

this.attachMovie("cursor_id", "cursor_mc", this.getNextHighestDepth(), 
{_x:_xmouse, _y:_ymouse});
Mouse.hide();
var mouseListener:Object = new Object();
mouseListener.onMouseMove = function() {
pencil._x = _xmouse;
pencil._y = _ymouse;
updateAfterEvent();
};//建立一个铅笔图标
Mouse.addListener(mouseListener);//和铅笔图片联系在一起
this.createEmptyMovieClip("drawing_mc", this.getNextHighestDepth());
var mouseListener:Object = new Object();
mouseListener.onMouseDown = function() {
 this.drawing = true;
drawing_mc.moveTo(_xmouse, _ymouse);
 drawing_mc.lineStyle(3, 0x99CC00, 100);
};
mouseListener.onMouseUp = function() {
this.drawing = false;
};
mouseListener.onMouseMove = function() {
 if (this.drawing) {
drawing_mc.lineTo(_xmouse, _ymouse);
}
updateAfterEvent();
};
Mouse.addListener(mouseListener);
var keyListener:Object = new Object();
keyListener.onKeyDown = function() {
if (Key.isDown(Key.DELETEKEY) || Key.isDown(Key.BACKSPACE)) {
drawing_mc.clear();
}
};
Key.addListener(keyListener);