Haxe - Actuate.Tween

Actuate.tween( target : Dynamic , duration : Float , properties : Dynamic , ?overwrite : Bool , ?customActuator : Class<motion.actuators.GenericActuator> )

package;

import flash.display.Sprite;
import flash.events.Event;
import motion.Actuate;
import motion.easing.Quad;

class Main extends Sprite {
    
    public function new () {
        super();
        var size = 5 + Math.random () * 35 + 20;
        var circle = new Sprite ();
        
        circle.graphics.beginFill (Std.int (Math.random () * 0xFFFFFF));    //给精灵填充颜色，颜色随机
        circle.graphics.drawCircle (0, 0, size);                            //画一个圆形，半径随机
        circle.x = 100;                                                        //给精灵赋予初始x位置
        circle.y = 100;                                                        //给精灵赋予初始y位置
        circle.alpha = 0;                                                    //精灵默认为透明

        addChild(circle);                                                    //把圆形精灵加到大精灵中
        Actuate.tween(circle, 10, { alpha : 1});                            //给圆形精灵加动画，持续单位10，从透明变为全部显示
    }
}