sound类做一个音乐播放器

只实现了一首歌的功能，音量控制，暂停等功能已经实现。

package 
{
	import flash.display.MovieClip;
	import flash.media.Sound;
	import flash.media.SoundChannel;
	import flash.net.URLRequest;
	import flash.events.MouseEvent;
	import fl.events.SliderEvent;
	import flash.media.SoundTransform;
	import flash.events.ProgressEvent;
	import flash.events.Event;
	public class MP3Main extends MovieClip
	{
		private var sound:Sound;
		private var soundchannel:SoundChannel;
		private var position:Number = 0;
		private var soundtransform:SoundTransform;
		private var jiazaitiao:JiaZaiTiao;
		private var jiazaikuang:JiaZaiKuang;
		public function MP3Main()
		{
			sound = new Sound();
			soundchannel = new SoundChannel();
			soundtransform = new SoundTransform();
			jiazaitiao = new JiaZaiTiao();
			jiazaikuang = new JiaZaiKuang();
			jiazaitiao.scaleX = 0;
			jiazaikuang.scaleX = 0;
			jiazaitiao.x = 197;
			jiazaitiao.y = 362;
			xiayishou.label = "上一首";
			shangyishou.label = "下一首";
			btn1.label = "播放";
			btn2.label = "停止";
			slider.value = 10;
			addChild(jiazaitiao);
			addChild(xiayishou);
			addChild(shangyishou);
			sound.load(new URLRequest("Lenka-Trouble Is A Friend.mp3"));
			slider.addEventListener(SliderEvent.CHANGE,onSliderHandler);
			btn1.addEventListener(MouseEvent.CLICK,onClickHandler);
			btn2.addEventListener(MouseEvent.CLICK,onStopHandler);
			sound.addEventListener(ProgressEvent.PROGRESS,onJiaZaiKuangHandler);
			sound.addEventListener(Event.COMPLETE,onJiaZaiTiaoHandler);
			stage.addEventListener(Event.ENTER_FRAME,onEventHandler);
		}

		private function onSliderHandler(e:SliderEvent):void
		{
			soundtransform.volume = (e.target.value)* 0.2;
			soundchannel.soundTransform = soundtransform;
		}
		private function onClickHandler(e:MouseEvent):void
		{
			
			if (btn1.label == "播放")
			{
				soundchannel = sound.play(position);
				btn1.label = "暂停";
			}
			else
			{
				position = soundchannel.position;
				soundchannel.stop();
				btn1.label = "播放";
			}
		}
		private function onStopHandler(e:MouseEvent):void
		{
			soundchannel.stop();
			btn1.label = "播放";
			position = 0;
		}
		private function onJiaZaiKuangHandler(e:ProgressEvent):void
		{
			jiazaikuang.scaleX = e.bytesLoaded / e.bytesTotal;
		}
		private function onJiaZaiTiaoHandler(e:Event):void
		{
			if (btn1.label == "播放")
			{
				soundchannel = sound.play();
			}
			
		  soundchannel.stop();
		}
		private function onEventHandler(e:Event):void
		{
		   jiazaitiao.scaleX = soundchannel.position / sound.length;
		}
	}
}