AS3.0自定义滚动条（滚动内容可以为Sprite或MovieClip等）

本文转自：http://www.cnblogs.com/zhoujunfeng2011/archive/2011/07/15/2106989.html

AS3.0 实现自定义滚动条（滚动内容可以为Sprite 或 MovieClip等），修改属性类型即可！

源码：

Scrollbar.as

package ui
 {
     import flash.display.Sprite;
     import flash.events.MouseEvent;
     import flash.events.Event;
     import ui.ListenManager;
     import flash.geom.Rectangle;
 
     public class Scrollbar extends Sprite
     {
         public var obj:Sprite;//需进行滚动的对象
         public var scrollmask:Sprite;//遮罩对象
         public var scrollheight:Number;//滚动条高度
         public var scrolltextnum:int;//文本显示行数
         public var textspeed:int;//文本滚动速度（行/像素）
         public var Scroll:Sprite;//自定义滚动条对象
         public var bar:Sprite;//滑块
         public var up:Sprite;//向上按钮
         public var down:Sprite;//向下按钮
         public var bg:Sprite;//滑槽
         public var displayobject:*;//接受stage，必须传入
         public var num:int;//计算滑块高度所用
 
         private var bars:Number;//滑块可滑动距离
         private var rect:Rectangle;//滑块可拖动范围
         private var i:int = 0;
         private var n:Number;
         private var listenmanager:ListenManager = new ListenManager();///监听管理器
         构造器函数/
         public function Scrollbar():void
         {
         }
         /初始化函数/
         public function init():void
         {
             if (checkhide())
             {
                 addEventListeners();
             }
             else
             {
                 bar.visible = false;
             }
             setxy();
         }
         ///判断是否显示滚动条等///
         private function checkhide():Boolean
         {
             if (Scroll != null)
             {
                 if (obj.height <= scrollmask.height)
                 {
                     return false;
                 }
                 return true;
             }
             return false;
         }
         ///设置滚动条高度，对象遮罩等
         private function setxy():void
         {
             up.y = 1;
             bg.y = up.height;
             bar.x = 1.2;
             bar.y = bg.y;
             if (bar.height >= 10)
             {
                 n = (obj.height - scrollmask.height)/(num+20);
                 bar.height = scrollmask.height - (obj.height - scrollmask.height)/n;
             }
             bg.height = scrollheight;
             down.y = bg.y + bg.height;
             bars = bg.height - bar.height;
             obj.mask = scrollmask;
             rect = new Rectangle(bar.x,bg.y,0,bg.height - bar.height);
         }
         ///当被滚动对象更新时，而需要改变滚动条状态，调用此方法///
         public function update(num:int):void
         {
             if (checkhide())
             {
                 i++;
                 if (bar.height >= 10)
                 {
                     n = (obj.height - scrollmask.height)/(num+20);
                     bar.height = scrollmask.height - (obj.height - scrollmask.height)/n;
                 }
                 bar.y = bg.y + bg.height - bar.height;
                 bar.y +=  bars * textspeed /(obj.height - scrollmask.height);
                 obj.y = scrollmask.y - obj.height + scrollmask.height;
                 objrun(textspeed);
                 updatebar();
                 bars = bg.height - bar.height;
                 rect = new Rectangle(bar.x,bg.y,0,bg.height - bar.height);
                 if (i == 1)
                 {
                     bar.visible = true;
                     addEventListeners();
                 }
             }
         }
         ///为滚动条添加监听事件
         private function addEventListeners():void
         {
             listenmanager.fcn_add(bar,MouseEvent.MOUSE_DOWN,barclick);
             listenmanager.fcn_add(bar,MouseEvent.MOUSE_UP,barup);
             listenmanager.fcn_add(displayobject,MouseEvent.MOUSE_UP,barup);
             listenmanager.fcn_add(up,MouseEvent.MOUSE_DOWN,upclick);
             listenmanager.fcn_add(down,MouseEvent.MOUSE_DOWN,downclick);
             listenmanager.fcn_add(Scroll,MouseEvent.MOUSE_WHEEL,mousewheel);
             listenmanager.fcn_add(obj,MouseEvent.MOUSE_WHEEL,mousewheel);
         }
         ///鼠标点击滑块方法///;
         private function barclick(evt:MouseEvent):void
         {
             bar.startDrag(false,rect);
             listenmanager.fcn_add(bar,Event.ENTER_FRAME,bar_enter_frame);
         }
         ///鼠标点击滑块释放方法///;
         private function barup(evt:MouseEvent):void
         {
             bar.stopDrag();
             delevent();
         }
         ///鼠标点击向上按钮方法///
         private function upclick(evt:MouseEvent):void
         {
             if (checkbar())
             {
                 bar.y -= bars * textspeed /(obj.height-scrollmask.height);//滑块移动的距离=滚动对象滚动的像素*滑块可移动的总距离/(被滚动对象的高度-遮罩的高度（即显示范围的高度))
                 objrun(0-textspeed);
                 //调用方法移动对象;
                 updatebar();//校正滑块位置
             }
         }
         ///鼠标点击向下按钮方法///
         private function downclick(evt:MouseEvent):void
         {
             if (checkbar())
             {
                 bar.y +=  bars * textspeed /(obj.height - scrollmask.height);
                 objrun(textspeed);
                 updatebar();
             }
         }
         ///鼠标滑轮事件///
         private function mousewheel(evt:MouseEvent):void
         {
             if (evt.delta > 0)
             {
                 if (checkbar())
                 {
                     bar.y -=  bars * textspeed /(obj.height - scrollmask.height);
                     objrun(-textspeed);
                     updatebar();
                 }
             }
             else
             {
                 if (checkbar())
                 {
                     bar.y +=  bars * textspeed /(obj.height - scrollmask.height);
                     objrun(textspeed);
                     updatebar();
                 }
             }
         }
         private function bar_enter_frame(evt:Event):void
         {
             obj.y = scrollmask.y - (bar.y - bg.y)*(obj.height - scrollmask.height)/bars;
             if (obj.y > scrollmask.y)
             {
                 obj.y = scrollmask.y;
             }
             else if (obj.y < (scrollmask.y - obj.height + scrollmask.height))
             {
                 obj.y = scrollmask.y - obj.height + scrollmask.height;
             }
         }
         private function objrun(i:Number):void
         {
             obj.y -=  i;
             if (obj.y > scrollmask.y)
             {
                 obj.y = scrollmask.y;
             }
             else if (obj.y < (scrollmask.y - obj.height + scrollmask.height))
             {
                 obj.y = scrollmask.y - obj.height + scrollmask.height;
             }
         }
         private function checkbar():Boolean
         {
             if (bar.y >= bg.y && bar.y <= (bars + bg.y))
             {
                 return true;
             }
             return false;
         }
         ///删除卸载事件侦听///
         private function updatebar():void
         {
             if (bar.y < bg.y)
             {
                 bar.y = bg.y;
             }
             else if (bar.y >(bg.y + bg.height - bar.height))
             {
                 bar.y = bg.y + bg.height - bar.height;
             }
         }
         private function delevent():void
         {
             listenmanager.fcn_del(bar,Event.ENTER_FRAME,bar_enter_frame);
         }
     }
 }

ListenManager.as

package ui
 {
     import flash.display.Sprite;
     public class ListenManager extends Sprite
     {
         public function ListenManager()
         {
 
         }
         public function fcn_add(obj:*,_type:String,fcn:Function):void
         {
             obj.addEventListener(_type,fcn);
         }
         public function fcn_del(obj:*,_type:String,fcn:Function):void
         {
             obj.removeEventListener(_type,fcn);
         }
     }
 }

loader.as

package ui
 {
     import flash.display.Loader;
     public class loader extends Loader
     {
         private var Name:String;
         public function loader():void
         {
         }
         public function get Names():String
         {
             return Name;
         }
         public function set Names(myname:String):void
         {
             Name = myname;
         }
     }
 }

simple.as

package ui
 {
     import flash.display.Sprite;
     import flash.display.SimpleButton;
     import flash.text.TextField;
     import flash.text.TextFormat;
     import flash.text.TextFieldAutoSize;
 
     public class simple extends Sprite
     {
         private var btnw:Number;
         private var btnh:Number;
         private var downcolor:uint;
         private var upcolor:uint;
         private var overcolor:uint;
         private var lineStly:Boolean;
         public function simple():void
         {
 
         }
         public function getsimplebtn(str:String,btnw:Number = 50,btnh:Number = 30,downcolor:uint = 0x990066,upcolor:uint = 0xffffff,overcolor:uint = 0x666666,lineStly:Boolean = false):SimpleButton
         {
             this.name = str;
             this.btnw = btnw;
             this.btnh = btnh;
             this.downcolor = downcolor;
             this.upcolor = upcolor;
             this.overcolor = overcolor;
             this.lineStly = lineStly;
             var btn:SimpleButton = new SimpleButton();
             btn.downState = downbtn();
             btn.upState = upbtn();
             btn.overState = overbtn();
             btn.hitTestState = hitbtn();
             return btn;
         }
         private function hitbtn():Sprite
         {
             var sprite:Sprite = new Sprite();
             sprite.graphics.beginFill(upcolor);
             sprite.graphics.drawRect(0,0,btnw,btnh);
             sprite.graphics.endFill();
             return sprite;
         }
         private function downbtn():Sprite
         {
             var txt:TextField = txtstr(this.name);
             var sprite:Sprite = DrawSprite(1);
             sprite.addChild(txt);
             return sprite;
         }
         private function upbtn():Sprite
         {
             var txt:TextField = txtstr(this.name);
             var sprite:Sprite = DrawSprite(0);
             sprite.addChild(txt);
             return sprite;
         }
         private function overbtn():Sprite
         {
             var txt:TextField = txtstr(this.name);
             var sprite:Sprite = DrawSprite(2);
             sprite.addChild(txt);
             return sprite;
         }
         private function txtstr(str:String):TextField
         {
             var txt:TextField = new TextField();
             var format:TextFormat = new TextFormat();
             format.font = "Verdana";
             format.size = 12;
             txt.autoSize = TextFieldAutoSize.LEFT;
             txt.text = str;
             txt.setTextFormat(format);
             return txt;
         }
         private function DrawSprite(n:int):Sprite
         {
             var sprite:Sprite = new Sprite();
             if (n == 0)
             {
                 sprite.graphics.beginFill(upcolor);
             }
             else if (n == 1)
             {
                 sprite.graphics.beginFill(downcolor);
             }
             else if (n == 2)
             {
                 sprite.graphics.beginFill(overcolor);
             }
             if(lineStly)
             {
                 sprite.graphics.lineStyle(1,0x660099);
             }
             sprite.graphics.drawRect(0,0,btnw,btnh);
             sprite.graphics.endFill();
             return sprite;
         }
     }
 }

文档类:Main.as

package 
 {
     import flash.display.Sprite;
     import ui.simple;
     import ui.Scrollbar;
     import flash.display.SimpleButton;
     import flash.events.MouseEvent;
     import flash.display.Shape;
     import flash.net.URLLoader;
     import flash.events.Event;
     import flash.net.URLRequest;
     import ui.loader;
     import flash.display.Bitmap;
     import flash.text.TextField;
 
     public class Main extends Sprite
     {
         private var backbox:Sprite = new Sprite();
         private var sprite:Sprite = new Sprite();
         private var scrollcont:Sprite = new Sprite();
         private var i:int = 0;
         private var j:int = -1;
         private var num:int;
         private var bg:Sprite = new Sprite();
         private var bar:Sprite = new Sprite();
         private var up:Sprite = new Sprite();
         private var down:Sprite = new Sprite();
         private var listscroll:Scrollbar = new Scrollbar();
         public function Main():void
         {
             init();
         }
         private function init():void
         {
             var urlloader:URLLoader = new URLLoader();
             urlloader.addEventListener(Event.COMPLETE,com);
             urlloader.load(new URLRequest("http://files.cnblogs.com/zhoujunfeng2011/Pictures/data.xml"));
         }
         private function com(evt:Event):void
         {
             var myxml:XML = new XML(evt.target.data);
             num = myxml.child("pic").length();
             for (var i:int =0; i<num; i++)
             {
                 var myloader:loader = new loader();
                 myloader.contentLoaderInfo.addEventListener(Event.COMPLETE,piccom);
                 myloader.load(new URLRequest(myxml.child("pic")[i].@url));
                 myloader.Names = myxml.child("pic")[i]. @ name;
             }
         }
         private function piccom(evt:Event):void
         {
             j++;
             var myloader:loader = loader(evt.target.loader);
             var bitmap:Bitmap = Bitmap(myloader.content);
             var sprite:Sprite = new Sprite();
             sprite.addChild(bitmap);
             switch (myloader.Names)
             {
                 case "滑块" :
                     bar = sprite;
                     break;
                 case "滑槽" :
                     bg = sprite;
                     break;
                 case "向上" :
                     up = sprite;
                     break;
                 case "向下" :
                     down = sprite;
                     break;
             }
             if (j == num-1)
             {
                 uiinit();
             }
         }
         private function uiinit():void
         {
             var btn:simple = new simple();
             var spmask:Sprite = new Sprite();
             var Test_btn:SimpleButton;
             backbox.graphics.beginFill(0xffffff);
             backbox.graphics.lineStyle(1,0x660099);
             backbox.graphics.drawRect(0,0,200,241);
             backbox.graphics.endFill();
             backbox.y = 10;
             addChild(backbox);
             scrollcont.x = backbox.width - 14;
             scrollcont.y = backbox.y;
             addChild(scrollcont);
             down.y = scrollcont.y;
             scrollcont.addChild(down);
             scrollcont.addChild(bg);
             scrollcont.addChild(up);
             scrollcont.addChild(bar);
             spmask.graphics.beginFill(0x000000);
             spmask.graphics.drawRect(0,0,backbox.width,backbox.height);
             spmask.graphics.endFill();
             backbox.addChild(sprite);
             backbox.addChild(spmask);
             Test_btn = btn.getsimplebtn("点击添加",60,30,0xff00cc,0xcc00cc,0x9900cc);
             Test_btn.x = 65;
             Test_btn.y = backbox.height + 15;
             this.addChild(Test_btn);
             for (i; i< 120; i++)
             {
                 var sbtn:simple = new simple();
                 var sp:SimpleButton;
                 var str:String = i + 1 + " this is Testing!";
                 sp = sbtn.getsimplebtn(str,185,20,0x990099,0x66ffff,0x99ffff,true);
                 sp.x = 1;
                 sp.y = i * 20;
                 sprite.addChild(sp);
             }
             listscroll.displayobject = this.stage;
             listscroll.obj = sprite;
             listscroll.scrollmask = spmask;
             listscroll.textspeed = 20;
             listscroll.Scroll = scrollcont;
             listscroll.scrollheight = 212;
             listscroll.up = up;
             listscroll.down = down;
             listscroll.bg = bg;
             listscroll.bar = bar;
             listscroll.num = i;
             listscroll.init();
             Test_btn.addEventListener(MouseEvent.CLICK,Testbtn_click);
         }
         private function Testbtn_click(evt:MouseEvent):void
         {
             var sbtn:simple = new simple();
             var sp:SimpleButton;
             var str:String = i + 1 + " this is Testing!";
             sp = sbtn.getsimplebtn(str,185,20,0x990099,0x66ffff,0x99ffff,true);
             sp.x = 1;
             sp.y = i * 20;
             sprite.addChild(sp);
             listscroll.update(i);
             i++;
         }
     }
 }

为图方便所以使用了SimpleButton类型作为列表中的内容， ，有些算法都是从网上收集起来的，不过稍改了下 ，希望会对你有帮助，代码有点乱，看了后希望点评下，谢谢！最后加上XML内容：

<?xml version="1.0" encoding="utf-8"?>
 <data>
     <pic name="滑槽" url="http://files.cnblogs.com/zhoujunfeng2011/Pictures/bg.png"/>
     <pic name="向上" url="http://files.cnblogs.com/zhoujunfeng2011/Pictures/up.png"/>
     <pic name="向下" url="http://files.cnblogs.com/zhoujunfeng2011/Pictures/down.png"/>
     <pic name="滑块" url="http://files.cnblogs.com/zhoujunfeng2011/Pictures/bar.png"/>
 </data>