» Loader

这是渐进式加载图片的升级版demo，如果你看不到这个flash，请到文章页面查看！ 渐进式加载类渐进加载jpg图片。 这个版本跟上个版本不同，主要修复加载时会闪烁的问题。 ProgressivePlusLoader package { import flash.display.DisplayObject; import flash.display.LoaderInfo; import flash.display.Sprite; import flash.errors.IOError; import flash.events.Event; import flash.events.IOErrorEvent; import flash.events.ProgressEvent; import flash.events.SecurityErrorEvent; import flash.system.LoaderContext; import flash.display.Loader; import flash.net.URLRequest; import flash.net.URLStream; import flash.utils.ByteArray; /** * 加载完成 */ /** * 加载进度 */ /** * IOError时触发 */ /** * 渐进式加载类 * * @author lite3 */ public class ProgressivePlusLoader extends Sprite { private var loader0:Loader; private var loader1:Loader; private var showingLoader:Loader; // 当前显示的loader private var _bytesLoaded:uint 0; // 已加载的字节数 private var _bytesToal:uint 0; // 总字节数 private var loading:Boolean false; // 是否有Loader正在加载 private var dataChange:Boolean false; // buffer的数据是否改变 private var streamComplete:Boolean false; // 文件是否加载完成 private var context:LoaderContext; // private var buffer:ByteArray; // 数据缓存 private var stream:URLStream; // 流 public function ProgressivePlusLoader() { loader0 new Loader(); loader1 new Loader(); super.addChild(loader0); super.addChild(loader1); } /** * 卸载数据 */ public function unload():void { close(); loader0.unload(); loader1.unload(); } /** * 关闭流,并清理所有侦听器 */ public function close():void { // 清除流相关 if (stream) { if (stream.connected) stream.close(); streamRemoveEvent(stream); } // 清除conentLoaderInfo相关的事件 loaderInfoRemoveEvent(loader0.contentLoaderInfo); loaderInfoRemoveEvent(loader1.contentLoaderInfo); streamComplete false; dataChange false; buffer null; } /** * 加载字节数据 * @param bytes * @param context */ public function loadBytes(bytes:ByteArray, context:LoaderContext null):void { close(); unload(); streamComplete true; dataChange false; loading false; this.context context; var loader:Loader getHideLoader(); loader.loadBytes(bytes, context); loaderInfoRemoveEvent(loader.contentLoaderInfo); } /** * 加载一个url文件,并渐进显示(如果是渐进格式) * @param request * @param context */ public function load(request:URLRequest, context:LoaderContext null):void { if (!stream) stream new URLStream(); if (stream.connected) stream.close(); this.context context; streamComplete false; dataChange false; loading false; unload(); buffer new ByteArray(); loaderInfoAddEvent(loader0.contentLoaderInfo); loaderInfoAddEvent(loader1.contentLoaderInfo); streamAddEvent(stream); stream.load(request); } /** 已加载的字节数 */ public function get bytesLoaded():uint { return _bytesLoaded; } /** 总字节数 */ public function get bytesToal():uint { return _bytesToal; } override public function addChild(child:DisplayObject):DisplayObject { throw new Error("ProgressiveLoader类不实现此方法!"); return null; } override public function addChildAt(child:DisplayObject, index:int):DisplayObject { throw new Error("ProgressiveLoader类不实现此方法!"); return null; } override public function removeChild(child:DisplayObject):DisplayObject { throw new Error("ProgressiveLoader类不实现此方法!"); return null; } override public function removeChildAt(index:int):DisplayObject { throw new Error("ProgressiveLoader类不实现此方法!"); return null; } override public function swapChildren(child1:DisplayObject, child2:DisplayObject):void { throw new Error("ProgressiveLoader类不实现此方法!"); } override public function swapChildrenAt(index1:int, index2:int):void { throw new Error("ProgressiveLoader类不实现此方法!"); } // 将缓存中的数据显示为图像 private function showData():void { if (loading || !dataChange) return; if (buffer.length > 0) { dataChange false; getHideLoader().loadBytes(buffer, context); loading true; } } private function showLoader(loader:Loader):void { showingLoader loader; loader0.visible loader loader0; loader1.visible loader loader1; } private function getHideLoader():Loader { return showingLoader loader0 ? loader1 : loader0; } // 显示完成 private function loaderCompleteHandler(e:Event):void { showLoader(e.target.loader); loading false; if (streamComplete && !dataChange) { close(); dispatchEvent(new Event(Event.COMPLETE, false, false)); }else { showData(); } } // 数据加载完成 private function streamCompleteHandler(e:Event):void { streamRemoveEvent(stream); if (stream.bytesAvailable > 0) { stream.readBytes(buffer, buffer.length, stream.bytesAvailable); dataChange true; } _bytesLoaded _bytesToal; streamComplete true; showData(); } // 数据加载中,保存数据加载的值 private function streamProgressHandler(e:ProgressEvent):void { _bytesLoaded e.bytesLoaded; _bytesToal e.bytesTotal; if (stream.bytesAvailable > 0) { stream.readBytes(buffer, buffer.length, stream.bytesAvailable); dataChange true; } showData(); dispatchEvent(new ProgressEvent(ProgressEvent.PROGRESS, false, false, _bytesLoaded, _bytesToal)); } // 流错误 private function streamErrorHandler(e:IOErrorEvent):void { close(); dispatchEvent(new IOErrorEvent(IOErrorEvent.IO_ERROR, false, false, e.text)); } private function streamAddEvent(stream:URLStream):void { stream.addEventListener(Event.COMPLETE, streamCompleteHandler); stream.addEventListener(ProgressEvent.PROGRESS, streamProgressHandler); stream.addEventListener(IOErrorEvent.IO_ERROR, streamErrorHandler); } private function streamRemoveEvent(stream:URLStream):void { stream.removeEventListener(Event.COMPLETE, streamCompleteHandler); stream.removeEventListener(ProgressEvent.PROGRESS, streamProgressHandler); stream.removeEventListener(IOErrorEvent.IO_ERROR, streamErrorHandler); } private function loaderInfoAddEvent(loaderInfo:LoaderInfo):void { loaderInfo.addEventListener(Event.COMPLETE, loaderCompleteHandler); } private function loaderInfoRemoveEvent(loaderInfo:LoaderInfo):void { loaderInfo.removeEventListener(Event.COMPLETE, loaderCompleteHandler); } } } 示例源码

LiteFeel

ProgressivePlusLoader 渐进式加载图像更新

Loader 加强版 LoaderPlus

LiteFeel

ProgressivePlusLoader 渐进式加载图像 更新

Loader 加强版 LoaderPlus

ProgressivePlusLoader 渐进式加载图像更新