Adobe Flex：从位图加载图像时不会触发图像的 Event.COMPLETE

Question

我有一个奇怪的问题。当我设置时，我可以让 Event.COMPLETE 触发

image.source = byteArray;

，但是

当我操作 byteArray - 将其转换为 Bitmap 并使用 image.source 或 image.load 加载它时，位图会正确加载到 Image 组件中；但是 Event.COMPLETE 永远不会触发。这里可能出了什么问题？我也添加了一个完整的事件列表！我的来源如下：

                var bmp:Bitmap = scaleBitmapData(bitmapData,280,220);
                imgPreview.addEventListener(Event.COMPLETE,onPreviewImageCompleted); // never fires
                imgPreview.visible = false;
                imgPreview.load(bmp); // does not work with .source either; image is displayed but Event.Complete never fires!

谢谢 苏拉特

Answer 1

所以这里使用的类是 SWFLoader（Image 扩展了 SWFLoader）。如果您传入 ByteArray 或 url，它会添加适当的侦听器。您所做的就是向其提供一个位图，它是一个显示对象。下面是将位图加载到图像中的重要代码：

 else if (classOrString is DisplayObject)
 {
     contentHolder = child = DisplayObject(classOrString);
     addChild(child);
     contentLoaded();
 }

ByteArray:

else if (byteArray)
{
    loader = new FlexLoader();
    contentHolder = child = loader;
    addChild(child);

    loader.contentLoaderInfo.addEventListener(
        Event.COMPLETE, contentLoaderInfo_completeEventHandler);
    loader.contentLoaderInfo.addEventListener(
        Event.INIT, contentLoaderInfo_initEventHandler);
    loader.contentLoaderInfo.addEventListener(
        IOErrorEvent.IO_ERROR, contentLoaderInfo_ioErrorEventHandler);
    loader.contentLoaderInfo.addEventListener(
        Event.UNLOAD, contentLoaderInfo_unloadEventHandler);

    // if loaderContext null, it will use default, which is AppDomain
    // of child of Loader's context
    loader.loadBytes(byteArray, loaderContext);
}

a url:

else if (url)
{
    // Create an instance of the Flash Player Loader class to do all the work
    loader = new FlexLoader();
    contentHolder = child = loader;

    // addChild needs to be called before load()
    addChild(loader);

    // Forward the events from the Flash Loader to anyone
    // who has registered as an event listener on this Loader.
    loader.contentLoaderInfo.addEventListener(
        Event.COMPLETE, contentLoaderInfo_completeEventHandler);
    loader.contentLoaderInfo.addEventListener(
        HTTPStatusEvent.HTTP_STATUS, contentLoaderInfo_httpStatusEventHandler);
    loader.contentLoaderInfo.addEventListener(
        Event.INIT, contentLoaderInfo_initEventHandler);
    loader.contentLoaderInfo.addEventListener(
        IOErrorEvent.IO_ERROR, contentLoaderInfo_ioErrorEventHandler);
    loader.contentLoaderInfo.addEventListener(
        Event.OPEN, contentLoaderInfo_openEventHandler);
    loader.contentLoaderInfo.addEventListener(
        ProgressEvent.PROGRESS, contentLoaderInfo_progressEventHandler);
    loader.contentLoaderInfo.addEventListener(
        SecurityErrorEvent.SECURITY_ERROR, contentLoaderInfo_securityErrorEventHandler);
    loader.contentLoaderInfo.addEventListener(
        Event.UNLOAD, contentLoaderInfo_unloadEventHandler); 
...[this goes on for awhile]

这样您就明白了要点。不要将其转换为位图，您将获得完整的事件。您还可以将 ADDED_TO_STAGE 添加到位图。