ActionScript 2.0 Language Reference - Adobe Help and Support

Also try to avoid setting checkPolicyFile to true if you are using
MovieClipLoader.loadClip() to download a SWF file. This is because SWF-to-SWF
permissions are not controlled by policy files, but rather by Security.allowDomain(), and
checkPolicyFile has no effect when you load a SWF file. Checking for a policy file in this
case is wasteful because it may delay the start of your SWF download and may consume
network bandwidth unnecessarily. (Flash Player cannot tell whether your main download will
be a SWF file or an image, because the policy file download occurs before the main
download.)
Be careful with checkPolicyFile if you are downloading an object from a URL that may use
server-side HTTP redirects. Flash Player always attempts to retrieve policy files that
correspond to the initial URL that you specify in loadClip. If the final object comes from a
different URL because of HTTP redirects, then the initially downloaded policy file(s) might
not be applicable to the object's final URL, which is the URL that matters in security
decisions.
Availability: ActionScript 2.0; Flash Player 9
getProgress (MovieClipLoader.getProgress method)
public getProgress(target:Object) : Object
Returns the number of bytes loaded and the total number of bytes of a file that is being loaded
by using MovieClipLoader.loadClip(); for compressed movies, returns the number of
compressed bytes. The getProgress method lets you explicitly request this information,
instead of (or in addition to) writing a MovieClipLoader.onLoadProgress listener function.
Availability: ActionScript 1.0; Flash Player 7
Parameters
target:Object - A SWF, JPEG, GIF, or PNG file that is loaded by using
MovieClipLoader.loadClip().
Returns
Object - An object that has two integer properties: bytesLoaded and bytesTotal.
Example
The following example demonstrates the use of the getProgress() method. Rather than
using this method, you will usually create a listener object to listen for the onLoadProgress
event. Also note that the first, synchronous call to getProgress() can return the number of
bytes loaded and the total number of bytes of the container and not the values for the
externally requested object.
960 ActionScript classes