As you have seen, the
section may contain either inline content—including HTML, CSS, and
file, which is the URL value of the
href attribute, needs to be a file of type
HTML, XHTML, PHP, or any other server-side language. The proxy cannot
be, for instance, a link to a .swf
Flash file, an image, or a .mov
QuickTime movie. To embed these items, you must wrap them in an HTML
document and serve them via that file.
“Is it better to inline your content or have a proxy?” is usually
one of the first questions that comes up when developers start building
their applications. As far as the accessibility of container-specific
features, there are really no differences between the two methods. When
a gadget is rendered, all
sections are concatenated together in a similar fashion. Choosing one
method over another really comes down to maintainability, number of
server requests, and load time.
Most containers internally cache the gadget XML files that are uploaded to their systems so they can serve up gadgets quickly. Once you make edits to a gadget XML file, these containers will require you to reupload or update their cache by syncing the XML file. This can be a tedious task depending on how the container handles caching, and if you inline your content inside the gadget XML file, you will have to do it each time you wish to view edits.
On the other hand, if you proxy your content using ...