71262 - Add support for <stylesheet src=""> to XBL

Status: RESOLVED FIXED

(Core :: XBL, defect)

Description

[David Hyatt]

Instead of improperly using the PI for loading stylesheets, XBL should have its
own stylesheet loading directive.

Comment 1

[David Hyatt]

Attachment: Patch to XBL code (also fixed a bug in the CSS loader).

Comment 2

[David Hyatt]

*** Bug 58758 has been marked as a duplicate of this bug. ***

Comment 3

[Mike Shaver (:shaver emeritus)]

sr=shaver.

Comment 4

[Peter "jag" Annema]

+    nsCOMPtr<nsIContent> content(do_QueryInterface(supp));
+    nsCOMPtr<nsIDocument> doc;
+    content->GetDocument(*getter_AddRefs(doc));
+    
+    PRBool ready = PR_FALSE;
+    xblService->BindingReady(content, bindingURI, &ready);
+
+    if (ready) {

You could move the |doc| declaration and getter inside the |if (ready)|

r=jag

Comment 5

[Heikki Toivonen (remove -bugzilla when emailing directly)]

Is this absolutely necessary? Can't we reuse the standard ways of loading
stylesheets (PI in a document prolog or XHTML link element)?

Comment 6

[Hixie (not reading bugmail)]

heikki: XBL allows you to scope stylesheets so that they don't affect other 
bindings. For example, if your <button> binding uses several <div>s in its 
generated content, then the stylesheet for the binding could say
   div { border: solid }
...without affecting any other <div> elements in the document. This is the basis
of skinning widgets. That's why we want this.

Now as to why we want to do it this way: Per the specs, the XML PI would load 
the stylesheet for the binding document if you viewed the binding document. If
you just link in to the binding document, it shouldn't do anything particularly
clever with it -- the XML PI doesn't apply to the bound element, but to the
binding document. Also, using an element as hyatt proposes here means you can
have binding stylesheets on a per-binding basis -- the XML PI applies to an 
entire document.

The reason we don't use <html:link> is because XBL has nothing to do with HTML
and so there is no reason to use it. (This is just like SVG -- they don't use
the HTML <style> element, they have their own.)

Comment 7

[Heikki Toivonen (remove -bugzilla when emailing directly)]

Ok, I buy it (actually after reading the dupe I realized this was probably the
case). Does the stylesheet element have type attribute, a la the stylesheet PI?
Theoretically at least you should probably be able to use any style language
you'd want...

Comment 8

[David Hyatt]

It supports type and media.  It does not support title, since alternate
stylesheets in this context are non-sensical.

Comment 9

[David Hyatt]

Fixed.