I'm looking into fixing bug 443978 (allow general mutation of @font-face rules from JavaScript). This involves being able to call back into the CSS parser, and to do that you have to have a whole bunch of document state. All of that state is reachable from the stylesheet object - but it takes 40 lines of code to dig it all out. There is a helper method nsDOMCSSDeclaration::GetCSSParsingEnvironment which does just that, but it's only available as a concrete method if you are a DOMCSSDeclarationImpl or a nsDOMCSSAttributeDeclaration - approximately, if you are a regular style declaration (specified in CSS or poked in from JS, respectively, I think). There is also similar logic embedded in nsCSSStyleSheet methods but not where one can get at it.
I would like to generalize this logic so it is available to all non-style rules - if you look through nsCSSRules.cpp you will see that many of them do not implement SetCssText, and this looks like the major obstacle to me (we would also need to expose more CSSParserImpl methods, but that's easy). The most straightforward way to do that seems to be to add GetCSSParsingEnvironment methods to nsCSSStyleSheet and nsCSSRule - these could replace some of the existing code, at least for DOMCSSDeclarationImpl. Does anyone have a better idea? I'm also not sure how to notify the world that the rule has changed. There are nsCSSStyleSheet methods for that, but they're internal and appear to be valid only for plain old style rules (I could be wrong). Any help there would be appreciated. Thanks, zw _______________________________________________ dev-tech-layout mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-layout
