[css-ui-4] the appearance property

Another feature I am tackling in CSS UI level 4 is the appearance
property.

The design I am proposing here differs from the original approach,
last seen in an official spec in the 2004 CSS3-UI WD[1], and which
inspired the (poorly interoperable) experimental implementations
in Gecko[2] and Webkit[3].

This property is most commonly used in the wild with value ''none''
to disable native styling of form controls. So my design focused
on making ''none'' work, and uses ''auto'' as a default value,
although I do allow the possibility of a few other values and have
included ''button'' for now.

This approach is summarized in the following note from my draft:

> This specification intentionally refrains from making the appearance
> of all possible form controls and sub-controls available as values,
> as had previously been attempted by earlier proposals for this
> property and by several UA vendors in experimental implementations.
> Experience as shown that such a list would be very long and not
> practical to maintain, and UAs would need to add non-standard
> values to account for the behavior of non-standard pseudo-elements
> sometimes used to implement form controls. Moreover, many values of
> such an enumeration only make sense on a single element or
> pseudo-element, and are never used outside of the UA stylesheet.
> Instead, this specification will only provide auto, none, and values
> which are useful in an author or user stylesheet and for which
> interoperability can be achieved. UAs cannot therefore use the
> appearance property in the UA stylesheet to give each control is
> native look and feel, and must use appearance:auto instead.


For all the gory details, go here:

http://dev.w3.org/csswg/css-ui-4/#appearance-switching

Feedback appreciated.

 - Florian

[1]http://www.w3.org/TR/2004/CR-css3-ui-20040511/
[2]https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-appearance
[3]https://developer.apple.com/library/safari/documentation/AppleApplications/Reference/SafariCSSRef/Articles/StandardCSSProperties.html#//apple_ref/doc/uid/TP30001266-_webkit_appearance

Received on Thursday, 2 April 2015 15:22:59 UTC