ISSUE-2238: Add @allowReorder to <switch>


Add @allowReorder to <switch>

Raised by:
Doug Schepers
Opened on:
Per SMIL 3.0:

Authors should order the alternatives from the most desirable to the least desirable. Furthermore, authors may wish to place a relatively fail-safe alternative as the last item in the switch so that at least one item within the switch is chosen (unless this is explicitly not desired). If all alternatives are equivalent an author should signal this through the allowReorder attribute on the switch, this gives the user agent the freedom to pick the best match (as opposed to the first match).
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The allowReorder Attribute

The allowReorder attribute signals whether a user agent may reorder the direct descendents of the switch element, based on user preferences, if it thinks this could lead to a better user experience.

The possible values are 'no', the default, disallowing reordering and 'yes', allowing reordering.

This section is informative.

User agents are free to ignore the allowReorder attribute, but if they implement prioritized language ranges as defined in BCP47 [BCP47] they are expected to use that prioritization to reorder children with systemLanguage attributes. The effect should be that the users are presented with the alternative that best matches their language preferences. Any final child without systemLanguage attribute should retain its place as the default item to present.

Authors should add the allowReorder attribute if all items in the switch are equivalent.
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Note that this language is a bit unclear and doesn't use normative language, so though we should reference it, we should also make it clearer. Also, they seem to make it optional, which SVG should not.

We should also look into tests the SMIL WG may have produced for this.

Related Actions Items:
Related emails:
  1. Minutes F2F Pyrmont, Sydney day 1 (04/01/2013) (from on 2013-02-04)
  2. Fwd: Minutes, SVG f2f Mountain View, Thurs 27 Oct 2011 (from on 2011-10-28)
  3. minutes, SVG Working Group Mountain View F2F, day 2 (from on 2011-10-28)
  4. Minutes, SVG f2f Mountain View, Thurs 27 Oct 2011 (from on 2011-10-28)
  5. Minutes, March 19 2009 telcon (from on 2009-03-20)
  6. ISSUE-2238 (switch-allowReorder): Add @allowReorder to <switch> [SVG Core 2.0] (from on 2009-03-19)

Related notes:

Doug Schepers, 19 Mar 2009, 04:23:18

ISSUE-2189 is a dupe of this one.

Cameron McCormack, 30 Aug 2011, 04:14:50

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