Re: ISSUE-73 (Overlap of "predefined vocabularies" with other specifications), was: Concerns about new section "predefined vocabularies"

On Jul 16, 2009, at 1:35 AM, James Graham wrote:

> Ian Hickson wrote:
>
>> Do we want to drop support for dragging contact information from  
>> the Web to native apps just so that we can change which spec holds  
>> what? That seems weird. (We could split the sections out and have  
>> bidirectional normative references instead, but that seems to  
>> defeat the point of extracting the sections.)
>
> That does seem unfortunate but it could also be solved (in a more  
> flexible way) by native apps getting support for the HTML5 microdata  
> format. Obviously this is less than ideal since it means that many  
> native apps would have to be updated compared with relatively few  
> browsers. However it may be good enough as a first step. I think it  
> is only a critical problem if DnD to native calendar/address book  
> apps is seen as the killer feature of microdata. Otherwise it seems  
> reasonable to leave this out initially (i.e. for HTML5) and add  
> support for it if it is needed (and implementors seem interested)  
> later.

First, browsers are free to add additional types when dragging from a  
Web page to a native app. So it's not like browsers can't do this  
without the built-in vocabularies. In fact, I'm not even sure the  
HTML5 spec *should* be defining what happening when you drag from a  
Web page to an app.

Second, the HTML5 spec itself could have hooks for separately defined  
microdata vocabularies that let them define additional UA requirements  
for drag formats. So I don't think bidirectional normative references  
would be required to normatively require this feature, if so desired.

Third, drag and drop is not exactly the most convenient or  
discoverable way to extract address data. When I get an email with a  
vCard included, the way I add it to my address book is by clicking on  
it. Launching the address book app first and dragging would be a lot  
less convenient. I would hope my browser could give a similarly nice  
UI. On mobile platforms, there's often not even a notion of dragging,  
or of dragging between apps. So I think it's probably jumping the gun  
a bit to define the UI for transferring a vCard to the system address  
book. Also, drag and drop as the sole way to perform an action tends  
to be bad for accessibility. This is probably an area where UAs will  
want to experiment.

For these reasons, I think it's probably not so great to define a  
specific UI path to extracting address info in the HTML5 spec.

Regards,
Maciej