Re: Repeats and events

What do we do for setfocus?

On 12/12/2011 03:48 PM, Erik Bruchez wrote:
>
> All,
>
> I have a question about repeats and events, which I am not sure is
> addressed in the spec (at least not explicitly).
>
> In XForms 1.1, there is the concept of "repeat objects" which
> represent runtime repeat iterations. XForms1.1 states:
>
> "A repeat object is an implicitly generated group element that
> contains the set of run-time objects generated to represent the repeat
> template content for a single repeat item of the repeat collection.
> These run-time objects are form controls, XForms actions and other
> host language elements that correspond to elements in the repeat
> template."
>
> Less formally, XForms 1.1 also mentions the "repeat container"
> control, which manages the "repeat collection".
>
> Now, let's say we have this repeat with a nested event handler:
>
> <xforms:repeat ref="value" id="my-repeat">
> <xforms:action ev:event="my-event"/>
> </xforms:repeat>
>
> And I dispatch, from outside the repeat, an event using the repeat id:
>
> <xforms:dispatch targetid="my-repeat" name="my-event"/>
>
> The three-pronged question is:
>
> 1. Does the handler run, or not?
> 2. If so, does it run once, or once per repeat iteration?
> 3. If it runs only once, in which XPath context does the action run?
>
> There seems to be 2 basic options:
>
> Option A. If you assume that the id corresponds to the repeat
> container, then it should not respond to the event, as the actual
> markup would look like:
>
> <xforms:repeat ref="value" id="my-repeat">
> <xforms:group ref=".">
> <xforms:action ev:event="my-event"/>
> </xforms:group>
>     ...
> </xforms:repeat>
>
> Option B. However, if the id corresponds to the repeat iteration, then
> it should respond to the event, as if you had written:
>
> <xforms:repeat ref="value">
> <xforms:group id="my-repeat" ref=".">
> <xforms:action ev:event="my-event"/>
> </xforms:group>
>     ...
> </xforms:repeat>
>
> Further, in the latter case, the event handler would run in the XPath
> context of the iteration with the current repeat index.
>
> There are benefits and drawbacks to each option. Option A makes sense
> once you explain to the programmer that even though he can't see it,
> there is a virtual <group> in between. However, this doesn't allow
> placing within xforms:repeat a handler that responds directly to an
> event directed to that repeat by id.
>
> Option B makes sense in that if you just look at the markup, it might
> be more intuitive that a handler responds to an event directed to that
> repeat by id. On the other hand, it makes making a distinction between
> events targeting a repeat iteration vs. the repeat as a whole more
> difficult.
>
> Is there an option C?
>
> -Erik
>