Re: Styling based on instance data

I'm not sure a simple on/off is powerful enough. If a solution is to be 
found it should be capable of handling as many situations as possible.
Consider a form as below but where you want the colour to reflect the 
degree of overdueness, and that degree should be expressed as a 
calculated rgb value that directly correlates to the number of hours 
overdue (shading darker or redder or whatever). Its not a great example 
but you get the idea - someone is going to want to use a calculated or 
otherwise broad range of values for this stuff. Is there a way to modify 
the css at runtime?
maybe something like:

   <style type="text/css">
     :mip-overdue-on { color: <xf:value-of bind="@due"/> ; }
   </style>

or maybe relying on css for all the stying options is just asking too much.

Jason.

Mark Birbeck wrote:
> 
> Hi Roland,
> 
>> I would agree that there are cases where styling dependent
>> on the value would be useful. A situation I have encountered is the 
>> need to style
>> negative numbers differently to positive numbers.
> 
> We could still keep this as styling based on 'state' though, with
> negative and positive being different states. Myself and Paul Butcher
> (one of my colleagues) tested to see if a generic solution based on
> state was workable, and found that it probably could be done.
> 
> I'll try to find the details, but it essentially went like this; if
> you think of the MIPs, such as relevant, readonly, and so on, they all
> control a pair of events and a pair of CSS pseudo-classes. To make
> this generic all we need is a way to describe these two pairs.
> 
> So lets say that we have a system that has a business rule concerning
> whether a library book is overdue or not; we know that we'd like a
> pair of events called "xforms-mip-overdue-on" and
> "xforms-mip-overdue-off", say, and we'd also like some pseudo classes
> like ':mip-overdue-on' and ':mip-overdue-off' to allow us to style
> data that is in this state. By making the names of the events and
> pseudo-classes follow a clearly defined pattern, we could just use a
> single attribute to specify the whole thing:
> 
>  <style type="text/css">
>    :mip-overdue-on { color: red; }
>  </style>
> 
>  <xf:bind nodeset="books/book" overdue="today() &gt; @due" />
> 
> It's probably not a good idea to allow any old attribute on 'bind', so
> one possibility would be to put these 'soft MIP' attributes into a
> different namespace:
> 
>  <xf:bind nodeset="books/book" mip:overdue="today() &gt; @due" />
> 
> Any attribute in this namespace would be treated as a 'soft' MIP, and
> the events and pseudo-classes created accordingly, with the default
> names.
> 
> There are other ways to express the mark-up, but I'd have to dig up
> some of the (very old) notes that myself and Paul made to recall the
> ones that we came up with. I do remember that we played with having a
> new element that defines the names of the events and pseudo-classes,
> but that may be more powerfull that is needed.
> 
> Anyway, I thought it worth posting these thoughts since they might
> spark some ideas amongst others.
> 
> Regards,
> 
> Mark
>

Received on Saturday, 2 December 2006 01:07:18 UTC