I'm not sure I understood it completely,
so first I'll how I see it from your description.
You have a list of items to display,
you have maxItems to display per page,
you only want to show some items based
on their state.
Your division of responsibilities is putting too
much into one place and causing problems.
I'm not a MVC freak, but I belive you can apply it here to avoid the
problems above,
your data is list of facets.
you skiiped model part and put data directly into view...
add a model that will be aware of the data and return count by
counting only facets that should be displayed.
model when asked for items should return only those that are visible,
this way your View component can handle paging without being aware
of the filter applied to the data.
Davor Hrg
On Dec 4, 2007 6:42 PM, Britske <[EMAIL PROTECTED]> wrote:
>
> I quickly solved it with some kind of hack for those interested, but I'm
> still curious if the kind of binding I described is possible at all.
>
> Cheers,
> Geert-Jan
>
> A hack that's working:
>
> introduced 2 extra fields: facetmaxInc and FacetOld;
>
> public void setFacetCounter(int facetCounter)
> {
> this.facetCounter = facetCounter;
> if(facet!=null && facet.equals(facetold))
> {
> facetMaxInc = facetMax;
> facetold = facet;
> }
> if(facet!=null && facet.getFacet().isSelected())
> {
> facetMaxInc++;
> }
> }
>
> and check on facetMaxInc.
>
>
>
> Britske wrote:
> >
> > I need a bit of introduction to lay down the problem, so please bare
> with
> > me:
> >
> > I have a component which renders lists of items. A parameter
> > (childcounter) keeps track of the number of rendered items in the
> current
> > List.
> >
> > I have the requirement. to be able to define on a per-page basis how
> many
> > items are rendered at max. I implemented this by simply binding
> > childcounter param and checking it against a field (say: maxitems) on
> the
> > page. Depending on that I can decide on a per-page basis what to do with
> > items that exceed the maxitems-threshold. (render different blocks, etc)
> > So far so good.
> >
> > Currenly Im using this component to render facets
> > (http://en.wikipedia.org/wiki/Faceted_classification) as part of a
> > navigation menu. The requirement is to (for each list) render all
> SELECTED
> > facets first and then render x (say 5) UNSELECTED facets per list, where
> x
> > is defined by maxitems.
> >
> > The problem:
> > the component doesn't know (and shouldnt know) that it is rendering
> > facets. So it doens't know if a facet is selected or unselected. Based
> on
> > that the childcounter is incremented each time a selected or unselected
> > facet is rendered, and the maxitem-treshold is reached when 5 facets per
> > group are rendered (independent whether they are selected or
> unselected).
> > Obviously thats not what I want.
> >
> > The solution (so I thought)
> > 1. The component doens't know that it's rendering facets, but the page
> > knows. Moreover, the component outputs the item that it is currently
> > rendering. (the facet in this case).
> > 2. the param childcounter of the component is bound to the page field
> > 'facetCounter'
> >
> > since as I understand it a param-binding is bi-directional I did the
> > following:
> >
> > Page:
> > --------------------------
> > @Component(parameters = {"result=facetdsText",
> > "row=gGroup","childrow=facet","ulClass=literal:facets",
> > "childcounter=facetcounter"})
> > private CompositeFlexLi facetBlock;
> >
> > public void setFacetCounter(int facetCounter)
> > {
> > if(facet==null || !facet.getFacet().isSelected())
> > {
> > this.facetCounter = facetCounter;
> > }
> > }
> >
> > What it does is obvious:
> > 1. the component renders and updates childcounter, which in effect calls
> > setFacetCounter(int facetCounter), since its bound to facetCounter.
> > 2. facetCounter is only updated when the current item is a UNSELECTED
> > facet (which it knows in contrast to the component)
> >
> > The actual problem now is that facetCounter indeed is only updated when
> a
> > facet is unselected, but the parameter 'childcounter' is still updated,
> > although it is bound to the field facetCounter which is not updated
> (they
> > aren't in sync).
> > The behavior now is the following: (say i have 2 selected facets)
> > childcounter: 1,2,3,4,5
> > facetfield: 0,0,3,4,5
> >
> > while i figured it would be:
> > childcounter: 0,0,1,2,3,4,5
> > facetfield: 0,0,1,2,3,4,5
> >
> > Was I expecting to much 'binding-magic' to happen here, or am I missing
> > something?
> > If not, what would be your suggestion to tackle this issue? (making the
> > component aware that its rendering facets is as I explained no option)
> >
> > Thanks in advance,
> > Geert-Jan
> >
> >
> >
>
> --
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