frontend category filtering set in backend?

In the past week I've tried just about every CCK for Joomla I could find, and found that FC seems the best balance between capability and user-friendliness available for free. But I am not sure if I can get it to do what I want.

What I would like to do is to have a menu link to a category with a filter.
I know frontend filtering can be enabled, by enabling this both for the field and for the category. But I would like to set the filter in the backend, without actually enabling user filtering in the frontend.
So I would like a text field in the backend category settings where I can fill in a condition that will be used to filter the category before it is displayed in the frontend.
Also, the filtering condition that I need is the value of a custom field (<0 or >0 to be precise). So text filtering like it is on the frontend would not be enough.

I think more people would like this. It would be a way for example to show items in a category with a certain price range, size or other custom field property.
In my case, I want to use it to filter dependent on whether content items have votes or not according to my custom field. Like that I can have an overview of hot items as well as an overview of new items that does not include items already listed as hot.

Would something like this be possible?

I wouldn't mind doing some experimenting myself, but I'd need a little guidance from the experts as to what parts of the code I should review and modify.
I think the xml file would need to be changed, with an extra box to input a filter and perhaps an extra checkbox allowing frontend activation of backend filter input. But for the remainder I'm still in the dark...

Any suggestions would be much appreciated!

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Not an easy code fix/patch.

FilterSets
There is a feature in the roadmap called FilterSets.
This is a pre-configured set of filters.
I do not know at this point exactly how this is going to work.
But this will probably do what you are trying to do. (eventually)

Search Parameters
In another component I used to put the "filters" in a search URL as a search parameters. Then this URL was used in the menu to display the filtered search results page.
Right now I do not know if it is currently possible to pass any specific custom fields filters via the URL. Don't think so. This feature has to be supported by the component search functions.

So at this point I do not see any easy way to do this.

Maybe someone else will have some other ideas.


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