Ditto and AtoZ (Solved)

I have a problem to make document output by alphabet. Letter buttons must be active only in case the documents are on this letter filter.

Header buttons: ALL | A | B | C | D | ... | Z

-----
Document tree

Makers (49)
Maker1
Maker2
...
ABC (109)
A
B
C
...
Z

Template
-----
<!-- Header
<ul class="abecele">
<li><a href="[~[*id*]~]">ALL</a></li>
[!Ditto? &id=`abc` &parents=`109` &tpl=`abecele` &sortBy=`pagetitle` &sortDir=`ASC`!]
</ul> -->

<!--Catalog output
<ul class="abecele">
[[Ditto? &parents=`49` &tpl=`makers` &sortBy=`pagetitle` &sortDir=`ASC` &paginate=`1` &extenders=`request` ]]
</ul> -->
-----

Chunk - "abecele"
<li><a href="[~[*id*]~]&ditto_filter=lastname,[+pagetitle+],11">[+pagetitle+]</a></li>

Chunk - "makers"
<li><a href="[~[+id+]~]">[+lastname+] [+name+]</a></li>

-----

All works except active and inactive alphabet button links.
I’ve tried to make "abecele" chunk:
[+phx:if=`[+total+]`:is=`0`:then=`<li>[+pagetitle+]</li>`:else=`<li><a href="[~[*id*]~]&ditto_filter=lastname,[+pagetitle+],11">[+pagetitle+]</a></li>`+]


But it doesn’t work, any suggestions?

The following is a comprehensive tutorial how to build letter index with active/inactive letter-buttons depending on actual presence of documents in container(s) being the subject of interest/search.

Prerequisites are three chunks, for example, named: "empty", "one-letter", and "index".

"empty" chunk is used for generating empty output -- its content should be something like:

where [+none+] stands for non-existent TV name which, at a runtime, will be replaced by Ditto with empty text.

"one-letter" chunk is used for generating listing of documents whose filtered TV (lastname in the above-post) starts with specific letter, its sample content might be as follows:


"index" is used for generating A B C... Z active/inactive buttons, I will build its content at the end.

You need to put into content field of each A, B, C, ..., Z document Ditto call:


Next you need to build A B C ... Z index in your ABC document; for this purpose place into the content of this doc the following Ditto call:


And finally, "index" chunk, the most sophisticated part of this task:

Of course, the above only looks like a sophisticated thing, but actually it is a simple if-then-else statement expressed in PHx terms. Before building each letter-button in the index, you need to check whether documents starting from this letter exist or not. This part is performed by if-part of PHx. If Ditto returns no output (there are no documents), then the letter as a static text is rendered (then-part of PHx). Otherwise (else-part of PHx), linked letter is rendered. Done.
The advantage of this solution is that it requires neither extender nor ugly-looking url stuff.

Edit: this was a long post so some inconsistencies appeared in it, but hope I removed them all.

Thx man, respect!!!
For this moment there was no any working solutions (snippets or plugins) for this task, but now it is.

Hi Labasus,
nice to hear that it works for you. Please mark the thread as "solved" or so thus signaling for others that it comprises working solution.
(In my spare time, I will copy document structure from your post and put this tutorial onto my site where I am collecting the most interesting solutions provided to this forum.)

Hey alik,

thanks for the how-to!

For this moment there was no any working solutions (snippets or plugins) for this task, but now it is.

...would the a2z Snippet be an alternative for this? http://modxcms.com/forums/index.php/topic,36667.msg221349.html#msg221349