Front-end filtering

Thanks for your interest and for this question (there are no silly questions). The topic has come up in some earlier support topics:

Building an archive gallery with MLA

Pagination Revisited

template query for att. tags

The earlier topics deal with adding or modifying PHP code in WordPress Template files. This gives you a lot of power, but you’ve got to write some code.

If you have a stable set of tags or categories, you can do the whole job in a simple page or post, without any PHP code. Here is an example:

Please select an Attachment Tag value:

<form id="attachment-tag-form" method="get" action="">
	<select name="attachment_tag" class="postform">
		<option value="">-- Select a Value --</option>
		<option value="california">california</option>
		<option value="boden-canyon">Boden Canyon</option>
		<option value="another">another</option>
	</select>
	<input type="submit" id="submit" name="submit" value="GO">
</form>

[mla_gallery post_parent=all attachment_tag="{+request:attachment_tag+}"]

You can enter this if you select the “Text” tab in the Edit Post/Page screen ( V.S. the “Visual” tab). Look for it in the upper-right corner of the content editor section.

The form gives you a drop-down list of tags (or categories or whatever). The value= part must be the name/slug of the term; look at the “Boden Canyon” option.

When you select a value and click the “Go” button, the selection is added to the post/page URL and the page is re-fetched. For example, on my test system the new URL is:

https://mladev/attachment-tag-archive-request/?attachment_tag=boden-canyon&submit=GO

In the [mla_gllery] shortcode you can see how the parameter is used to select images for the gallery; attachment_tag="{+request:attachment_tag+}". The attachment_tag= portion gives the name of the taxonomy you want (attachment_category works, too). The "{+request:attachment_tag+}" portion copies the value of the attachment_tag argument of the URL from the $_REQUEST array to the parameter value.

That’s the short answer. You can use the < form > and {+ request: +} idea to make all sorts of gallery controls available without resorting to HPP coding of your own.

I am thinking of adding some widget and tag-cloud support in a future version of the plugin; questions and comments like yours are a great source of motivation and information.

I’m going to mark this topic resolved, but please add to it if you have any problems or further questions. Thanks again for your interest and for the question.

Brilliant, that looks like it will work perfectly.

One more quick question, is it possible to select multiple tags from different drop-down boxes? Is it as simple as repeating that select loop? Or repeating the form and somehow placing the ‘submit’ bit after it?

Thanks very much for your quick and detailed response. It looks like a great plugin.

Thanks for the update and the kind words.

The quick solution for your multiple tags question is to add a second select element, as you suspected:

Please select an Attachment Tag value:

<form id="attachment-tag-form" method="get" action="">
	<select name="tag1" class="postform">
		<option value="">-- Select a Value --</option>
		<option value="california">california</option>
		<option value="boden-canyon">Boden Canyon</option>
		<option value="another">another</option>
	</select>
	<select name="tag2" class="postform">
		<option value="">-- Select a Value --</option>
		<option value="california">california</option>
		<option value="boden-canyon">Boden Canyon</option>
		<option value="another">another</option>
	</select>
	<input type="submit" id="submit" name="submit" value="GO">
</form>

[mla_gallery post_parent=all attachment_tag="{+request:tag1+},{+request:tag2+}"]

There’s another solution, but it will require an MLA enhancement before you can us it. The HTML Select tag has a “multiple” attribute:

HTML < select > multiple Attribute

You could re-code the example as:

<select multiple name="tags[]" class="postform">
	<option value="">-- Select a Value --</option>
	<option value="california">california</option>
	<option value="boden-canyon">Boden Canyon</option>
	<option value="another">another</option>
</select>

The multiple name="tags[]" portion of the tag says “allow multiple selections and put them in an array called tags”. Sadly, I hadn’t thought about arrays when I wrote my plugin code, and this doesn’t work in the current MLA version. I will add this in my next release.

Finally, you could include a simple text box and let people type in a list of terms, separated by commas. Of course, they’d have to know the term values…

However you handle multiple selection, remember that the default behavior is to match any term in the list (i.e. join them with OR). You can use the tax_operator and tax_include_children parameters to change the defaults. See the Settings/Media Library Assistant screen, Documentation tab for details.

Thanks again! It’s working nicely for me now. I look forward to the multiple selection implementation too.

One other quick question…
I’ve got two galleries on one page, the first, ‘Latest Photos’ is a paginated gallery of all photos, sorted by date descending. The second gallery, ‘Search Photos’, has the search form as above, and is initially blank as I’ve used the ‘AND’ tax_operator to only retrieve photos that match the selected tags.

Is it at all possible to combine these into a single gallery? So all photos are shown initially, and are then filtered by certain tags. Essentially, I’d like all photos (or all tags) to be shown for a start, before being filtered by tags using the ‘AND’ tax_operator.

If it’s not possible, is there any way to hide pagination on the search gallery until the results are returned?

Cheers!

I’m happy to hear you’re making progress.

I can’t think of any way to accomplish your latest goal without resorting to some straightforward PHP coding and WordPress Template composition. To get an idea of what’s required, have a look at this recent support topic:

Show main category with list inside

Look at the last post in that topic. The details are different, but the overall idea is that same. You would do some pre-processing of the query arguments and then use do_shortcode to call [mla_gallery] with the parameters you need to get the results you want. You can use the multiple selection attribute, remember the selected term(s) from page to page, etc. without too much trouble.

If you’re willing to do some PHP work, try composing a variation of the solution in the above topic for your page. Let me know if you have any problems or further questions.

I have released v1.60, which corrects the problem of handling arrays such as those generated by the “multiple” version of the HTML Select tag.

When you get a chance to upgrade and test it out, let me know if you have any problems or further questions. Thanks for your interest and for your patience.

Hi again David,
I’m finally getting a chance to re-visit this project. Thanks again for your ongoing support!

At some stage I hope to sit down and learn php, but for now it’s a bit daunting to do what you suggest above. Instead, is it possible to simply have my search form on one page, and the search results displayed on another? So when I someone clicks ‘go’ it takes them to the new page with the gallery of selected photos. I’m sure I read how to do this somewhere but can’t find it for the life of me!

Good to hear from you! It’s straightforward to send the results of your search form to another page; simply fill in the URL of your landing page in the form’s action field. For example, here is a variation on the “two tag” form from an earlier post:

<form id="attachment-tag-form" method="post" action="/tag-archive-request-results-page/">
Tag 1:
	<select multiple name="tag1[]" class="postform">
		<option value="california">california</option>
		<option value="boden-canyon">Boden Canyon</option>
		<option value="another">another</option>
	</select>
<br />Tag 2:
	<select name="tag2" class="postform">
		<option value="">-- All Tag Values --</option>
		<option value="california">california</option>
		<option value="boden-canyon">Boden Canyon</option>
		<option value="another">another</option>
	</select>
	<input type="submit" id="submit" name="submit" value="GO">
</form>

The < form > tag has action="/tag-archive-request-results-page/", which names the permalink of the page/post that will be called with the search form results. The first of the two < select > tags uses the multiple attribute, which is now working in MLA. The first < option > in the second < select > tag has an empty value, so it won’t participate in the “AND” logic unless you make a different selection in the dropdown list.

I hope that answers your immediate question. When you’re ready to tackle PHP and a more sophisticated solution, post an update here. Good luck with your application and thanks for your continued interest in the plugin.

Hi David,
Thanks very much, that worked perfectly. I’ll re-visit the php option eventually, but I’m really happy with how it’s working at the moment. I’ve tagged over 2000 photos with your plugin so far and have thousands more to go! I’ll be taking the site live in the next couple of weeks hopefully, so will forward you the link when it’s done!

Cheers!
Chris