Posted by NumerousHats on Mon, Apr 07, 2025 - 5:22am --- Updated: Apr 08 '25 - 7:18am

[NB: Title is changed, originally was "Duplicated images in Mosaic Grid view". Changed due to  the problem not really being with Mosaic Grid.]

I'm not sure if this is a bug in the Mosaic Grid module, or if I've misconfigured something. It seems that if I have a Mosaic Grid view linked to a node via a contextual filter and relationship, then the images in the field being displayed by the Mosaic Grid are shown multiple times (see screen shot below).

Here is how to reproduce the problem in the backdropcms.org sandbox:

  1. Add a field to content type "Page" called "Images" of type "Image" and allow an unlimited number of values.
  2. Hide that field from the default display.
  3. Install and enable the Mosaic Grid module.
  4. Create a block view of format "Mosaic Grid" displaying the "Images" field. Add an "Nid" contextual filter with setting "Provide default value" of type "Content ID from URL" and a relationship to "Content: Images (field_images:fid)" with the "Require this relationship" box checked (based on an answer to my recent previous forum question -- I actually don't fully understand what that last bit is doing...)
  5. Add that block view to the "Content" region of the default layout.
  6. Create a new page and add the three default "card" images to the "Images" field.

The result is that I see the three card images repeated three times:

If I remove the relationship in the view, then everything is as I expect:

Removing the relationship is apparently not an option in my use case, as the "Images" field (or its equivalent) may have no content. In that case, I don't want the views title to show, and it seems that not having the relationship causes the views title to appear even if the view has no results (which was the subject of my previous forum question).

If my setup seems correct, I will be happy to open an issue in the Mosaic Grid repo on Github.

Accepted answer

Maybe "Query settings" : "Distinct".

If there are multiple identical items, each will be displayed only once. You can use this to try and remove duplicates from a view, though it does not always work.

Comments

Mon, Apr 07, 2025 - 5:40am by NumerousHats

For completeness, here is what my views setup looks like:

Mon, Apr 07, 2025 - 6:27am by Enthusiast

The Relationships is not needed in this case. Your View simply gets a field from the current page, so Contextual Filter is enough. If the field has no images, the block should not be displayed and the Relationship has nothing to do with it. 

I made many sites on Drupal, less on Backdrop, but I have never encountered an display empty Views block if there is no data in it. This is normal behavior by default, without any settings, as the guys wrote in a previous topic.

Switch Mosaic Grid to a simple output of fields, and you will see, I am sure that, Mosaic Grid is not guilty.

Mon, Apr 07, 2025 - 2:45pm by NumerousHats

Except that's not what I'm seeing.

Here are screen shots using the same sandbox instance from the time of my original post, except that I have removed the relationship in the view, and I have added an additional Page node with no images in the "Images" field.

Page node with images:

That looks correct.

However, here is the Page node that doesn't have any images in the "Images" field:

As you can see, the view block along with the view title ("Image mosaic") is still there. There is even a set of nested view <div>s, the innermost of which is empty:

 

Mon, Apr 07, 2025 - 3:10pm by NumerousHats

If I put the relationship back, the empty block disappears:

(with the side effect that the other node now has 9 images instead of 3).

Again, I have no understanding of what is going on here or what is causing it, and I would welcome any enlightenment that anybody can provide.

Mon, Apr 07, 2025 - 5:09pm by NumerousHats

Oh, and I tried your suggestion to get rid of Mosaic Grid. I changed the view format to "Unformatted list", and you are absolutely right, there are still 9 images when the relationship is there:

So it indeed has nothing to do with Mosaic Grid, and I will see if I can change the title of this post to reflect that.

Changing the format has no effect on the behavior of the node with no images: removing the relationship still results in a block with a title and no content.

Tue, Apr 08, 2025 - 5:49am by Enthusiast

I am surprised, but I confirm that the block and the title are displayed when there is no content. And the "No Results Behavior" option, which should display a message about an empty result, also does not work. Backdrop CMS 1.30.2

A little later:
But the Filter solves this problem. 
Why didn't I think about it before!?. OMG! Disgrace...

Tue, Apr 08, 2025 - 8:20am by NumerousHats

Excellent! Yes, that's one of those "too simple and obvious" solutions. I hadn't thought of it either.

However, this solves only one part of the problem (empty blocks). It doesn't solve my original problem -- I still see multiple copies of the images:

(I've made things easier by making them thumbnails).

Tue, Apr 08, 2025 - 8:59am by Enthusiast

Maybe "Query settings" : "Distinct".

If there are multiple identical items, each will be displayed only once. You can use this to try and remove duplicates from a view, though it does not always work.

Tue, Apr 08, 2025 - 11:17am by NumerousHats

YES! That works.

This whole thing is extremely bizarre, though. On the site I'm building (not the sandbox demo), I had a view that was displaying multiple images correctly (i.e. once, not duplicated N times). I added the "not empty" filter, then suddenly it started showing the images duplicated N times.

It seems that "Query settings: Distinct" solves that. We'll see. I've been round and round on this enough times that I don't trust anything to keep working...

Tue, Apr 08, 2025 - 8:38am by NumerousHats

If there are N images in the field, then that set of N images gets repeated N times, it seems.