WordPress 3.5 media_order Issue Affects Custom Galleries
The revamped Add Media interface in WordPress 3.5 improves a great many things about media management. It’s fantastic and thanks go out to the team for all the hard work!
Unfortunately, the removal of a visible menu order field and the associated “Sort by Ascending / Descending” links has created an issue that affects some plugins and themes.
For instance, I often code templates that detect all images attached to a post and display them in a slideshow. In these cases I rely on the menu_order field to set the image order. Here’s a line I use often:
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I’ll walk through the steps that illuminate the issue. First we’ll create a new post and upload a bunch of images to it. Using the “Uploaded to this post” filter, they appear to be in the correct order…
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When we look in the DB, we see that their menu orders are actually all “0”. As we will see, this has some funny effects.
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We close the Media Upload window and continue our work. When we return to the Media Upload screen, the image order appears to have been reversed.
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Now, at this point there’s been no actual change in the DB. But it’s not unreasonable for the user to be a bit confused, and to manually make a change to the order. Here I’ve dragged the 01 image to the first spot:
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When I do this, WordPress finally assigns a non-zero order to all of these images. Unfortunately, the order being assigned is the same (backwards) order that we are seeing via the interface.
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As you can see, “image02” has been assigned a menu order of 25. To properly reorder the images involves manually dragging and dropping, which can be quite onerous with large image sets.
See: http://core.trac.wordpress.org/ticket/22758
Posted January 2013