Saturday 30 March 2019

Hide Pagination if one page results - Oracle APEX

I love this period of development not long after an APEX upgrade, where I discover all these little improvements that will help us out. Stuff that's not quite noteworthy in the wonderful read that is the new features guide (that's not sarcasm. Read it. Now.)

Recently I made an observation regarding a handy new template option, one that hides pagination if there is only one page of records. I've had a bit of jQuery doing this for a while, and I thought I had blogged about it already, but it was a similar feature regarding no data found.

Sure enough, it was still sitting in an email labelled 'blog post'. Now I could write this off, like quite a few others where a built-in feature got released before I got around to writing up a post. But I decided to post about this one anyway, in part because it may take some time for some to reach 18.2, and I think it's part of an interesting conversation regarding the evolution of the product.

Some of the improvements in each APEX release are likely the result of
- a tweet about a feature
- a forum post asking about a quirk
- a conversation at a conference, likely while at least one person was holding a beer
-  a request on

If you notice something odd, or think something you've done would help everyone, put it out there.  Chuck it on the forum. Make it your first blog post. You'll help the community, and reap the benefits yourself when the time comes to upgrade to that version with some delicious fruit.


So, that being said, here was the template option, available in APEX 18.2, but only to existing applications only after refreshing your theme.

Classic Report Region Template Option

Applied to a classic report, it will hide certain pagination styles with there is less records than that specified per page on that report.

This will save me creating a dynamic action on the region, calling a small bit of jQuery I have in a library. It's also something I figured could be practice for turning into a plug-in, but I never got there, either.

The trouble is, this template option doesn't appear to work with my favourite pagination type (another reason for the post).

I like to use the Search Engine pagination style, on the top left - available to the user regardless of vertical/horizontal width of the region. I have chapter in my book describing how to turn standard HTML links in this search engine pagination for a legacy theme into buttons.

Trouble is, it seems a little superfluous when there's only one page of results. And it takes up vertical space. Hence the idea of the template option.

With a little JavaScript invoked in a dynamic action after refresh on the region - this is the default dynamic action when you right-click to create dynamic action on a region in page designer. Kudos to the APEX developers responsible for those little touches.

Here's the code I used to do the job.
if ($(this.triggeringElement).find('.t-Report-paginationText').children().length == 1
  && $(this.triggeringElement).find('.t-Report-paginationText').children().text() == 1)
A few points:

  • this.triggeringElement refers to the region, since that's what the dynamic action is firing off
  • find() is looking for page elements with the t-Report-paginationText class, in this case, the button group
  • children() counts how many buttons, so true if there is only one
  • I added the second condition when I realised it was hiding results when there were 11 pages of results, so I check if the button contains the text "1"
  • then it applies .hide() to the pagination group

Note, this is designed for Search Engine pagination in the Universal Theme, and the template option probably works with a different mechanism. There might be a clever way to solve this with CSS?

The real solution also belongs in a library so it can be re-used. I did it like this once, but I'm sure it could be neater.
function hide_pagination_iff_one_page (p_region) {
  if ($('#'+p_region+' .t-Report-paginationText').children().length == 1
  && $('#'+p_region+' .t-Report-paginationText').children().text() == 1)
    $('#'+p_region+' .t-Report-pagination').hide();
I would then put this in the after refresh dynamic action. It passes the ID of the region triggering the action, ready for embedding in the selector.

So my open question is, how would you tidy such JavaScript? how would you place it in a library?
I'm still getting the hang of namespaces, and how to organise our stubs.

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