HTMX

This is part three of a series of articles looking at HTMX in Drupal. Last time I looked at using HTMX to run a "load more" feature on a Drupal page. Before moving onto looking at forms I thought a final example of using HTMX and controllers to achieve an action.

One of the key examples that helped me understand HTMX was when it was used to create a tabbed interface, without reloading the page. This was quite simple to recreate in Drupal and can be done in a single controller.

In this article we will be creating a tabbed interface in Drupal, where HTMX is used to power loading the data in a tab like interface without reloading the page.

All of the code contained in this article can be found in the Drupal HTMX examples project on GitHub, but here we will go through what the code does and what actions it performs to generate content.   

Following on from my last article, an introduction to HTMX in Drupal, I wanted to start looking at examples of HTMX being used to power interactivity in Drupal in different ways.

I thought a good place to start this off would be to look at using HTMX in a simple controller. By creating a route to a controller we can render content and then inject HTMX attributes to perform actions with the same controller.

In this article I will put together a controller action to load some pages of content to display them as a list. An element containing HTMX attributes will be used to make a request back to the same controller action and generate more items in the list. These new items will be appended to the existing list along with another element containing HTMX attributes that we can use to request more items.

HTMX is a JavaScript library that allows you to make ajax calls and create CSS transitions without writing any JavaScript code. It works by adding attributes to HTML elements, which it then uses to set up and perform ajax requests, swap elements, and a few other things.

It was added to Drupal in version 11.3.0* and gives developers the ability to create interactive elements using render arrays and HTML attributes. The intent is to replace the entire ajax sub-system with one built around HTMX, and there is quite a lot of work ahead to accomplish this task.

* Technically, HTMX has been in Drupal since 11.2.0, but only as an experimental library. Drupal 11.3.0 features the full HTMX library and a number of helper classes to make life easy.

HTMX is a JavaScript library that can be used to issue AJAX requests, create CSS transisions, and set up web sockets using HTML

The power of HTMX is that it can be used without writing any custom JavaScript code. It works by looking for attributes in HTML tags using that information to set up events, user interaction, and send requests to a back end. The system is backend agnostic and so will essentially work with any system that can accept, interpret, and respond to the requests.

I have been meaning to look at HTMX since hearing about as it seemed like a decent system with a good community. Since then it has been included into Drupal 11.2.0 and there are plans to make it the core system for AJAX requests going forward. As a result it has jumped forward in my list of things to look at.