DrupalCon Barcelona 2015: Drupal 8 theming
Channel: Drupal Association
Date: 22/09/2015

Full disclosure: this session was given at DrupalCon in LA, the session will be updated & modified to match the state of Drupal8 in Barcelona (RC1 i hope) - slides are added from LA as well to give the track chair an idea of the session

Drupal 8 has many new exciting features, but none are as radical or as needed as the changes made to the theme system*!

For 10 years Drupal's front end was design and built by developers that tried their very best to figure out what the front end needed; the lack of dedicated front-enders in core; resulted in front end architecture that was "less than ideal" for the challenges that the front end has faced for the last 5 years.

Drupal 8 and twig changed it all!

A complete overhaul of the theme system started 3 years ago - PHPtemplate is now out the door, the twig template system is implemented, and most importantly, the core idea of how the front end is build has done a 180° from how Drupal 7 handled theming.

This means:

No more divitis
No more Class soup
No more of Drupal's standard markup and classes
No more yelling at the markup and not knowing where stuff came from
No more using regex for modify a CSS class!
Such a dramatic change would normally cause panic is a time for celebration.

The session will give you a solid understanding of the key concepts of Drupal 8 theming, as a themer.

We will cover:

The structure of a Drupal 8 theme
Classy and Stark themes (and  what it means for the future of theming)
Base themes - what happened
Debugging and looking for markup
How {{ twig }} works from a CSS/HTML coders perspective (how to build a theme)
What to tell your developers about theming
CSS file structure and how M.A.T. works
JS and how to drop 32K
This session is created with the themer / front-ender / html-css designer  in mind, so a maximum of 3 lines of PHP will be shown in this session.

*Yes I know that a lot of “big things came into d8” that weren't front end related ;)