Move classes out of the preprocess functions and into the Twig templates. Use the addClass() attribute method to add classes in the template. Use the clean_class filter to filter class names, if necessary. Maintain all existing functionality and ensure all existing class names are still in the markup, even ones that are inherited.

See the following issues for more detailed examples:
#2217731: Move field classes out of preprocess and into templates
#2254153: Move node classes out of preprocess and into templates

See this change record for information about using the addClass() method:
https://www.drupal.org/node/2315471

See this change record for more information about the phase 1 process of moving class from preprocess to templates:
https://www.drupal.org/node/2325067

Preprocess Functions Modified

template_preprocess_page
views_preprocess_page
bartik_preprocess_page
seven_preprocess_page

Twig Templates Modified

page.html.twig
bartik/templates/page.html.twig
seven/templates/page.html.twig

Comments

davidhernandez’s picture

davidhernandez
Primary language English
Location USA
CreditAttribution: davidhernandez commented
Issue tags: +FUDK
mortendk’s picture

mortendk CreditAttribution: mortendk commented
Issue summary: View changes

the classes for the maintenance pages is only affected on the body tag - so i suggest we move that to html patch instead #2329753: Move html classes from preprocess to templates
i have updated the issue

davidhernandez’s picture

davidhernandez
Primary language English
Location USA
CreditAttribution: davidhernandez commented

Did you move them to the other issue?

mortendk’s picture

mortendk CreditAttribution: mortendk commented

i moved the preprocesses listings over

davidhernandez’s picture

davidhernandez
Primary language English
Location USA
CreditAttribution: davidhernandez commented
Issue summary: View changes
Sutharsan’s picture

Sutharsan CreditAttribution: Sutharsan commented
Assigned: Unassigned » Sutharsan
Sutharsan’s picture

Sutharsan CreditAttribution: Sutharsan commented
Assigned: Sutharsan » Unassigned

views_preprocess_page removes the 'contextual-region' body class if the page content is a view. This is a very specific case which I think should not be replaced with a removeClass() in the template.

bartik_preprocess_page and seven_preprocess_page pass body classes to the html template. A similar situation is discussed in #2329753: Move html classes from preprocess to templates.

I can not come up with a descent in-template alternative for adding classes to 'main_menu' and 'secondary_menu'.

davidhernandez’s picture

davidhernandez
Primary language English
Location USA
CreditAttribution: davidhernandez commented
Status: Active » Closed (won't fix)

I'm not seeing anything relevant here any more. Most of what we needed was changed in the html issue. preprocess_page isn't adding any classes.

Bartik and Seven are going through their own refactoring, so their changes can be worried about elsewhere. Also, Bartik and Seven changes don't affect core or Classy.