狠狠撸

The
Child Theme Dilemma
WordCamp Cologne 2015
Torsten Landsiedel

Hello!
Torsten Landsiedel
WordPress- Freelancer
Moderator German Supportforum
Editor Team de.w.org
Translation Contributor and Editor
Co-Organisator WP Meetup Hamburg
Co-Organisator WordCamp Hamburg
@zodiac1978

Child Theme Usage
Who has used Child Themes?

Child Theme Problems
Security
Extensibility
Performance

Security Problems
Parent Theme
search.php (with
vulnerability)
Child Theme
search.php (with
vulnerability)
Parent Theme
search.php (without
vulnerability)
Child Theme
search.php (with
vulnerability)
update
overwrites
no update!overwrites

Child Themes aren’t safe?
Why nobody told us?

Extensibility
Pluggable Functions:
if ( ! function_exists( 'theme_special_nav' ) ) {
function theme_special_nav() {
// Do something.
}
}
Attention:
Now you have to maintain the code!

Missing extensibilities
Framework Theme + Premium Child Theme?
WordPress.org Theme + Child Theme?
Where to put the customizations?
Thre are no Grandchild Themes :(

Why shouldn’t there be Grandchild Themes?

This idea of releasing advanced child themes just creates
the same problem child themes were meant to solve:
upgradability.
– Justin Tadlock
http://justintadlock.com/archives/2010/08/16/frameworks-parent-child-
and-grandchild-themes

Update of Parent Theme
Without any problems?
It depends …
filter/actions removed?
CSS classes changed?
Markup changed?
Paths changed?

Performance Problems
Many Child Themes are using @import
@import url(/slideshow/the-child-theme-dilemma-en/parent-theme/style.css);
But @import stops parallel loading
in all browsers.
http://www.stevesouders.com/blog/2009/04/09/dont-use-import/

Solution:
De-register styles und re-register/re-enqeue parent and
child styles
function twentytwelve_child_scripts() {
wp_deregister_style( 'twentytwelve-style' );
wp_register_style( 'twentytwelve-style',
get_template_directory_uri() . '/style.css' );
wp_enqueue_style( 'twentytwelve-child-style',
get_stylesheet_uri(), array( 'twentytwelve-style' ) );
}
add_action( 'wp_enqueue_scripts', 'twentytwelve_child_scripts', 11 );
Performance problems

Even simpler:
Enqueue parent styles. Done! Just works if
get_stylesheet is used (and just this) in the parent
theme.
// Faster than @import
add_action( 'wp_enqueue_scripts', 'my_child_theme_scripts' );
function my_child_theme_scripts() {
wp_enqueue_style( 'parent-theme-css', get_template_directory_uri() .
'/style.css' );
}

New problem:
Many themes are not build that way.
Hardcoded stylesheets in the header.php for example:
<link rel="stylesheet" type="text/css" media="all"
href="<?php bloginfo( 'stylesheet_url' ); ?>" />

Or the theme is not compatible with using a child
theme.
Or you have to de-register everything to preserve the
correct order.
wp_enqueue_style( 'base_styles',
get_template_directory_uri() . '/css/base.css' );
wp_enqueue_style( 'responsive_styles',
get_template_directory_uri() . '/css/mobile.css' );
wp_enqueue_style( 'ie_styles',
get_template_directory_uri() . '/css/ie.css' );

Can be very complicated for beginners ...

Justin Tadlocks brilliant solution for the parent theme:
function my_enqueue_styles() {
/* If using a child theme, auto-load the parent theme style. */
if ( is_child_theme() ) {
wp_enqueue_style( 'parent-style',
trailingslashit( get_template_directory_uri() ) . 'style.css' );
}
/* Always load active theme's style.css. */
wp_enqueue_style( 'style', get_stylesheet_uri() );
}
add_action( 'wp_enqueue_scripts', 'my_enqueue_styles' );
http://justintadlock.com/archives/2014/11/03/loading-parent-styles-for-child-themes

Hey Torsten!
Grab some water.
Don’t speak too fast.
:)

Security
Extensibilities
Performance ?

Idea 1: Child Theme Lite
“Child themes from theme developers should be nothing
more than a stylesheet and a few functions.”
– Justin Tadlock
http://justintadlock.com/archives/2010/08/16/frameworks-parent-child-and-grandchild-themes

Child Theme just contains functions.php
and style.css.
All changes should just be made with hooks
and filters.
This would be made within a plugin.
Child Theme remains update-ability.

Problem:
How many themes do something like that?

Idea 2: Child Theme Check
Every template file in the theme is ghetting a version
number in the file header.
@version 1.0.0
Check of the version number via plugin
(or even better via WordPress core).
Differences between files can be shown via
wp_text_diff().

Idea 2: Child Theme Check
DEMO!

Child Theme Check
https://github.com/Zodiac1978/tl-template-checker
- This is a Twitter opportunity! -

Security ?
Extensibilities (?)
Performance ?

● Is Tools the right choice for the menu? Or should it be
Appearance?
● Just open an issue on Github:
https://github.com/Zodiac1978/tl-template-checker/issues
Conribute? Great!

Discussion!
Questions? Contradiction? Alternative solutions?
Theme Shop/Theme Developer: Interested?
Let’s speak about it!
@zodiac1978
http://torstenlandsiedel.de/kontakt

Thank you for your time!
Safe travels! :)

狠狠撸

The Child Theme Dilemma (EN)

Recommended

More Related Content

Similar to The Child Theme Dilemma (EN) (20)

More from Torsten Landsiedel (18)

Recently uploaded (20)

The Child Theme Dilemma (EN)