1.
Working with Child Themes
Utsav singh @rathour
Blogs at: http://codepixelz.com
(@codepixelzmedia)
Dev @ Jasper IT Solutions

2.
Because we should.
Why way to theme
bother?
Better
Automattic recommends.
Next developer will thank you.

3.
Bother to Explain?
Of course Not
That is why I am here.

4.
A quick survey:
Who among here...
• Understands what a child theme is?
• has created and used child themes?

5.
Scenario #1

6.
Scenario #2
Let me make some crazy changes to the
theme code.
Oh wow! An Update. *clickity click*

7.
Been there before?
How does it feel?

8.
Enter: Child Theme
• Inherits the functionality of parent theme
• Allows you to:
- Modify Parent theme
- Add Features to the Parent theme
• Safest and easiest way to modify

9.
Like Father Like Son

10.
Like Father Like Son
Is just like the parent.
A little modification here and there
A little features added here and there

11.
Changes are lost while updating, parent theme
Why use Child Theme?
Speeds up Development Process
Overrides the parts of parent theme that you specify,
without actually changing the theme itself.

12.
Great another week or two of
learning 
Nope, this is easier than most of you have
thought it would be.
This is moreover like any other theme.

13.
How to create a Child Theme?

14.
How to create a Child Theme?

15.
How to create a Child Theme?
Create style.css inside the folder and add this
/*
Theme Name: Twenty Thirteen Child Theme
URI: http://codepixelz.com/twenty-thirteen-child/
Description: Twenty Thirteen Child Theme
Author: Utsav Singh Rathour
Author URI: http://codepixelz.com
Template: twentythirteen
Version: 1.0.0
*/

16.
How to create a Child Theme?

17.
How to create a Child Theme?
Why this Kolaveri D?
@import url("../twentythirteen/style.css");

18.
Go Ahead, make CSS changes that you wanted
What next?
to make.
Customize

19.
But I have more than just CSS to
change

20.
Working with Templates
Simply create a file with same name and it
overwrites same file from Parent theme
Eg: header.php in child replaces parent’s header.php

21.
Working with Templates
• Parent’s header.php
wp_nav_menu( array( 'theme_location' => 'primary', 'menu_class' => 'nav-menu' ) );
get_search_form();
• Child’s header.php
wp_nav_menu( array( 'theme_location' => 'primary', 'menu_class' => 'nav-menu' ) );
//get_search_form();

22.
Including a File
• require_once( get_stylesheet_directory() . '/my_included_file.php' );
why get_stylesheet_directory()?
Because get_template_directory() returns Parent themes path.
• get_template_part( 'content', get_post_format() );
Note:
It looks for say, content-video.php on child theme, if not found; before falling back
to content.php on child. Searches for the file in parent.

23.
Handling Functions
• Child’s, functions.php is loaded before
Parent’s functions.php
• you can make the user functions replaceable
by a child theme, by declaring them
conditionally

24.
Handling Functions
Make sure your parent theme has functions defined
this way.
if ( ! function_exists( 'theme_special_nav' ) ) {
function theme_special_nav() {
// Do something.
}
}

25.
But wait…
• Just because you can, doesn’t mean you should.
• Be wise: “Measure Twice, Cut Once”
• Almost anyone can become a parent, but not all are good
parents. And same applies for themes.

26.
Good Parent and Bad Parent
• Good Parent's functions look like:
if ( ! function_exists( 'do_this' ) ) {
//Something here
}
• Bad Parent's functions look like :
function do_this(){
// Something here
}

27.
When not to use Child theme?
• When you are creating a theme and know, you won’t
update
• Using a theme that never updates.
• Because it is confusing to client.
• Because it is a little slow.

28.
Go Ahead! Experiment!
Find more at: http://codex.wordpress.org/Child_Themes

29.
Questions?