Activate Child Theme with Codex

Question

I know there is an option to have the following code in the wp-config.php file:

define('WP_DEFAULT_THEME', 'x-child-integrity-light');
define( 'TEMPLATEPATH', 'wp-content/themes/x');

I currently have this commented out and I'm trying to use the WP Replicator to replicate sites in a multisite install. I'd like to have the code automatically activate the child theme when it's installing the new site. By default, it's making the Twenty Fifteen theme active. How can I go about doing this?

Answer 1

Use switch_theme as already indicated in another answer, but hook it to wpmu_new_blog

This function runs when a user self-registers a new site as well as when a super admin creates a new site. hook to 'wpmu_new_blog' for events that should affect all new sites.

https://codex.wordpress.org/function_reference/wpmu_create_blog

If not the code will run constantly, which will be inefficient and make switching themes impossible ( or unpredictable ).

In other words:

function default_theme_wpse_193024() {
  switch_theme('twentythirteen');
}
add_action('wpmu_new_blog','default_theme_wpse_193024');

For switch_theme(), despite the parameter being named somewhat inexplicably "stylesheet", use the name of the theme folder. Per the Codex:

Accepts one argument: $stylesheet of the theme. ($stylesheet is the name of your folder slug. It's the same value that you'd use for a child theme, something like twentythirteen.)

Answer 2

You can use the switch_theme function

<?php switch_theme( $stylesheet ) ?>

$stylesheet is the Stylesheet name.