Sage 9 child theme

sage
8

I’m trying use Sage 9 for a child theme. Not sure this is best practice, but it worked for me:

In functions.php:

add_filter('template', function ($stylesheet) {
  $this_theme = wp_get_theme();
  return $this_theme['Template'];
});

if (basename($stylesheet = get_option('template')) !== 'templates') {
  $theme_dir = get_option('stylesheet');
  update_option('template', "{$theme_dir}/templates");
  wp_redirect($_SERVER['REQUEST_URI']);
  exit();
}
4 Likes
9

Any thoughts on this for Sage 9? I’ve tried to implement a parent/child theme, but am getting a broken theme error message on child themes saying it cannot find the parent.

10

@timothy_m_alber I’ve managed to change the functions.php file to get child themes working, which version of Sage 9 are you running so that I can help out?

You can find this out by checking out the CHANGELOG.MD file in the root of the theme

2 Likes
11

thanks @craigpearson – I am using beta 3. Very interested to know how you were able to get this working!

1 Like
12

Sorry about the delay, I’m looking into this now.

I had thought I’d got a solution to this but there’s an issue which I didn’t pick up on previously. And that is the template hierarchy doesn’t get overridden due to the way blade is working. i.e. creating an index.blade.php file in the child theme won’t actually override it’s equivalent in the parent - I’m not sure how I missed such a big issue.

Weirdly this behaviour is only present in beta 3 and seems to work in beta 2. I’m going to stick at this for a couple of hours and post my findings

13

So I don’t think this is possible with Sage 9 Beta 3.

Moving styles.css to /resources in beta 3 has had an adverse affect on the effectiveness of the WordPress function locate_template which is also used by get_template_part.

You can see that function here: https://developer.wordpress.org/reference/functions/locate_template/#source

On a singular theme level moving the style.css doesn’t really have any downsides as Sage 9 Beta 3 also has stylesheet filters in place in functions.php - when the stylesheet entry doesn’t find a template file it defaults to the template entry. All is good in the world.

However, on a child theme level the locate_template function ceases to work as expected due to the constant STYLESHEETPATH. This constant expects wordpress templating files to be in the same directory as itself for child themes to work and override templates as we’re used to. This is why get_stylesheet_directory_uri and get_template_directory_uri yield different results when used in child themes.

In a child theme when STYLESHEETPATH is filtered/changed it causes the theme to deactivate or miss template overwrites. This is because at child level the stylesheet location is used both for activation, and theme file location. When in a child and parent scenario the stylesheet entry must be the child theme’s stylesheet location, and the template entry must be the parent theme. To my knowledge it’s not possible to have your pie and eat it because of this.

The only solutions I can see for this issue are:

  • Manually require_once the parent functions file after load and drop WordPress default parent / child relationship - Most plugins, frameworks (WooCommerce etc) and themes depend on this ordering quite religiously so I don’t see this as feasible
  • Move styles.css and functions.php back to the root of the theme like in beta 2 and adjust the template directory filter when it is a child
  • Move styles.css and functions.php into the views folder or a templates folder to make finding a solution easier
  • Request a patch in WordPress core for the loading order of these files (Stupid to event think that’d be accepted)
  • Do some trickery with Laravel / Blade - a wrapper for locate template perhaps

Of course I could be completely wrong and the roots team may already have their eye on a fix

2 Likes
14

Thanks for the investigation @craigpearson! I hope the Roots team will have a solution for child theme compatibility!

15

How’d you get it working in beta 2? I’m happy to use beta 2 instead of 3.

16

Hey @Luke_Abell,

I’ll try and get this up for the weekend - my themes have quite a few customizations on top of sage so I need to clear out the unnecessary before sharing :thumbsup:

17

Thanks! Any luck getting this set up?

18

@Luke_Abell Really sorry about the delay with this I’m mid project and the heat is on. As a rough guide:

  • Grab the roots theme at this point before the directory change. Then cherry pick any other changes which have been merged to roots thereafter. You can cherry pick those improvements from the commit history but be sure to understand that this may well be a hands on manual process.

  • Duplicate that project as a child theme. Being sure the appropriate Template: parent-theme-folder is in your chld theme style.css in the top comments. And that your theme name is unique.

  • In the parent theme’s function file replace this block with the following:

/**
 * Sage required files
 *
 * The mapped array determines the code library included in your theme.
 * Add or remove files to the array as needed. Supports child theme overrides.
 */
array_map(function ( $file ) use ( $sage_error ) {
	if ( is_child_theme() ) {
		$file = "../src/{$file}.php";
	} else {
		$file = "src/{$file}.php";
	}

	if ( ! locate_template( $file, true, true ) ) {
		$sage_error(sprintf( __( 'Error locating <code>%s</code> for inclusion.', 'sage' ), $file ), 'File not found');
	}
}, [ 'helpers', 'setup', 'filters', 'admin' ]);
  • In the child theme functions file replace this block with the one below:
/**
 * Here's what's happening with these hooks:
 * 1. WordPress initially detects theme in themes/sage
 * 2. Upon activation, we tell WordPress that the theme is actually in themes/sage/templates
 * 3. When we call get_template_directory() or get_template_directory_uri(), we point it back to themes/sage
 *
 * We do this so that the Template Hierarchy will look in themes/sage/templates for core WordPress themes
 * But functions.php, style.css, and index.php are all still located in themes/sage
 *
 * This is not compatible with the WordPress Customizer theme preview prior to theme activation
 *
 * get_template_directory()   -> /srv/www/example.com/current/web/app/themes/sage
 * get_stylesheet_directory() -> /srv/www/example.com/current/web/app/themes/sage
 * locate_template()
 * ├── STYLESHEETPATH         -> /srv/www/example.com/current/web/app/themes/sage
 * └── TEMPLATEPATH           -> /srv/www/example.com/current/web/app/themes/sage/templates
 */
if ( is_customize_preview() && isset( $_GET['theme'] ) ) {
	$sage_error(__( 'Theme must be activated prior to using the customizer.', 'sage' ));
}

if ( basename( $stylesheet = get_option( 'template' ) ) !== 'templates' ) {
	update_option( 'template', "{$stylesheet}/templates" );
	wp_redirect( $_SERVER['REQUEST_URI'] );
	exit();
}

Finally in your child theme remove the includes which only need to be part of the parent, so for example change this block to this:

array_map(function ( $file ) use ( $sage_error ) {
	$file = "src/{$file}.php";

	if ( ! locate_template( $file, true, true ) ) {

		// $sage_error(sprintf( __( 'Error locating <code>%s</code> for inclusion.', 'sage' ), $file ), 'File not found');
	}
}, [ 'setup' ]);
  • Finally, and this is the hackiest part, manually include your parents functions file. By adding this line to very bottom of your childs functions.php file like so. Be sure to change both parent-theme-folder lines
require_once( get_theme_root( 'parent-theme-folder-name' ) . '/parent-theme-folder-name/functions.php' );

Now the reason there’s a delay in me getting this to you is that this isn’t the most elequent way, and I have got a more pragmatic solution as opposed to a manual include of the parent functions file. However that code is wrongly entwined with some other must use plugins. I’ll update this thread as soon as I can with that solution, hopefully in ~2 weeks

NB in your setup file in your child you may also want to include your parent css file, or alternatively alter your main.scss file to import your parents main.scss file depending on how you want your CSS/JS relationship to work

2 Likes
19

Thanks @craigpearson – have you looked into their new child theme support in beta 4?

20

Yep, I’d recommend updating, it works like a dream!

There’s still some modifications to make on getting JS and SASS inheriting from the parent (if needed) but definitely a lot more reliable than my hacky solution!

21

Hey @craigpearson! Can you point me in the right direction for the beta 4 child theme modifications? I’m having trouble finding any official documentation and I’d really like to use child themes across a multisite I’m starting development on. Thanks!

22

Sure, here’s my process

Set the child theme’s parent

Add the correct template name by appending /resources to the parent theme folder:

// child-theme/resources/style.css
/*
Theme Name:         Sage Starter Theme
... etc

Template:           parent-theme/resources
*/

Remove conflicts / duplicates
You need to remove functions in the child which are already inherited from the parent theme

// Remove duplicate files
child-theme/app/admin.php
child-theme/app/filters.php
child-theme/app/setup.php

Start fresh (optional)
I’d recommend removing all template files in the child theme, overwriting them as needed

// Remove view files, overwrite later
child-theme/resources/views/*

From here we can use child template overwrites as we normally would

Import parent styles (optional)
Using your parent theme styles as a base can be helpful and more maintainable

// child-theme/resources/assets/styles/main.scss
@import "/../../../../parent-theme/resources/assets/styles/main";

Note There are issues when using @import '/autoload/**/*'; within the parent theme - manually including assets is your friend again here.

Import parent JS (optional)
Remove all contents of main.js in the child theme, and import the parent

// child-theme/resources/assets/scripts/main.js
import '../../../../parent-theme/resources/assets/scripts/main.js';

You need to run yarn and composer install within both themes. Your build process is done the same ol way as you always have per theme

Oh, and
This doesn’t account for any node modules, images or other assets between themes. If you do roll with the import options above, you’ll need to decide on whether to duplicate those or go a little further with customisation

11 Likes
23

@craigpearson you are MVP. Thanks for responding so fast, and with so much detail! :hugs:

1 Like
24

Thanks for the continued updating on this post.
I’m attempting to import parent JS as indicated here but am getting the error:

This relative module was not found:

./autoload/**/* in ../my-parent-theme/resources/assets/scripts/main.js

Do you have any guidance on this?

25

Note There are issues when using @import '/autoload/**/*'; within the parent theme - manually including assets is your friend again here.

When using wildcards to autoload in a child theme - from the parent, there’s issues.

For our projects we don’t need this autoload behaviour so to keep this functionality might need further customisation.

To resolve your issue (at a loss of auto imports) just include your autoloaded scss/JS files in your parent theme manually. For example, in scss:

@import '/autoload/bootstrap.scss';

I wish I could verbalise more succinctly why this is the case, but in all honesty I’ve had a couple of wines because of that Santa guy

1 Like
26

I’m struggling to get a child theme going with the latest release – has anyone been able to get things running?

Thanks @craigpearson for the pointers so far, should it be a matter of updating the paths you’ve provided in your instructions above?

Is the idea to follow both of your posts? This Sage 9 child theme and then this Sage 9 child theme?

27

Hey @canarystudio,

Sorry for the confusion but the steps to follow would be these steps alone: Sage 9 child theme

Following steps previous that post are no longer relevant.

Just to confirm the approach mentioned in there still works with the stable release of Sage V 9.0.0

If you’re getting any specific errors / issues feel free to share and hopefully I can offer some advice

1 Like