WordPress replace header.php from a plugin - wordpress

Question

I have searched and cant find any answer.
How can I replace the themes header.php template from a custom plugin?
Everywhere I look it seems like it cant be done, and you can only change template parts from a theme/child theme.
But how does plugins like Elementor page builder do it then in their theme builder?
Thanks,
Daniel

Answer 1

I also needed to include a custom header.php from my plugin. Because you can register templates like page.php, post.php or archive.php from a plugin via the ${type}_template hook, I thought it shouldn't be that difficult to do the same for the header.php, but you can't load a custom header.php from directories other than parent or child theme's one.
When traversing down the get_header function you'll see the locate_template function being invoked to load the header template. But there is no way to hook into that function and to replace the path for the loaded header template:
function locate_template( $template_names, $load = false, $require_once = true, $args = array() ) {
$located = '';
foreach ( (array) $template_names as $template_name ) {
if ( ! $template_name ) {
continue;
}
if ( file_exists( STYLESHEETPATH . '/' . $template_name ) ) {
$located = STYLESHEETPATH . '/' . $template_name;
break;
} elseif ( file_exists( TEMPLATEPATH . '/' . $template_name ) ) {
$located = TEMPLATEPATH . '/' . $template_name;
break;
} elseif ( file_exists( ABSPATH . WPINC . '/theme-compat/' . $template_name ) ) {
$located = ABSPATH . WPINC . '/theme-compat/' . $template_name;
break;
}
}
if ( $load && '' !== $located ) {
load_template( $located, $require_once, $args );
}
return $located;
}
One solution to bypass this limitation would be to get rid of the get_header function within your plugin's templates and to include the plugin's header.php via require or require_once statement from within the plugin's templates. But than you will have to implement your own get_header hook and locate_template functionality to enable replacement from the parent or child theme. See this answer for more information on limitations when omitting the get_header function:
https://wordpress.stackexchange.com/a/5195/80177

Answer 2

I have experience using a similar page-builder to elementor called site origin.
To the best of my knowledge wordpress page-builders don't manipulate or replace the themes template files. Instead, a lot of the page-builder content is displayed in the front end with the_content() found in your template file. In addition, it appends a bunch of css and js scripts to the web page in order to handle the styling of the elements and interactivity.
As for your original question... If I understand correctly, there's no need for this plugin because the header.php file can be freely edited/replaced in the theme editor!
In the admin section, go to 'appearance' > 'editor'. Then under "theme files", select the template for header.php.

Answer 3

I used this solution
add_action('get_header', 'wpbet_replace_theme_header');
function wpbet_replace_theme_header(){
require plugin_dir_path( __FILE__ ) . 'templates/headers/header-padrao.php';
$templates = [];
$templates[] = 'header.php';
remove_all_actions( 'wp_head' );
ob_start();
locate_template( $templates, true );
ob_get_clean();
}

Answer 4

Elementor does not replace the header.php. It adopts whatever header.php the active theme has. It simply takes over the_content() part.
header.php is essential part & asset of a theme.
You may build a page template with a different header (not different header.php)