ACF: Display custom metabox on an ACF (sub-) options page

acf-custom-metabox-on-options-page.php

<?php

/**
 * Add sub options page with a custom post id
 */
if( function_exists('acf_add_options_page') ) {
	acf_add_options_sub_page(array(
		'page_title' 	=> 'CSV Sync',
		'menu_title' 	=> 'CSV Sync',
		'parent_slug' 	=> 'users.php',
		'post_id'       => 'aa_ucs',
		'autoload'      => false,
	));
}

/**
 * Registers a metabox with ACF for a particular screen. You may need to find the screen ID yourself.
 */
function aa_ucs_register_acf_metabox() {
	// Verify the screen ID
	if ( !acf_is_screen( 'users_page_acf-options-csv-sync' ) ) return;
	
	// Add meta box
	add_meta_box( 'meta-box-id', __( 'My Meta Box', 'textdomain' ), 'aa_ucs_display_acf_metabox', 'acf_options_page', 'normal' );
}
add_action( 'acf/input/admin_head', 'aa_ucs_register_acf_metabox', 10 );

/**
 * Display custom metabox on an ACF options page
 */
function aa_ucs_display_acf_metabox() {
	$text = get_option( 'example-text' );
	?>
	<input type="text" name="exampletext" placeholder="Enter some example text to be saved" value="<?php echo esc_attr($text); ?>">
	<?php
}

/**
 * Submit metabox form, save the results
 * 
 * @param $post_id
 */
function aa_ucs_save_acf_metabox_fields( $post_id ) {
	if ( $post_id != 'aa_ucs' ) return;
	
	$text = isset($_POST['exampletext']) ? stripslashes($_POST['exampletext']) : false;
	
	update_option( 'example-text', $text );
}
add_action( 'acf/save_post', 'aa_ucs_save_acf_metabox_fields', 20 );

Thanks for this. I spent at least an hour trying to put together the right Google search and finally ended up here which is exactly what I needed.

I'm glad it helped you out! I had the same trouble finding a solution and pieced this together based on how the ACF source code creates meta boxes. As far as I know this is the best "ACF way" to do this. Let me know if you have any suggestions for it :)

What can I say less than PERFECT.
Thank you so much for saving our times in (THE RIGHT WAY).

One of the thing I hate in any paid extensions that the creators or what ever we can name them mean to make you get lost when you need to do the thing in the right way.

I saw your comment in ACF blog too, and the wear thing that they never reply to you in the same time they replied to my email in something else also with the wrong answer.

Thank you so much @RadGH.

@etomProductions Thanks, I really appreciate that! I'm glad you found this helpful 🙂

Thanks for this example @RadGH!

For anyone else who may be stuck with acf/save_post not firing, you need at least 1 real ACF field attached to the options page.