bp_admin_setting_callback_register_allow_custom_registration()

function bp_admin_setting_callback_register_allow_custom_registration() {

	$allow_custom_registration = bp_allow_custom_registration();
	?>

    <select name="allow-custom-registration" id="allow-custom-registration">
	    <option value="0" <?php selected( 0, $allow_custom_registration ); ?>><?php _e( 'BuddyBoss Registration', 'buddyboss' ); ?></option>
	    <option value="1" <?php selected( 1, $allow_custom_registration ); ?>><?php _e( 'Custom URL', 'buddyboss' ); ?></option>
    </select>
	<?php
    if ( ! $allow_custom_registration ) {
	    printf( '<p class="description">%s</p>',
		    sprintf( __( 'Use the default BuddyBoss registration form. Make sure to configure the <a href="%s">registration pages</a>.',
			    'buddyboss' ),
			    add_query_arg( array(
				    'page' => 'bp-pages'
			    ),
				    admin_url( 'admin.php' ) ) ) );
    }
}