Description: Customize the GF progress bar by removing it from the first page

gf-progress-bar-customization.php

<?php
/**
 * GF Progress Bar Customization
 *
 * @package gf-progress-bar-customization
 * @author  Bernhard Kau
 * @license GPLv3
 *
 * @wordpress-plugin
 * Plugin Name: GF Progress Bar Customization
 * Plugin URI: https://gist.github.com/2ndkauboy/bfa3b0b7623c27548dace6581215dd04
 * Description: Customize the GF progress bar by removing it from the first page
 * Version: 1.0.0
 * Author: Bernhard Kau
 * Author URI: https://kau-boys.de
 * Text Domain: gf-progress-bar-customization
 * License: GPLv3
 * License URI: http://www.gnu.org/licenses/gpl-3.0.txt
 */

/**
 * Check if form is the one we want to customize.
 *
 * @param object $form The form.
 *
 * @retun boolean
 */
function gf_pbc_is_customized_form( $form ) {
	if ( 'processbar-customized' === $form['cssClass'] ) {
		return true;
	}

	return false;
}

/**
 * Check if form progress bar starts at zero.
 *
 * @param boolean $start_at_zero Value for start.
 * @param object  $form          The form.
 *
 * @retun object
 */
function gf_pbc_start_at_zero( $start_at_zero, $form ) {
	return gf_pbc_is_customized_form( $form );
}

add_filter( 'gform_progressbar_start_at_zero', 'gf_pbc_start_at_zero', 10, 2 );

/**
 * Check if form progress bar starts at zero.
 *
 * @param string $progress_bar         The progress bar.
 * @param object $form                 The form.
 * @param string $confirmation_message The conformation message.
 *
 * @retun string
 */
function gf_pbc_change_progressbar_steps( $progress_bar, $form, $confirmation_message ) {
	if ( ! gf_pbc_is_customized_form( $form ) ) {
		return $progress_bar;
	}

	$current_page = GFFormDisplay::get_current_page( $form['id'] );
	$max_page     = GFFormDisplay::get_max_page_number( $form );

	if ( 1 === $current_page ) {
		$progress_bar = '';
	} else {
		$progress_bar = preg_replace_callback(
			'#<p class="gf_progressbar_title">.*(gf_step_current_page?)(?s).*</p>#',
			function ( $matches ) use ( $current_page, $max_page ) {
				if ( ! isset( $matches[1] ) ) {
					return $matches[0];
				}

				return '<p class="gf_progressbar_title">' . sprintf(
					// translators: %1$d: number of page, %2$d: number of max_pages.
						__( 'Question %1$d of %2$d', 'gf-progress-bar-customization' ),
						$current_page - 1,
						$max_page - 1
					) . '</p>';
			},
			$progress_bar
		);
	}

	return $progress_bar;
}

add_filter( 'gform_progress_bar', 'gf_pbc_change_progressbar_steps', 10, 3 );