Custom-placeholder-Add-on.php

<?php
/*
Plugin Name: Custom-placeholder Add-on (ACF)
Plugin URI: http://tiptoppress.com/downloads/term-and-category-based-posts-widget/
Description: Add-on to handle custom placeholder like custom fields for the premium widget Term and Category Based Posts Widget.
Author: TipTopPress
Version: 1.1
Author URI: http://tiptoppress.com

Installation:
- Download the file and rename it to Custom-placeholder-Add-on.php
- Upload it to the plugins folder [your-wordpress-installation]/wp-content/plugins/Custom-placeholder-Add-on.php
- Go to WordPress > Admin > PlugIns and activate the Extension
- Now, there is a new sort by: 'Name' visible
*/

namespace termCategoryPostsPro\CustomPlaceholderAddOn;

// Don't call the file directly
if ( !defined( 'ABSPATH' ) ) exit;

/**
 *  Applied to the list of sort orders some new ones.
 *  
 *  @return array of sort orders
 *  
 *  @since 1.1
 */
function custom_field ( $custom_field_names, $that, $instance ) { 
	
	// if values with get_field() or
	// else if taxonomy objects with get_field_object()
	if ( function_exists( 'get_field' ) ) {

		$custom_field_value = get_field( $custom_field_name );

		// uncomment for debug output to /wp-content/debug.log and set define( 'WP_DEBUG, true' ) in your wp-config.php
		// error_log("Filter debug cpwp_custom_placeholder: " . var_dump( $custom_field_name ));

		if ( ! empty( $custom_field_value ) ) {
			
			if ( $custom_field_name == 'my_custom_field' ) {
	
				return	"Title: " . $custom_field_value->name . "</br>";
	
			} else if ( $custom_field_name == 'my_second_custom_field' ) {
	
				return "Office Location: " . $custom_field_value->location . "</br>";
	
			} else if ( $custom_field_name == 'my_array' ) {
	
				$values = "";
				if ( $custom_field_value ) {
					foreach ( $custom_field_value as $value) {
						$values .= '<span>' . $value . '</span>';
					}
				}
				return $values;
			}
		}

	}
}
add_filter( 'cpwp_custom_placeholder', __NAMESPACE__.'\custom_field', 10, 3 );