Create select dropdown with themes for PMPro Register Helper

pmpro-register-helper-example-with-select-themes.php

function my_pmprorh_init()
{
    //don't break if Register Helper is not loaded
    if(!function_exists("pmprorh_add_registration_field"))
    {
        return false;
    }
    //define the fields
    $fields = array();
    
    $all_themes = wp_get_themes();
    $theme_options = array();
    
    foreach($all_themes as $key => $value)
    {
	    $theme_options[] = $value->get('Name');
    }

    $fields[] = new PMProRH_Field(
        "theme",                   // input name, will also be used as meta key
        "select",                   // type of field
        array(
            "options"=> $theme_options
        ));
    //add the fields into a new checkout_boxes are of the checkout page
    foreach($fields as $field)
        pmprorh_add_registration_field(
            "checkout_boxes", // location on checkout page
            $field            // PMProRH_Field object
        );
    //that's it. see the PMPro Register Helper readme for more information and examples.
}
add_action("init", "my_pmprorh_init");