Get value form previous page (Gravity form)

get-data-from-previous-page-gravity-form.php

<?php
// In this example im going to get certain fields that the user put in in the first page 
// then make them choices on the second page
// You can paste this in your child's functions.php
add_filter('gform_pre_render_1', 'select_username_callback'); //only get data form form id 1
function select_username_callback($form) {
      // To get what page you are on
      $current_page = GFFormDisplay::get_current_page($form["id"]);
      if ($current_page == 2) {
            // Get values from previous form
            $value1 = rgpost( 'input_5' );
            $value2 = rgpost( 'input_24' );
            $value3 = rgpost( 'input_23' );

            // Get fields from current form
            foreach($form["fields"] as &$field) {
                  // Get the specific field through its field id
                  if ($field["id"] == 27) { // Field number 27 is a radio button 
                        // Store values got form previous page in an array
                        $choices = array(
                              array( 'text' => $value1, 'value' => $value1 ),
                              array( 'text' => $value2, 'value' => $value2 ),
                              array( 'text' => $value3, 'value' => $value3 )
                        );
                        /
                        // Store values in the raddio field
                        $field->choices = $choices;
                        $field->placeholder = 'Select a Display Name';
                  }
            }
      }
      return $form;
}