Dynamically populate price field dropodown

oh and another thing... since it's a dropdown AND a price field, I guess each option in the select item should have a label and a value (price); I would like to get both of these values from custom fields.

I tried following the instructions above but my code below doesn't seem to work

add_filter('gform_pre_render_7', 'populate_prices');
function populate_prices($form){
    foreach($form['fields'] as &$field){
        if($field['type'] != 'select' || strpos($field['cssClass'], 'populate-prices') === false)
            continue;
        $post = $wp_query->post;
        if(get_field('package_paxbase', $post->ID)) {
            $pax = array();
            while(the_repeater_field('package_paxbase', $post->ID)) {
                $pax[0] = get_sub_field('package_1_base');
                $pax2to3 = get_sub_field('package_2_3_base');
                $pax[1] = 2 * $pax2to3;
                $pax[2] = 3 * $pax2to3;
                $pax4to6 = get_sub_field('package_4_6_base');
                $pax[3] = 4 * $pax4to6;
                $pax[4] = 5 * $pax4to6;
                $pax[5] = 6 * $pax4to6;
                $pax7to9 = get_sub_field('package_7_9_base');
                $pax[6] = 7 * $pax7to9;
                $pax[7] = 8 * $pax7to9;
                $pax[8] = 9 * $pax7to9;
                $pax10to14 = get_sub_field('package_10_14_base');
                $pax[9] = 10 * $pax10to14;
                $pax[10] = 11 * $pax10to14;
                $pax[11] = 12 * $pax10to14;
                $pax[12] = 13 * $pax10to14;
                $pax[13] = 14 * $pax10to14;
                $pax15to19 = get_sub_field('package_15_19_base');
                $pax[14] = 15 * $pax15to19;
                $pax[15] = 16 * $pax15to19;
                $pax[16] = 17 * $pax15to19;
                $pax[17] = 18 * $pax15to19;
                $pax[18] = 19 * $pax15to19;
                $pax20to24 = get_sub_field('package_20_24_base');
                $pax[19] = 20 * $pax20to24;
                $pax[20] = 21 * $pax20to24;
                $pax[21] = 22 * $pax20to24;
                $pax[22] = 23 * $pax20to24;
                $pax[23] = 24 * $pax20to24;
                $pax25to29 = get_sub_field('package_25_29_base');
                $pax[24] = 25 * $pax25to29;
                $pax[25] = 26 * $pax25to29;
                $pax[26] = 27 * $pax25to29;
                $pax[27] = 28 * $pax25to29;
                $pax[28] = 29 * $pax25to29;
                $pax30to34 = get_sub_field('package_30_34_base');
                $pax[29] = 30 * $pax30to34;
                $pax[30] = 31 * $pax30to34;
                $pax[31] = 32 * $pax30to34;
                $pax[32] = 33 * $pax30to34;
                $pax[33] = 34 * $pax30to34;
            }
        }
        $choices = array(array('text' => __('Numero persone', 'salgari'), 'value' => ' '));
        $i = 1;
        foreach($pax as $price) :
            $count = $i++;
            $choices[] = array('text' => $count, 'value' => $price, 'price' => $price);
        endforeach;
        $field['choices'] = $choices;
    }
    return $form;
}

never mind about the simple price field, I managed to do that

now I'm trying to dynamically populate price options checkboxes

which method is required for those? same as dropdown with $choices ?

line 8 of the first pastie containing only the snippet for the checkboxes, there were missing quotes for "label", I fixed it but no change

I found out if remove the brackes [] from $checkboxes[] (line 7) and $inputs[] (line 8) the code will work, but of course the foreach won't and the array will be filled only with the last array key I'm feeding the loop

I'm looking for a solution, probably something wrong with my code

Dweanus in my case it's about price fields; the method suggested in that documentation page is not suitable for price fields, I had to specific the ID of the price field I wanted to modify, both for dropdowns and checkboxes

Anyway, the dropdown issue is fixed... if there had been a way to contribute to the documentation pages I wouldn't mind having helped in this case

Now I have still one issue open about the checkboxes (check a couple of my posts above http://www.gravityhelp.com/forums/topic/dynamically-populate-price-field-dropodown#post-49969 ) - if the mods wish me to open a new thread for that it's fine

I agree documentation should be commented - I follow WooCodex for WooCommerce and it has that feature, I like it

cheers