gravity forms : use previous dropdown choice as variable in gform_pre_render? [closed]

I have a question regarding gform_pre_render?

I have dealer form. Which basically you choose your county, and then your dealer.

Dropdown A = Dealer Country
Dropdown B = Dealer Name

I have about 15 countries, and I am using get_terms in the gform_pre_render function to list all my countries that I have assigned to a dealer post…

// Dropdown A - Dealer Country
add_filter("gform_pre_render", "dropdown_dealer_country");
add_filter("gform_admin_pre_render", "dropdown_dealer_country");
function dropdown_dealer_country($form){

    if($form["id"] != 3)
       return $form;

    $terms = get_terms("dealer-country");

    $items = array();
    $items[] = array( "text" => __('Select country...','mission-theme'), "value" => 0 );

    foreach($terms as $term)
        $items[] = array( "text" => $term->name, "value" => $term->slug );

    foreach($form["fields"] as &$field)
        if($field["id"] == 6){
            $field["choices"] = $items;
        }

    return $form;
}

OK so the above function works perfectly in Dropdown A.

Now what I am trying to do in Dropdown B is display all my dealer names.

I have named each dealer custom post-type title with the name of the dealer, and this is what I am pre populating my secondary drop down with…

// Dropdown B - Dealer Name
add_filter("gform_pre_render", "dropdown_dealer_name");
add_filter("gform_admin_pre_render", "dropdown_dealer_name");
function dropdown_dealer_name($form){

    if($form["id"] != 3)
       return $form;

    $dealers = get_posts(array(
        "post_type" => "dealer",
        "dealer-country" => $dealerCounty,
        "post_status" => "publish",
        "orderby" => "title",
        "order" => "ASC",
        "posts_per_page"  => -1
    ));

    $items = array();
    $items[] = array( "text" => __('Select dealer...','mission-theme'), "value" => 0 );

    foreach($dealers as $dealer)
        $items[] = array( "text" => $dealer->post_title, "value" => $dealer->post_name );

    foreach($form["fields"] as &$field)
        if($field["id"] == 7){
            $field["choices"] = $items;
        }

    return $form;
}

…and as you can see in line 11, I have a variable in my get_posts array “dealer-country” => $dealerCounty

My question, is it some how posible to get the choice that is made in Dropdown A into my $dealerCounty variable in my Dropdown B function?

Any tips or help would be much appreciated as my Dropdown B is currently very long, and I need to filter it down by country.

If any one knows a method that would be great. Thanks in advance.

Eventually the solution I used was this. Upon change of Dropdown A I have an ajax function request tha re-populated Downdown B with the filtered options based on the selection in Dropdown A.

See the ajax jquery script…

countryFilter = function () {

    var countryClass=".dealer-country select",
        dealerClass=".dealer-name select";

    $(countryClass).change(function(){

        var countrySelect = $(this),
            country = countrySelect.val(),
            dealerSelect = countrySelect.parents('form').find(dealerClass);

        if(country != "default") {

            $.ajax({
                type: 'POST',
                url: '<?php echo admin_url('admin-ajax.php'); ?>',
                data: { dealerCountry : country, action: 'get_dealer_name' },
                success: function(data){
                    dealerSelect.empty();
                    var options = $.parseJSON(data);
                    for(i=0;i<options.length;i++){
                        dealerSelect.append('<option value="'+options[i].value+'">'+options[i].text+'</option>');
                    }
                    dealerSelect.removeAttr('disabled');
                }
            });

        }

    });

}

Which I fired using…

$(document).ready(function () { 

    countryFilter();

});

$(document).bind('gform_post_render', function(event, form_id){

    if(form_id == 3) {

        countryFilter();

    }

});

I then trimed my original functions to…

    // Dropdown A - Dealer Country
add_filter("gform_pre_render", "dropdown_dealer_country");
add_filter("gform_admin_pre_render", "dropdown_dealer_country");
function dropdown_dealer_country($form){
        if($form["id"] != 3)
           return $form;
        $terms = get_terms("dealer-country");
        $items = array();
        $items[] = array( "text" => __('Select country...','theme'), "value" => 'default' );
        foreach($terms as $term)
            $items[] = array( "text" => $term->name, "value" => $term->slug );
        foreach($form["fields"] as &$field){
            if($field["id"] == 6 ){
                $field["cssClass"] = 'dealer-country';
                $field["choices"] = $items;
            }  
        }
        return $form;  
    }

    // Dropdown B - Dealer Name
add_filter("gform_pre_render", "dropdown_dealer_name");
add_filter("gform_admin_pre_render", "dropdown_dealer_name");
function dropdown_dealer_name($form){
        if($form["id"] != 3)
           return $form;
        $items = array();
        $items[] = array( "text" => __('Select dealer...','theme'), "value" => 'default' );
        foreach($form["fields"] as &$field){
            if($field["id"] == 7){
                $field["cssClass"] = 'dealer-name';
                $field["choices"] = $items;
            }
        }
        return $form; 
    }

Then the finishing touch is the function which also goes in the functions.php – this is called by the ajax request…

function get_dealer_name_fn(){
    $dealerCountry = $_POST['dealerCountry'];
    $dealers = get_posts(array(
        "post_type" => "dealer",
        "dealer-country" => $dealerCountry,
        "post_status" => "publish",
        "orderby" => "title",
        "order" => "ASC",
        "posts_per_page"  => -1
    ));
    $items = array();
    $items[] = array( "text" => __('Select dealer...','theme'), "value" => 'default' );
    foreach($dealers as $dealer){
        $items[] = array( "text" => $dealer->post_title, "value" => $dealer->post_title );
    }
    echo json_encode($items);
    die;
}
add_action('wp_ajax_get_dealer_name', 'get_dealer_name_fn');
add_action('wp_ajax_nopriv_get_dealer_name', 'get_dealer_name_fn');