Get the value of a field in gravity forms and use that value as a php parameter?

Question

I am trying to dynamically populate two dropdown fields in a Gravity Forms form. The first field dynamically populates with the terms available in a custom post type. I want the second dynamically populated field to contain the list of all post titles within the custom post type AND have those titles filtered by the term selected in the previous dropdown. Is it possible to get the value of a dropdown within Gravity Forms and pass that value as a parameter in $args to use the get_posts($args) function?

I started using the following tutorial as a guide. https://docs.gravityforms.com/dynamically-populating-drop-down-fields/

add_filter( 'gform_pre_render_3', 'populate_procedures' );
add_filter( 'gform_pre_validation_3', 'populate_procedures' );
add_filter( 'gform_pre_submission_filter_3', 'populate_procedures' );
add_filter( 'gform_admin_pre_render_3', 'populate_procedures' );

function populate_procedures( $form ) {
    // Procedure Category Dropdown
    foreach ( $form['fields'] as &$field ) {

The first field. The following code populates a dropdown field containing a list of all of the terms within a custom post type (procedure):

        if ( $field->type != 'select' || strpos( $field->cssClass, 'populate_procedure_categories' ) === false ) {
            continue;
        }

        $terms = get_terms( array(
            'taxonomy' => 'procedure_category',
            'orderby' => 'name',
            'order'   => 'ASC',
        ) );

        // you can add additional parameters here to alter the posts that are retrieved
        // more info: http://codex.wordpress.org/Template_Tags/get_posts
        //$posts = get_posts( 'post_type=procedure&numberposts=-1&post_status=publish' );

        $choices = array();

        foreach ( $terms as $term ) {
            $choices[] = array( 'text' => $term->name, 'value' => $term->name );
        }

        // update 'Select a Post' to whatever you'd like the instructive option to be
        $field->placeholder = 'Select Procedure Category';
        $field->choices = $choices;

The second field. The following code dynamically populates the field with all of the the post titles of the custom post type (procedure). I want to filter these results based upon the value selected above.

    if ( $field->type != 'select' || strpos( $field->cssClass, 'populate_procedures' ) === false ) {
            continue;
        }

        $args = array(
            'post_status' => 'publish',
            'post_type' => 'procedure',
            'procedure_category' => 'cardiovascular',
        );

        $posts = get_posts( $args );

        $choices = array();

        foreach ( $posts as $post ) {
            $choices[] = array( 'text' => $post->post_title, 'value' => $post->post_title );
        }

        // update 'Select a Post' to whatever you'd like the instructive option to be
        $field->placeholder = 'Select Procedure';
        $field->choices = $choices;
}

    return $form;
}

The second dynamically populated field successfully pulls in the filtered list of post titles based on the $args if I explicitly listed the term (in the example above I used 'cardiovascular'). What I am wondering is if there is a way to grab the value of the previous field and use that to filter the results of the second field (without having to reload the page). Any ideas? Does Gravity Forms have a functionality like this built in?

Answer 1

Using this method, you would need to use multiple pages and add the second Drop Down field to the second page on the form. Then, when the user submits the first page, you can access the value of the first Drop Down from the $_POST. Gravity Forms has a helper method for doing this called rgpost(). Here's what your $args might look like:

$args = array(
    'post_status' => 'publish',
    'post_type' => 'procedure',
    'procedure_category' => rgpost( 'input_FIELDID' ),
);

Replace FIELDID with the field ID of your first Drop Down.

With that said, if you want to accomplish this without having to touch any code, try Gravity Forms Populate Anything.

https://gravitywiz.com/documentation/gravity-forms-populate-anything/