How to create a 'single' category widget for woocommerce plugin [closed]

Question

Woocommerce out of the box provides many widgets, however the category widget for providing a product search, groups ALL the categories into one widget.

I want a widget for one category, i.e. 'shop by meaning' and another widget 'shop by letter' etc.

I grabbed the widget code for widget-product_categories.php from the woocommerce plugin...thinking I could simple modify the code for the 'size' category I created within the woocommerce plugin.

However, I quickly found it's beyond my scope.

Since I need to create 4 different widgets with 'shop by xxx' searches, any help would be appreciated. Below is the code from the woo widget that provides ALL the categories in one widget.

Is there a way to recode this for a single category return for 'size'?

var $woo_widget_cssclass;
var $woo_widget_description;
var $woo_widget_idbase;
var $woo_widget_name;
var $cat_ancestors;
var $current_cat;

/**
 * constructor
 *
 * @access public
 * @return void
 */
function WooCommerce_Widget_Product_Categories() {

    /* Widget variable settings. */
    $this->woo_widget_cssclass = 'widget_product_categories';
    $this->woo_widget_description = __( 'A list or dropdown of product categories.', 'woocommerce' );
    $this->woo_widget_idbase = 'woocommerce_product_categories';
    $this->woo_widget_name = __('WooCommerce Product Categories', 'woocommerce' );

    /* Widget settings. */
    $widget_ops = array( 'classname' => $this->woo_widget_cssclass, 'description' => $this->woo_widget_description );

    /* Create the widget. */
    $this->WP_Widget('product_categories', $this->woo_widget_name, $widget_ops);
}


/**
 * widget function.
 *
 * @see WP_Widget
 * @access public
 * @param array $args
 * @param array $instance
 * @return void
 */
function widget( $args, $instance ) {
    extract( $args );

    $title = apply_filters('widget_title', empty( $instance['title'] ) ? __( 'Product Categories', 'woocommerce' ) : $instance['title'], $instance, $this->id_base);
    $c = $instance['count'] ? '1' : '0';
    $h = $instance['hierarchical'] ? true : false;
    $s = (isset($instance['show_children_only']) && $instance['show_children_only']) ? '1' : '0';
    $d = $instance['dropdown'] ? '1' : '0';
    $o = isset($instance['orderby']) ? $instance['orderby'] : 'order';

    echo $before_widget;
    if ( $title ) echo $before_title . $title . $after_title;

    $cat_args = array('show_count' => $c, 'hierarchical' => $h, 'taxonomy' => 'product_cat');

    if ( $o == 'order' ) {

        $cat_args['menu_order'] = 'asc';

    } else {

        $cat_args['orderby'] = 'title';

    }

    if ( $d ) {

        // Stuck with this until a fix for http://core.trac.wordpress.org/ticket/13258
        woocommerce_product_dropdown_categories( $c, $h, 0 );

        ?>
        <script type='text/javascript'>
        /* <![CDATA[ */
            var dropdown = document.getElementById("dropdown_product_cat");
            function onCatChange() {
                if ( dropdown.options[dropdown.selectedIndex].value !=='' ) {
                    location.href = "<?php echo home_url(); ?>/?product_cat="+dropdown.options[dropdown.selectedIndex].value;
                }
            }
            dropdown.onchange = onCatChange;
        /* ]]> */
        </script>
        <?php

    } else {

        global $wp_query, $post, $woocommerce;

        $this->current_cat = false;
        $this->cat_ancestors = array();

        if ( is_tax('product_cat') ) :

            $this->current_cat = $wp_query->queried_object;
            $this->cat_ancestors = get_ancestors( $this->current_cat->term_id, 'product_cat' );

        elseif ( is_singular('product') ) :

            $product_category = wp_get_post_terms( $post->ID, 'product_cat' );

            if ($product_category) :
                $this->current_cat = end($product_category);
                $this->cat_ancestors = get_ancestors( $this->current_cat->term_id, 'product_cat' );
            endif;

        endif;

        include_once( $woocommerce->plugin_path() . '/classes/walkers/class-product-cat-list-walker.php' );

        $cat_args['walker']             = new WC_Product_Cat_List_Walker;
        $cat_args['title_li']           = '';
        $cat_args['show_children_only'] = ( isset( $instance['show_children_only'] ) && $instance['show_children_only'] ) ? 1 : 0;
        $cat_args['pad_counts']         = 1;
        $cat_args['show_option_none']   = __('No product categories exist.', 'woocommerce');
        $cat_args['current_category']   = ( $this->current_cat ) ? $this->current_cat->term_id : '';
        $cat_args['current_category_ancestors'] = $this->cat_ancestors;

        echo '<ul class="product-categories">';

        wp_list_categories( apply_filters( 'woocommerce_product_categories_widget_args', $cat_args ) );

        echo '</ul>';

    }

    echo $after_widget;
}


/**
 * update function.
 *
 * @see WP_Widget->update
 * @access public
 * @param array $new_instance
 * @param array $old_instance
 * @return array
 */
function update( $new_instance, $old_instance ) {
    $instance = $old_instance;
    $instance['title'] = strip_tags($new_instance['title']);
    $instance['orderby'] = strip_tags($new_instance['orderby']);
    $instance['count'] = !empty($new_instance['count']) ? 1 : 0;
    $instance['hierarchical'] = !empty($new_instance['hierarchical']) ? true : false;
    $instance['dropdown'] = !empty($new_instance['dropdown']) ? 1 : 0;
    $instance['show_children_only'] = !empty($new_instance['show_children_only']) ? 1 : 0;

    return $instance;
}


/**
 * form function.
 *
 * @see WP_Widget->form
 * @access public
 * @param array $instance
 * @return void
 */
function form( $instance ) {
    //Defaults
    $instance = wp_parse_args( (array) $instance, array( 'title' => '') );
    $title = esc_attr( $instance['title'] );
    $orderby = isset( $instance['orderby'] ) ? $instance['orderby'] : 'order';
    $count = isset($instance['count']) ? (bool) $instance['count'] :false;
    $hierarchical = isset( $instance['hierarchical'] ) ? (bool) $instance['hierarchical'] : false;
    $dropdown = isset( $instance['dropdown'] ) ? (bool) $instance['dropdown'] : false;
    $show_children_only = isset( $instance['show_children_only'] ) ? (bool) $instance['show_children_only'] : false;

?>

get_field_id('title'); ?>"> get_field_id('title') ); ?>" name="get_field_name('title') ); ?>" type="text" value="" />

    <p><label for="<?php echo $this->get_field_id('orderby'); ?>"><?php _e('Order by:', 'woocommerce') ?></label>
    <select id="<?php echo esc_attr( $this->get_field_id('orderby') ); ?>" name="<?php echo esc_attr( $this->get_field_name('orderby') ); ?>">
        <option value="order" <?php selected($orderby, 'order'); ?>><?php _e('Category Order', 'woocommerce'); ?></option>
        <option value="name" <?php selected($orderby, 'name'); ?>><?php _e('Name', 'woocommerce'); ?></option>
    </select></p>

    <p><input type="checkbox" class="checkbox" id="<?php echo esc_attr( $this->get_field_id('dropdown') ); ?>" name="<?php echo esc_attr( $this->get_field_name('dropdown') ); ?>"<?php checked( $dropdown ); ?> />
    <label for="<?php echo $this->get_field_id('dropdown'); ?>"><?php _e( 'Show as dropdown', 'woocommerce' ); ?></label><br />

    <input type="checkbox" class="checkbox" id="<?php echo esc_attr( $this->get_field_id('count') ); ?>" name="<?php echo esc_attr( $this->get_field_name('count') ); ?>"<?php checked( $count ); ?> />
    <label for="<?php echo $this->get_field_id('count'); ?>"><?php _e( 'Show post counts', 'woocommerce' ); ?></label><br />

    <input type="checkbox" class="checkbox" id="<?php echo esc_attr( $this->get_field_id('hierarchical') ); ?>" name="<?php echo esc_attr( $this->get_field_name('hierarchical') ); ?>"<?php checked( $hierarchical ); ?> />
    <label for="<?php echo $this->get_field_id('hierarchical'); ?>"><?php _e( 'Show hierarchy', 'woocommerce' ); ?></label><br/>

    <input type="checkbox" class="checkbox" id="<?php echo esc_attr( $this->get_field_id('show_children_only') ); ?>" name="<?php echo esc_attr( $this->get_field_name('show_children_only') ); ?>"<?php checked( $show_children_only ); ?> />
    <label for="<?php echo $this->get_field_id('show_children_only'); ?>"><?php _e( 'Only show children for the current category', 'woocommerce' ); ?></label></p>

}

Answer 1

A bit late but perhaps this might still help someone...

If you don't mind hardcoding the parent category name, slug and ID (e.g. "All", "designer","38") this works for creating a dropdown to jump to child categories of the specified ID:

<?php   
$terms = get_terms( 'product_cat', 'child_of=38' );
if ( $terms ) {
    print( '<select name="product_cat" id="dropdown_product_cat">' );
    print( '<option value="designer" selected="selected">All</option>' );
    foreach ( $terms as $term ) {
        printf( '<option value="%s">%s</option>', esc_attr( $term->slug ), esc_html( $term->name ) );
    }
    print( '</select>' );
} ?>
<script type="text/javascript">
/* <![CDATA[ */
        var product_cat_dropdown = document.getElementById("dropdown_product_cat");
        function onProductCatChange() {
                if ( product_cat_dropdown.options[product_cat_dropdown.selectedIndex].value !=='' ) {
                        location.href = "<?php echo home_url(); ?>/?product_cat="+product_cat_dropdown.options[product_cat_dropdown.selectedIndex].value;
                }
        }
        product_cat_dropdown.onchange = onProductCatChange;
/* ]]> */
</script>