display certain category on custom template page

Question

i duplicated a portfolio column page template ... On this page I want to show only one category , instead of all categories... I tried a lot, but couldn't get it worked...

this is the original code to show all categories:

<div class="container">

    <ul id="ublportfolio" class="grid cs-style-3">

        <?php 
            query_posts( array( 'post_type' => 'ublalfieportfolio', 'posts_per_page' => -1) );
            if ( have_posts() ) : while ( have_posts() ) : the_post(); 

            global $post;
            $terms = get_the_terms($post->ID, 'ublalfieportfolio-categories');
            $taxclassadd = '';
            foreach($terms as $t){$taxclassadd .= ' ' . $t->slug;}

            $taxclass = 'thisportfolioitem twocol' . $taxclassadd; $str= ltrim ($taxclassadd,' ');
        ?>

        <li <?php post_class($taxclass); ?> id="post-<?php the_ID(); ?>" data-category="<?php echo $str; ?>">
            <figure>

                <?php if(has_post_thumbnail()) { 
                $thumbnail = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'full', false);
                if($thumbnail['1'] > 1024){$thumbnail = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'large', false);} ?>
                <img src="<?php echo $thumbnail['0']; ?>" alt="<?php the_title(); ?>">
                <?php } ?>

                <figcaption>
                    <h3><?php the_title(); ?></h3>
                    <span><?php if($post->post_excerpt){$getcontent = get_the_excerpt();echo $getcontent;} ?></span>
                    <a href="<?php the_permalink(); ?>"><?php _e('View Item','ublalfie'); ?></a>
                </figcaption>

            </figure>
        </li>

        <?php endwhile; endif; ?>

    </ul>

</div>

for example I only want to show : the category-slug = "parketten" and ID = 3

I tried this:

<?php 
          query_posts( array( 'post_type' => 'ublalfieportfolio', 'category_name' => 'terrassen', 'posts_per_page' => -1) );
          if ( have_posts() ) : while ( have_posts() ) : the_post(); 

          global $post;
          $terms = get_the_terms($post->ID, 'parketten');
          $taxclassadd = '';
          foreach($terms as $t){$taxclassadd .= ' ' . $t->slug;}

          $taxclass = 'span4 portfolioitem text-center' . $taxclassadd; $str= ltrim ($taxclassadd,' ');
      ?>

result : shows nothing

<?php 
            query_posts( array( 'post_type' => 'ublalfieportfolio', 'category' => array(3), 'posts_per_page' => -1) );
            if ( have_posts() ) : while ( have_posts() ) : the_post(); 

            global $post;
            $terms = get_the_terms($post->ID, 'parketten');
            $taxclassadd = '';
            foreach($terms as $t){$taxclassadd .= ' ' . $t->slug;}

            $taxclass = 'span4 portfolioitem text-center' . $taxclassadd; $str= ltrim ($taxclassadd,' ');
        ?>

result: shows all categories..

Can someone please give me a solution... thank you very much

Answer 1

You should not use category parameter to query custom taxonomy instead you should use tax_query parameter or directly custom taxonomy name as shown in the following query.

query_posts( array( 'post_type' => 'ublalfieportfolio', 'ublalfieportfolio-categories' => 'parketten', 'posts_per_page' => -1) );

Refer this page to know how to use custom taxonomy parameter in custom query.