WordPress pagination with custom post type?

Question

I have searched all over the web to find some solution, but none of them are working for me, can someone help me with this and explain what is wrong? I've spent 3 hours debugging and didn't find the issue.

Here is my code:

global $paged;
global $wp_query;
wp_reset_query();

$per_page = get_option('posts_per_page');
$cat_cars = get_term_by('slug', 'cars', 'category');
$page_links_total = ceil($cat_cars->count / $per_page);
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;

$args = array(
    'post_type' => 'cars',
    'post_status' => 'publish',
    'cat' => $cat_cars->term_id,
    'orderby' => 'date',
    'order' => 'DESC',
    'posts_per_page' => $per_page,
    'paged' => $paged
);

$page_links = paginate_links(array(
            'base' => add_query_arg('paged', '%#%'),
            'format' => '',
            'prev_text' => __('«'),
            'next_text' => __('»'),
            'end_size' => 2,
            'mid_size' => 1,
            'type' => 'plain',
            'total' => $page_links_total,
            'current' => $paged
        ));

$car_query = new WP_Query($args);

And later i call have_posts, the_post, etc..
This part works, until I go to the second page of my pagination and get nothing found.

Answer 1

I had a similar problem recently and determined the cause to be that when WordPress queries for posts in a category, it looks for posts with post_type equal to 'post' before it reaches the point where you query for post_type 'any' or some custom post type. This doesn't cause a problem on page 1 because even if there are no posts it calls your template. However on page 2 and so forth, it doesn't find any posts of post_type 'post' so it loads the 404 template before your template even gets a chance to modify the post_type parameter.

Is this a bug? That's a good question. I would say so because you should expect that if you register the 'category' taxonomy on other post_types, all post_types would show up in that archive, not just strictly posts.

Hopefully that helps.

Answer 2

I have this code (cleaned) on a site, calling posts from a custom post type, and at the bottom the pagination, if there's more than 10 posts:

<?php $wp_query = new WP_Query();  $wp_query->query('post_type=mycpt&showposts=10'.'&paged='.$paged); 
while ($wp_query->have_posts()) : $wp_query->the_post();?>
<h3><?php the_title(); ?></h3>
<?php the_content();?>  
<?php endwhile; wp_reset_query(); ?>

<?php if (  $wp_query->max_num_pages > 1 ) { ?>
<div id="nav-below" class="navigation">
<div class="nav-previous"><?php next_posts_link( __( '<span class="meta-nav">&laquo;</span> Dicas antigas', 'twentyten' ) ); ?></div>
<div class="nav-next"><?php previous_posts_link( __( 'Dicas mais recentes <span class="meta-nav">&raquo;</span>', 'twentyten' ) ); ?></div>
</div>
<?php } ?>

Hope it can help.