ajax category filter

The question:

I know this is a big ask for you guys, but i can’t seem to figure this out.

I found this page : http://www.bobz.co/ajax-filter-posts-tag/#comment-28112

it shows how to make a dynamic filter for post tags.

I wanted to change it to post categories, but i can’t seem to get it working.

I placed this code in my functions.php

function ajax_filter_posts_scripts() {
  // Enqueue script
  wp_register_script('afp_script', get_stylesheet_directory_uri() . '/js/ajax-filter-posts.js', false, null, false);
  wp_enqueue_script('afp_script');

  wp_localize_script( 'afp_script', 'afp_vars', array(
        'afp_nonce' => wp_create_nonce( 'afp_nonce' ), // Create nonce which we later will use to verify AJAX request
        'afp_ajax_url' => admin_url( 'admin-ajax.php' ),
      )
  );
}
add_action('wp_enqueue_scripts', 'ajax_filter_posts_scripts', 100);

// Script for getting posts
function ajax_filter_get_posts( $taxonomy ) {

  // Verify nonce
  if( !isset( $_POST['afp_nonce'] ) || !wp_verify_nonce( $_POST['afp_nonce'], 'afp_nonce' ) )
    die('Permission denied');

  $taxonomy = $_POST['taxonomy'];

  // WP Query
  $args = array(
    'category_name' => $taxonomy,
    'post_type' => 'post',
    'posts_per_page' => 10,
  );

  // If taxonomy is not set, remove key from array and get all posts
  if( !$taxonomy ) {
    unset( $args['category_name'] );
  }

  $query = new WP_Query( $args );

  if ( $query->have_posts() ) : while ( $query->have_posts() ) : $query->the_post(); ?>

    <h2><a href="<?php the_permalink(); ?>" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener"><?php the_title(); ?></a></h2>
    <?php the_excerpt(); ?>

  <?php endwhile; ?>
  <?php else: ?>
    <h2>No posts found</h2>
  <?php endif;

  die();
}

add_action('wp_ajax_filter_posts', 'ajax_filter_get_posts');
add_action('wp_ajax_nopriv_filter_posts', 'ajax_filter_get_posts');

and then in my actual page template i put this code:

//in my template file
<?php
$args = array(
    'post_type' => 'post',
    'posts_per_page' => 10,
);

$query = new WP_Query( $args );

function tags_filter() {
    $tax = 'category';
    $terms = get_terms( $tax );
    $count = count( $terms );

    if ( $count > 0 ): ?>
        <div class="post-tags">
        <?php
        foreach ( $terms as $term ) {
            $term_link = get_term_link( $term, $tax );
            echo '<a href="' . $term_link . '" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener" class="tax-filter" title="' . $term->slug . '">' . $term->name . '</a> ';
        } ?>
        </div>
    <?php endif;
}

when i load my page template the site loads my content and shows category filter buttons, but when i click any of the buttons, returns “No Posts found”.

This leads me to believe i did something wrong with my functions file, but i can’t figure it out.

Can anyone see something i’ve done wrong here?

The Solutions:

Below are the methods you can try. The first solution is probably the best. Try others if the first one doesn’t work. Senior developers aren’t just copying/pasting – they read the methods carefully & apply them wisely to each case.

Method 1

Not sure if you’ve solved this or not but I was looking for a way to embed this within a page and filter posts by category.

I got this working so it displays all categories and the posts related. Put that in functions.php

function ajax_filter_posts_scripts() {
  // Enqueue script
  wp_register_script('afp_script', get_template_directory_uri() . '/js/ajax-filter-posts.js', false, null, false);
  wp_enqueue_script('afp_script');

  wp_localize_script( 'afp_script', 'afp_vars', array(
        'afp_nonce' => wp_create_nonce( 'afp_nonce' ), // Create nonce which we later will use to verify AJAX request
        'afp_ajax_url' => admin_url( 'admin-ajax.php' ),
      )
  );
}
add_action('wp_enqueue_scripts', 'ajax_filter_posts_scripts', 100);

// Script for getting posts
function ajax_filter_get_posts( $taxonomy ) {

  // Verify nonce
  if( !isset( $_POST['afp_nonce'] ) || !wp_verify_nonce( $_POST['afp_nonce'], 'afp_nonce' ) )
    die('Permission denied');

  $taxonomy = $_POST['taxonomy'];

  // WP Query
  $args = array(
    'category_name' => $taxonomy,
    'post_type' => 'post',
    'posts_per_page' => 10,
  );
  echo $taxonomy;
  // If taxonomy is not set, remove key from array and get all posts
  if( !$taxonomy ) {
    unset( $args['tag'] );
  }

  $query = new WP_Query( $args );

  if ( $query->have_posts() ) : while ( $query->have_posts() ) : $query->the_post(); ?>
    <h2><a href="<?php the_permalink(); ?>" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener"><?php the_title(); ?></a></h2>
    <?php the_excerpt(); ?>

  <?php endwhile; ?>
  <?php else: ?>
    <h2>No posts found</h2>
  <?php endif;

  die();
}

add_action('wp_ajax_filter_posts', 'ajax_filter_get_posts');
add_action('wp_ajax_nopriv_filter_posts', 'ajax_filter_get_posts');

Then, add this in your page template:

<?php $args = array(
            'post_type' => 'post',
            'posts_per_page' => 10,
        );

        $query = new WP_Query( $args );

        $tax = 'category';
        $terms = get_terms( $tax );
        $count = count( $terms );

        if ( $count > 0 ): ?>
            <div class="post-tags">
            <?php
            foreach ( $terms as $term ) {
                $term_link = get_term_link( $term, $tax );
                echo '<a href="' . $term_link . '" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener" class="tax-filter" title="' . $term->slug . '">' . $term->name . '</a> ';
            } ?>
            </div>
        <?php endif;
        if ( $query->have_posts() ): ?>
        <div class="tagged-posts">
            <?php while ( $query->have_posts() ) : $query->the_post(); ?>

            <h2><a href="<?php the_permalink(); ?>" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener" rel="nofollow noreferrer noopener"><?php the_title(); ?></a></h2>
            <?php the_excerpt(); ?>

            <?php endwhile; ?>
        </div>

        <?php else: ?>
            <div class="tagged-posts">
                <h2>No posts found</h2>
            </div>
        <?php endif; ?>

Hope that helps solve your problems!

Method 2

In the tags_filter change this
$tax = ‘post_tag’;
to this
$tax = ‘category’;

Then in the WP Query change this
‘tag’ => $taxonomy,
to this
‘category’ => $taxonomy,

Works fine for me…


All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

Leave a Comment