Loading Wordpress posts with AJAX and offset - php

Question

I'm loading wordpress posts via an AJAX script, everything works great until I try to prevent the latest post from being included in the query. When I try to pass offset=1 to the query I get the same posts repeating everytime the 'More posts' link is clicked.
Here's my custom page template, the first loop creates a single hero post that sits above the AJAX loop:
<?php
/*
Template Name: Home
*/
get_header(); ?>
<div id="primary" class="content-area">
<main id="main" class="site-main" role="main">
<div class="latest-popular">
<a class="active-link">Most recent</a> Most popular
</div>
<section class="hero-image">
<?php $my_query = new WP_Query('orderby=menu_order&posts_per_page=1');
while ($my_query->have_posts()) : $my_query->the_post();
?>
<figure><?php the_post_thumbnail(); ?>
<a href="<?php the_permalink(); ?>" rel="bookmark"><figcaption <?php post_class(); ?>>
<h1><?php the_title(); ?></h1>
<h2><?php the_field('description'); ?></h2>
<p class="credit"><?php the_field('credit'); ?></p>
<span class="length"><?php the_field('running_time'); ?> minutes</span>
</figcaption></a><?php if( $field = get_field('exclusive') ): ?><section id="exc" <?php post_class(); ?>></section><?php endif; ?><!-- <section class="award"></section> -->
</figure>
<?php endwhile; ?>
</section>
</main><!-- #main -->
</div><!-- #primary -->
<!-- Ajax Load More script block -->
<section id="ajax-load-more">
<ul class="listing" data-path="<?php echo get_template_directory_uri(); ?>" data-post-type="post" data-display-posts="10" data-post-not-in="<?php echo $postsNotIn; ?>" data-button-text="More Posts" >
<!-- Load Ajax Posts Here -->
</ul>
</section>
<!-- /Ajax Load More -->
<!-- Ajax -->
<script>
$(function() {
if($("#ajax-load-more").length){
var page = 1,
$loading = true,
$finished = false,
$window = $(window),
$el = $('#ajax-load-more'),
$content = $('#ajax-load-more ul'),
$path = $content.attr('data-path');
if($path === undefined){
$path = '/wp-content/themes/my-theme/ajax-load-more.php';
}
//Define button text
if($content.attr('data-button-text') === undefined){
$button = 'More posts';
}else{
$button = $content.attr('data-button-text');
}
$el.append('<p id="load-more" class="more"><span class="loader"></span><span class="load-more-link">'+$button+'</span></p>');
//Load posts function
var load_posts = function(){
$('#load-more').addClass('loading');
$('#load-more span.text').text("Loading...");
$.ajax({
type : "GET",
data : {
postType : $content.attr('data-post-type'),
category : $content.attr('data-category'),
author : $content.attr('data-author'),
taxonomy : $content.attr('data-taxonomy'),
tag : $content.attr('data-tag'),
postNotIn : $content.attr('data-post-not-in'),
numPosts : $content.attr('data-display-posts'),
pageNumber : page,
},
dataType : "html",
url : $path+"/ajax-load-more.php",
beforeSend : function(){
if(page != 1){
$('#load-more').addClass('loading');
$('#load-more span.text').text("Loading...");
}
},
success : function(data){
$data = $('<span>'+data+'</span>');// Convert data to an object
//alert(data);
if(data.length > 1){
$data.hide();
$content.append($data);
$data.fadeIn(500, function(){
$('#load-more').removeClass('loading');
$('#load-more span.text').text($button);
$loading = false;
});
} else {
$('#load-more').addClass('done');
$('#load-more span.text').text($button);
$loading = false;
$finished = true;
}
},
error : function(jqXHR, textStatus, errorThrown) {
$('#load-more').removeClass('loading');
$('#load-more span.text').text($button);
//alert(jqXHR + " :: " + textStatus + " :: " + errorThrown);
}
});
}
$('#load-more').click(function(){
if(!$loading && !$finished && !$(this).hasClass('done')) {
$loading = true;
page++;
load_posts();
}
});
load_posts();
}
});
</script>
<?php get_footer(); ?>
And the PHP that includes the AJAX loop:
<?php
// Our include
define('WP_USE_THEMES', false);
require_once('../../../wp-load.php');
// Our variables
$postType = (isset($_GET['postType'])) ? $_GET['postType'] : 'post';
$category = (isset($_GET['category'])) ? $_GET['category'] : '';
$author_id = (isset($_GET['author'])) ? $_GET['taxonomy'] : '';
$taxonomy = (isset($_GET['taxonomy'])) ? $_GET['taxonomy'] : '';
$tag = (isset($_GET['tag'])) ? $_GET['tag'] : '';
$exclude = (isset($_GET['postNotIn'])) ? $_GET['postNotIn'] : '';
$numPosts = (isset($_GET['numPosts'])) ? $_GET['numPosts'] : 6;
$page = (isset($_GET['pageNumber'])) ? $_GET['pageNumber'] : 0;
$args = array(
'post_type' => $postType,
'category_name' => $category,
'author' => $author_id,
'posts_per_page' => $numPosts,
'paged' => $page,
'orderby' => 'menu_order',
'order' => 'ASC',
'post_status' => 'publish',
);
// EXCLUDE POSTS
// Create new array of excluded posts
/* Example array from parent page:
$features = array();
foreach( $posts as $post):
setup_postdata($post);
$features[] = $post->ID;
endforeach;
if($features){
$postsNotIn = implode(",", $features);
}
*/
// QUERY BY TAXONOMY
if(empty($taxonomy)){
$args['tag'] = $tag;
}else{
$args[$taxonomy] = $tag;
}
query_posts($args);
?>
<?php
// our loop
if (have_posts()) :
$i =0;
while (have_posts()):
$i++;
the_post();?>
<!-- Do stuff -->
<?php endwhile; endif; wp_reset_query(); ?>
As I mentioned above, adding offset=1 causes the same posts to be called every time the 'more posts' link is clicked, I need the latest post in the loop to be excluded, can anyone shed some light on what I'm doing wrong please?

Answer 1

You must use the data-post-not-in attribute and pass an array of post IDs as Offset does not work with pagination.
Check out the readme on the github repo # https://github.com/dcooney/wordpress-ajax-load-more
An example would be:
$features = array('7238', '6649', '6951'); // Array of posts to exclude
if($features){
$postsNotIn = implode(",", $features); //Implode the posts and set a variable to pass to our data-post-not-in param.
}
And then when you would call the Ajax like this:
<ul class="listing" data-path="<?php echo get_template_directory_uri(); ?>" data-post-type="post" data-display-posts="10" data-post-not-in="<?php echo $postsNotIn; ?>" data-button-text="More posts">

Answer 2

Offset has a tendency to break pagination. There's a great article about this on the codex which should solve your problem. Please see: http://codex.wordpress.org/Making_Custom_Queries_using_Offset_and_Pagination