How to make a second loop in single.php work? - php

Question

-simple blog
-twenty twelve child theme
I need: a second loop in single.php that shows the selected post and all the other posts below.
What I have so far in single.php (results in a blank page) :
<?php get_header(); ?>
<div id="primary" class="site-content">
<div id="content" role="main">
<?php while ( have_posts() ) : the_post(); ?>
<?php get_template_part( 'content', get_post_format() ); ?>
<?php comments_template( '', true ); ?>
<?php endwhile; // end of the loop. ?>
<?php endif; ?>
<?php wp_reset_postdata(); // reset the post data so we can run another query ?>
<?php get_sidebar(); ?>
<?php
// The Second Query
$the_query = new WP_Query();
// The Loop
if ( $the_query->have_posts() ):
while ( $the_query->have_posts() ):
$the_query->the_post(); ?>
<div <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<h1><?php the_title(); ?></h1>
<?php the_content(); ?>
</div>
<?php endwhile; ?>
<?php endif; ?>
<?php wp_reset_postdata(); // Restore original Post ?>
</div><!-- #content -->
</div><!-- #primary -->

Answer 1

This should do the trick:
<?php get_header(); ?>
<div id="primary" class="site-content">
<div id="content" role="main">
<?php while ( have_posts() ) : the_post(); ?>
<div <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<h1><?php the_title(); ?></h1>
<?php the_content(); ?>
</div>
<?php comments_template( '', true ); ?>
<?php endwhile; // end of the loop. ?>
<?php wp_reset_postdata(); // reset the post data so we can run another query ?>
<?php
$args_second = array(
'posts_per_page' => -1,
);
// The Second Query
$second_query = new WP_Query( $args_second );
// The Loop
if ( $second_query->have_posts() ):
while ( $second_query->have_posts() ):
$second_query->the_post(); ?>
<div <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<h1><?php the_title(); ?></h1>
<?php the_content(); ?>
</div>
<?php endwhile; ?>
<?php endif; ?>
<?php wp_reset_postdata(); // Restore original Post ?>
</div><!-- #content -->
</div><!-- #primary -->
Notes:
You need to properly show the title and content using the_title() and the_content() inside the single loop.
To show other posts, you need to query them, you'll quickly understand by looking at the code above.
I'll leave the styling for you.
It is tested and working.