Creating a WordPress Widget to Show a Random Post

Making a widget to show a random post uses two underlying concepts you need to get familiar with to be good at WordPress development: making use of WP_Query objects, and making widgets. If you've not checked them before, check out our Quick Guides which more thoroughly introduce both:

If you have, check out this video where I explain the pretty simple process I use to making a Random Post Widget:

How to Make a Random Post WordPress Widget Step-by-Step

Follow the steps listed in the first Quick Guide about widgets.

At the start of the widget method, add the line $query = new WP_Query. This will create for you a new object, $query, an instantiation of the WP_Query class (see the WP_Query link in further reading if that confuses you).

Add argument to the WP_Query line. That means to add to the line above so it now reads: $query = new WP_Query( $q_args );. Then you'll also need to create the $q_args variable. That'll look like: $q_args = array( 'orderby' => 'rand', 'posts_per_page' => '1', );

What that does is create some arguments. posts_per_page makes our WP_Query only return one item. orderby => 'rand' makes the function get a random one (by putting all of them into a random order).

Then we need to make a loop. What this means is that we need to use while ($query->have_posts()) to contain a series of instructions. The first of those instructions will be $query->the_post() which "primes" the post for us to access with functions like the_title(). Then we're going to replace the display directions from the last post, so the title and excerpt of the post is shown. That leads to a block like this: echo $args['before_widget']; echo $args['before_title']; the_title(); echo $args['after_title']; echo get_the_excerpt(); echo $args['after_widget'];

We make sure that after the end of the loop we call wp_reset_postdata(). This undoes our "pollution" in $query->the_post() so that the rest of the site doesn't act funky because of our widget. It's just good hygiene.

Full Code for Making our Widget class QG_Widget extends WP_Widget { /** * Sets up the widgets name etc */ public function __construct() { $widget_ops = array( 'classname' => 'qg_widget', 'description' => 'This is a widget for a quick guide', ); parent::__construct( 'qg_widget', 'Quick Guide Widget', $widget_ops ); } /** * Outputs the content of the widget * * @param array $args * @param array $instance */ public function widget( $args, $instance ) { $q_args = array( 'orderby' => 'rand', 'posts_per_page' => '1', ); $query = new WP_Query( $q_args ); while ($query->have_posts()) { $query->the_post(); echo $args['before_widget']; echo $args['before_title']; the_title(); echo $args['after_title']; echo get_the_excerpt(); echo $args['after_widget']; } wp_reset_postdata(); } } add_action( 'widgets_init', function(){ register_widget( 'QG_Widget' ); }); Further Reading on Widgets and WP_Query

The Complete Guide to Creating WordPress Widgets and Widget Areas

Working with WP_Query

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