A place to store some useful snippets of code for working with WordPress. Just a personal reference. All these codes have been tested by me and they work as intended, unless otherwise noted.
if ( ! function_exists( 'myfirsttheme_setup' ) ) :
/**
* Sets up theme defaults and registers support for various WordPress features.
*
* Note that this function is hooked into the after_setup_theme hook, which runs
* before the init hook. The init hook is too late for some features, such as indicating
* support post thumbnails.
*/
function myfirsttheme_setup() {
/**
* Make theme available for translation.
* Translations can be placed in the /languages/ directory.
*/
load_theme_textdomain( 'myfirsttheme', get_template_directory() . '/languages' );
/**
* Add default posts and comments RSS feed links to <head>.
*/
add_theme_support( 'automatic-feed-links' );
/**
* Enable support for post thumbnails and featured images.
*/
add_theme_support( 'post-thumbnails' );
/**
* Add support for two custom navigation menus.
*/
register_nav_menus( array(
'primary' => __( 'Primary Menu', 'myfirsttheme' ),
'secondary' => __('Secondary Menu', 'myfirsttheme' )
) );
/**
* Enable support for the following post formats:
* aside, gallery, quote, image, and video
*/
add_theme_support( 'post-formats', array ( 'aside', 'gallery', 'quote', 'image', 'video' ) );
}
endif; // myfirsttheme_setup
add_action( 'after_setup_theme', 'myfirsttheme_setup' );
/**
* MyFirstTheme's functions and definitions
*
* @package MyFirstTheme
* @since MyFirstTheme 1.0
*/
/**
* First, let's set the maximum content width based on the theme's design and stylesheet.
* This will limit the width of all uploaded images and embeds.
*/
if ( ! isset( $content_width ) )
$content_width = 800; /* pixels */
if ( ! function_exists( 'myfirsttheme_setup' ) ) :
/**
* Sets up theme defaults and registers support for various WordPress features.
*
* Note that this function is hooked into the after_setup_theme hook, which runs
* before the init hook. The init hook is too late for some features, such as indicating
* support post thumbnails.
*/
function myfirsttheme_setup() {
/**
* Make theme available for translation.
* Translations can be placed in the /languages/ directory.
*/
load_theme_textdomain( 'myfirsttheme', get_template_directory() . '/languages' );
/**
* Add default posts and comments RSS feed links to <head>.
*/
add_theme_support( 'automatic-feed-links' );
/**
* Enable support for post thumbnails and featured images.
*/
add_theme_support( 'post-thumbnails' );
/**
* Add support for two custom navigation menus.
*/
register_nav_menus( array(
'primary' => __( 'Primary Menu', 'myfirsttheme' ),
'secondary' => __('Secondary Menu', 'myfirsttheme' )
) );
/**
* Enable support for the following post formats:
* aside, gallery, quote, image, and video
*/
add_theme_support( 'post-formats', array ( 'aside', 'gallery', 'quote', 'image', 'video' ) );
}
endif; // myfirsttheme_setup
add_action( 'after_setup_theme', 'myfirsttheme_setup' );
Loop through a query twice with rewind_loop.
// Start the main loop
<?php
if ( have_posts() ) : while ( have_posts() ) : the_post();
the_title();
endwhile;
endif;
// Use rewind_posts() to use the query a second time.
rewind_posts();
// Start a new loop
while ( have_posts() ) : the_post();
the_content();
endwhile;
?>
displaying a single post with a list of posts from the same category below the single post.
<?php
// The main query.
if ( have_posts() ) : while ( have_posts() ) : the_post();
the_title();
the_content();
endwhile;
else :
// When no posts are found, output this text.
_e( 'Sorry, no posts matched your criteria.' );
endif;
wp_reset_postdata();
/*
* The secondary query. Note that you can use any category name here. In our example,
* we use "example-category".
*/
$secondary_query = new WP_Query( 'category_name=example-category' );
// The second loop. if ( $secondary_query->have_posts() )
echo '<ul>';
while ( $secondary_query->have_posts() ) :
$secondary_query->the_post();
echo '<li>' . get_the_title() . '</li>';
endwhile;
echo '</ul>';
endif;
wp_reset_postdata();
?>
function wpb_rand_posts() {
$args = array(
'post_type' => 'post',
'orderby' => 'rand',
'posts_per_page' => 5,
);
$the_query = new WP_Query( $args );
if ( $the_query->have_posts() ) {
$string .= '<ul>';
while ( $the_query->have_posts() ) {
$the_query->the_post();
$string .= '<li><a href="'. get_permalink() .'">'. get_the_title() .'</a></li>';
}
$string .= '</ul>';
/* Restore original Post Data */
wp_reset_postdata();
} else {
$string .= 'no posts found';
}
return $string;
}
add_shortcode('wpb-random-posts','wpb_rand_posts');
add_filter('widget_text', 'do_shortcode');
Now you can display random posts inside a WordPress post, page, or text widget using the shortcode [wpb-random-posts].
Custom Taxonomies
//hook into the init action and call create_book_taxonomies when it fires
add_action( 'init', 'create_topics_hierarchical_taxonomy', 0 );
//create a custom taxonomy name it topics for your posts
function create_topics_hierarchical_taxonomy() {
// Add new taxonomy, make it hierarchical like categories
//first do the translations part for GUI
$labels = array(
'name' => _x( 'Topics', 'taxonomy general name' ),
'singular_name' => _x( 'Topic', 'taxonomy singular name' ),
'search_items' => __( 'Search Topics' ),
'all_items' => __( 'All Topics' ),
'parent_item' => __( 'Parent Topic' ),
'parent_item_colon' => __( 'Parent Topic:' ),
'edit_item' => __( 'Edit Topic' ),
'update_item' => __( 'Update Topic' ),
'add_new_item' => __( 'Add New Topic' ),
'new_item_name' => __( 'New Topic Name' ),
'menu_name' => __( 'Topics' ),
);
// Now register the taxonomy
register_taxonomy('topics',array('post'), array(
'hierarchical' => true,
'labels' => $labels,
'show_ui' => true,
'show_admin_column' => true,
'query_var' => true,
'rewrite' => array( 'slug' => 'topic' ),
));
}
//hook into the init action and call create_topics_nonhierarchical_taxonomy when it fires
add_action( 'init', 'create_topics_nonhierarchical_taxonomy', 0 );
function create_topics_nonhierarchical_taxonomy() {
// Labels part for the GUI
$labels = array(
'name' => _x( 'Topics', 'taxonomy general name' ),
'singular_name' => _x( 'Topic', 'taxonomy singular name' ),
'search_items' => __( 'Search Topics' ),
'popular_items' => __( 'Popular Topics' ),
'all_items' => __( 'All Topics' ),
'parent_item' => null,
'parent_item_colon' => null,
'edit_item' => __( 'Edit Topic' ),
'update_item' => __( 'Update Topic' ),
'add_new_item' => __( 'Add New Topic' ),
'new_item_name' => __( 'New Topic Name' ),
'separate_items_with_commas' => __( 'Separate topics with commas' ),
'add_or_remove_items' => __( 'Add or remove topics' ),
'choose_from_most_used' => __( 'Choose from the most used topics' ),
'menu_name' => __( 'Topics' ),
);
// Now register the non-hierarchical taxonomy like tag
register_taxonomy('topics','post',array(
'hierarchical' => false,
'labels' => $labels,
'show_ui' => true,
'show_admin_column' => true,
'update_count_callback' => '_update_post_term_count',
'query_var' => true,
'rewrite' => array( 'slug' => 'topic' ),
));
}
Display Custom Taxonomy
<?php the_terms( $post->ID, 'topics', 'Topics: ', ', ', ' ' ); ?>
≠==========
add_action( 'init', 'create_athlete_taxonomy' );
function create_athlete_taxonomy() {
$labels = array(
'name' => 'Athletes',
'singular_name' => 'Athlete',
'search_items' => 'Search Athletes',
'all_items' => 'All Athletes',
'edit_item' => 'Edit Athlete',
'update_item' => 'Update Athlete',
'add_new_item' => 'Add New Athlete',
'new_item_name' => 'New Athlete Name',
'menu_name' => 'Athlete',
'view_item' => 'View Athlete',
'popular_items' => 'Popular Athlete',
'separate_items_with_commas' => 'Separate athletes with commas',
'add_or_remove_items' => 'Add or remove athletes',
'choose_from_most_used' => 'Choose from the most used athletes',
'not_found' => 'No athletes found'
);
register_taxonomy(
'athlete',
'post',
array(
'label' => __( 'Athlete' ),
'hierarchical' => false,
'labels' => $labels,
'public' => true,
'show_in_nav_menus' => false,
'show_tagcloud' => false,
'show_admin_column' => true,
'rewrite' => array(
'slug' => 'athletes'
)
)
);
}
Widgets
// Register and load the widget
function wpb_load_widget() {
register_widget( 'wpb_widget' );
}
add_action( 'widgets_init', 'wpb_load_widget' );
// Creating the widget
class wpb_widget extends WP_Widget {
function __construct() {
parent::__construct(
// Base ID of your widget
'wpb_widget',
// Widget name will appear in UI
__('WPBeginner Widget', 'wpb_widget_domain'),
// Widget description
array( 'description' => __( 'Sample widget based on WPBeginner Tutorial', 'wpb_widget_domain' ), )
);
}
// Creating widget front-end
public function widget( $args, $instance ) {
$title = apply_filters( 'widget_title', $instance['title'] );
// before and after widget arguments are defined by themes
echo $args['before_widget'];
if ( ! empty( $title ) )
echo $args['before_title'] . $title . $args['after_title'];
// This is where you run the code and display the output
echo __( 'Hello, World!', 'wpb_widget_domain' );
echo $args['after_widget'];
}
// Widget Backend
public function form( $instance ) {
if ( isset( $instance[ 'title' ] ) ) {
$title = $instance[ 'title' ];
}
else {
$title = __( 'New title', 'wpb_widget_domain' );
}
// Widget admin form
?>
<p>
<label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e( 'Title:' ); ?></label>
<input class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $title ); ?>" />
</p>
<?php
}
// Updating widget replacing old instances with new
public function update( $new_instance, $old_instance ) {
$instance = array();
$instance['title'] = ( ! empty( $new_instance['title'] ) ) ? strip_tags( $new_instance['title'] ) : '';
return $instance;
}
} // Class wpb_widget ends here