WordPress ユーザー情報の拡張とアバター画像とその表示 ref: http://qiita.com/gatespace/items/9a586da6b724107727ad

add-user-contactmethods.php

<?php
// Register User Contact Methods
function custom_user_contact_methods( $user_contact_method ) {

    $user_contact_method['facebook'] = __( 'Facebook Username', 'text_domain' );
    $user_contact_method['twitter'] = __( 'Twitter Username', 'text_domain' );
    $user_contact_method['gplus'] = __( 'Google Plus', 'text_domain' );
    $user_contact_method['skype'] = __( 'Skype Username', 'text_domain' );

    return $user_contact_method;

}
add_filter( 'user_contactmethods', 'custom_user_contact_methods' );

author-meta.php

<?php
    // Website
    if ( get_the_author_meta( 'user_url' ) )  {
        echo '<a href="' . esc_url( get_the_author_meta( 'user_url' ) ) . '"><span class="genericon genericon-website"></span></a>';
    }
    // Facebook
    if ( get_the_author_meta( 'facebook' ) )  {
        echo '<a href="' . esc_url( 'https://www.facebook.com/' . get_the_author_meta( 'facebook' ) ) . '"><span class="genericon genericon-facebook"></span></a>';
    }
    // Twitter
    if ( get_the_author_meta( 'twitter' ) )  {
        echo '<a href="' . esc_url( 'https://twitter.com/' . get_the_author_meta( 'twitter' ) ) . '"><span class="genericon genericon-twitter"></span></a>';
    }
    // Google Plus
    if ( get_the_author_meta( 'gplus' ) )  {
        echo '<a href="' . esc_url( get_the_author_meta( 'gplus' ) ) . '"><span class="genericon genericon-googleplus"></span></a>';
    }
    // Skype
    if ( get_the_author_meta( 'skype' ) )  {
        echo '<a href="skype:' . esc_attr( get_the_author_meta( 'skype' ) ) . '?call"><span class="genericon genericon-skype"></span></a>';
    }
?>

writerlist_shortcode.php

<?php
function writerlist_shortcode( $atts ) {
    $output = '';

    // Attributes
    extract( shortcode_atts(
        array(
            'role' => 'Author',
        ),
        $atts
    ) );

    $role = str_replace( array( " ", "　" ), "", $role );
    $role = explode( ',', $role );

    // WP_User_Query arguments
    $user_args = array (
        'role__in' => $role,
        'order'    => 'ASC',
        'orderby'  => 'display_name',
    );

    // Create the WP_User_Query object
    $wp_user_query = new WP_User_Query( $user_args );

    // Get the results
    $authors = $wp_user_query->get_results();

    if ( ! empty( $authors ) ) {
        $output .= '<ul class="author-lists">' . "\n";
        // loop through each author
        foreach ( $authors as $author ) {
            // get all the user's data
            $output .= '<li class="author-info">' . "\n";
            $output .= '<div class="author-avatar">' . get_avatar( get_the_author_meta( 'user_email', $author->ID ) ) . '</div>' . "\n";
            $output .= '<div class="author-bio">'. "\n";
            $output .= '<div class="author-title">' . get_the_author_meta( 'display_name', $author->ID ) . '</div>' . "\n";
            $output .= '<div class="author-description">' . nl2br( get_the_author_meta( 'description', $author->ID ) ) . '</div>' . "\n";
            $output .= '</div>'. "\n";

            $output .= '</li>' . "\n";
        }
        $output .= '</ul>' . "\n";
    }
    return $output;

}
add_shortcode( 'writerlist', 'writerlist_shortcode' );