Wordpressのプラグイン「newpost-catch」の改造版ソースコード

newpost-catch-class.php

<?php
//NewpostCatch class
if ( !class_exists('NewpostCatch') ) {
	class NewpostCatch extends WP_Widget {

		// variables
		var $pluginDir = "";

		// structure
		function __construct() {
			// widget settings
			$widget_ops = array( 'description' => 'Thumbnails in new articles.' );

			// widget actual processes
			parent::__construct(false, $name = 'Newpost Catch', $widget_ops );

			// plugin path
			if ( empty($this->pluginDir) ) $this->pluginDir = WP_PLUGIN_URL . '/newpost-catch';

			// default thumbnail
			$this->default_thumbnail = apply_filters('npc_thumb', $this->pluginDir . '/no_thumb.png' );
			
			// print stylesheet
			add_action( 'get_header', array( &$this, 'enqueue_stylesheet' ) );

			// activate textdomain for translations
			add_action( 'init', array( &$this, 'NewpostCatch_textdomain') );
		}

		// localization
		function NewpostCatch_textdomain() {
			load_plugin_textdomain ( 'newpost-catch', false, basename( rtrim(dirname(__FILE__), '/') ) . '/languages' );
		}

		// enqueue_stylesheet
		function enqueue_stylesheet() {
			if( get_option( 'widget_newpostcatch' ) ){
				$options = array_filter( get_option( 'widget_newpostcatch' ) );
				unset( $options['_multiwidget'] );
				foreach( $options as $key => $val ) {
					$options[$key] = $val['css']['active'];
				}
				if( in_array('on' , $options) ){
					$css_path = plugins_url('newpost-catch/style.css');
				} else {
					$css_path = ( @file_exists( STYLESHEETPATH.'/css/newpost-catch.css' ) ) ? get_stylesheet_directory_uri() . '/css/newpost-catch.css' : '' ;
				}

				// register CSS
				wp_register_style( 'newpost-catch', $css_path, array() );
				wp_enqueue_style( 'newpost-catch' );
			}
		}

		//thumbnail
		function no_thumb_image() {
			ob_start();
			ob_end_clean();
			preg_match_all( '/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', get_the_content(), $matches );

			if( isset($matches[1][0]) && !is_wp_error($matches[1][0]) ){
				$set_img = $matches[1][0];
			} else {
				$set_img = $this->default_thumbnail;
			}
			return $set_img;
		}
	
		// create widget
		function widget($args, $instance) {
			extract( $args );

			$title		= apply_filters( 'NewpostCatch_widget_title', $instance['title'] );
			$width		= apply_filters( 'NewpostCatch_widget_width', $instance['width'] );
			$height 	= apply_filters( 'NewpostCatch_widget_height', $instance['height'] );
			$number 	= apply_filters( 'NewpostCatch_widget_number', $instance['number'] );
			$ignore 	= apply_filters( 'NewpostCatch_widget_ignore', $instance['ignore_check']['active'] );
			$css		= apply_filters( 'NewpostCatch_widget_css', $instance['css'] );
			$cat		= apply_filters( 'NewpostCatch_widget_cat', $instance['cat'] );
			if( !empty( $instance['post_type'] ) ){
				$post_type	= apply_filters( 'NewpostCatch_widget_post_type', $instance['post_type'] );
			} else {
				$post_type	= apply_filters( 'NewpostCatch_widget_post_type', 'post' );
			}

			echo $before_widget;

			if ( $title ) echo $before_title . $title . $after_title;
			$sticky = get_option( 'sticky_posts' );
			if( $ignore == !false ){
				$npc_query = new WP_Query( array(
					'post_type' => $post_type,
					'cat' => $cat,
					'posts_per_page' => $number,
					'ignore_sticky_posts' => 0,
					'orderby' => 'date',
					'order' => 'DESC'
				));
			} else {
				$npc_query = new WP_Query( array(
					'post_type' => $post_type,
					'cat' => $cat,
					'posts_per_page' => $number,
					'post_not_in' => $sticky,
					'ignore_sticky_posts' => 1,
					'orderby' => 'date',
					'order' => 'DESC'
				));
			}
?>
<ul id="npcatch">
<?php
	if( $npc_query->have_posts() ) :
		while( $npc_query->have_posts() ) : $npc_query->the_post();
			$date = ( $instance['date']['active'] == true ) ? '<span class="date">' . get_the_time( get_option('date_format') ) . '</span>' : '';

			if( has_post_thumbnail() ) {
				$thumb_id = get_post_thumbnail_id();
				$thumb_url = wp_get_attachment_image_src($thumb_id);
				$thumb_url = $thumb_url[0];
			} else {
				$thumb_url = $this->no_thumb_image();
			}
?>
<li><a href="<?php echo esc_url( get_permalink() ); ?>" title="<?php esc_attr( the_title() ); ?>"><img src="<?php echo esc_url( $thumb_url ); ?>" width="<?php echo esc_attr( $width ); ?>" height="<?php echo esc_attr( $height ); ?>" alt="<?php the_title(); ?>" title="<?php the_title(); ?>"/><span class="title"><?php the_title(); echo $date; ?></span></a></li>
<?php 
		endwhile;
	else :
?>
<p>no post</p>
<?php endif; wp_reset_postdata(); ?>
</ul>

<?php
			echo $after_widget;
		}

		/** @see WP_Widget::update **/
		// updates each widget instance when user clicks the "save" button
		function update($new_instance, $old_instance) {

			$instance = $old_instance;

			$instance['title']			= ($this->magicquotes) ? htmlspecialchars( stripslashes(strip_tags( $new_instance['title'] )), ENT_QUOTES ) : htmlspecialchars( strip_tags( $new_instance['title'] ), ENT_QUOTES );
			$instance['width']			= is_numeric($new_instance['width']) ? $new_instance['width'] : 10;
			$instance['height']			= is_numeric($new_instance['height']) ? $new_instance['height'] : 10;
			$instance['number']			= is_numeric($new_instance['number']) ? $new_instance['number'] : 5;

			if( preg_match("/^[0-9]|,|-/", $new_instance['cat']) ){
				$instance['cat'] 		= $new_instance['cat'];
			} else {
				$instance['cat'] 		= "";
			}

			$instance['date']['active']		= $new_instance['date'];
			$instance['ignore_check']['active']	= $new_instance['ignore_check']['active'];
			$instance['css']['active']		= $new_instance['css'];
			$instance['post_type']			= !empty($new_instance['post_type']) ? $new_instance['post_type'] : 'post';

			update_option('newpost_catch', $instance);

			return $instance;
		}

		/** @see WP_Widget::form **/
		function form($instance) {

			// define default value
			$defaults = array(
						'title'		=> __('LatestPost(s)' , 'newpost-catch'),
						'width'		=> 10,
						'height'	=> 10,
						'number'	=> 5,
						'date'		=> array( 'active' => false ),
						'ignore_check'	=> array( 'active' => false ),
						'css'		=> array( 'active' => true ),
						'cat'		=> NULL,
						'post_type'	=> 'post',
				    );

			$instance = wp_parse_args( (array) $instance, $defaults );
?>
			<p>
			<label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title' , 'newpost-catch'); ?></label>
			<input id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" type="text" class="widefat" value="<?php echo esc_attr($instance['title']); ?>" />
			</p>
			<p>
			<?php _e('Thumbnail Size' , 'newpost-catch'); ?><br />
			<label for="<?php echo $this->get_field_id('width'); ?>"><?php _e('Width' , 'newpost-catch'); ?></label>
			<input id="<?php echo $this->get_field_id('width'); ?>" name="<?php echo $this->get_field_name( 'width' ); ?>" type="text" style="width:50px" value="<?php echo esc_attr($instance['width']); ?>" /> px
			<br />
			<label for="<?php echo $this->get_field_id('height'); ?>"><?php _e('Height' , 'newpost-catch'); ?></label>
			<input id="<?php echo $this->get_field_id('height'); ?>" name="<?php echo $this->get_field_name('height'); ?>" type="text" style="width:50px;" value="<?php echo esc_attr($instance['height']); ?>" /> px
			</p>
			<p>
			<label for="<?php echo $this->get_field_id('number'); ?>"><?php _e('Show post(s)' , 'newpost-catch'); ?></label>
			<input style="width:30px;" id="<?php echo $this->get_field_id('number'); ?>" name="<?php echo $this->get_field_name('number'); ?>" type="text" value="<?php echo esc_attr($instance['number']); ?>" /> <?php _e('Post(s)', 'newpost-catch'); ?>
			</p>
			<p>
			<input type="checkbox" class="checkbox" <?php echo ($instance['date']['active']) ? 'checked="checked"' : ''; ?> id="<?php echo $this->get_field_id( 'date' ); ?>" name="<?php echo $this->get_field_name( 'date' ); ?>" /> <label for="<?php echo $this->get_field_id( 'date' ); ?>"><?php _e('Display date', 'newpost-catch'); ?></label>
			</p>
			<p>
			<input type="checkbox" class="checkbox" <?php echo ($instance['ignore_check']['active']) ? 'checked="checked"' : ''; ?> id="<?php echo $this->get_field_id( 'ignore_check' ); ?>" name="<?php echo $this->get_field_name( 'ignore_check' ); ?>" /> <label for="<?php echo $this->get_field_id( 'ignore_check' ); ?>"><?php _e('Display sticky post', 'newpost-catch'); ?></label>
			</p>
			<p>
	    <input type="checkbox" class="checkbox" <?php if($instance['css']['active']){ echo 'checked="checked"'; } else { echo ''; } ?> id="<?php echo $this->get_field_id( 'css' ); ?>" name="<?php echo $this->get_field_name( 'css' ); ?>" /> <label for="<?php echo $this->get_field_id( 'css' ); ?>"><?php _e('Use default css', 'newpost-catch'); ?></label>
			</p>
			<?php _e('Post types' , 'newpost-catch'); ?><br />
<?php
	$args = array(
		'public'   => true,
	);

	$output = 'objects';
	$operator = 'and';

	$post_types = get_post_types( $args, $output, $operator );
	foreach ( $post_types as $post_type ) {
		if( $post_type->name !== 'attachment' ){
?>
   <p><input type="radio" id="<?php echo $this->get_field_name($post_type->name); ?>" name="<?php echo $this->get_field_name('post_type'); ?>" value="<?php echo $post_type->name; ?>" <?php echo ( $instance['post_type'] == $post_type->name ) ? 'checked="checked"' : ''; ?> > <label for="<?php echo $this->get_field_name($post_type->name); ?>"><?php echo $post_type->labels->singular_name . '(' . $post_type->name . ')'; ?></label></p>
<?php
		}
	}
?>
<?php if( $instance['post_type'] == 'post' ){ ?>
			<p>
			<label for="<?php echo $this->get_field_id('cat'); ?>"><?php _e('Display category(ies)' , 'newpost-catch'); ?></label>
			<input id="<?php echo $this->get_field_id('cat'); ?>" name="<?php echo $this->get_field_name('cat'); ?>" type="text" class="widefat" value="<?php echo esc_attr($instance['cat']); ?>" />
			<span><a href="<?php echo get_bloginfo('url') . '/wp-admin/edit-tags.php?taxonomy=category'; ?>"><?php _e('Check the category ID' , 'newpost-catch'); ?></a></span>
			</p>
<?php } ?>
			<p>
				<?php _e('Use shortcode' , 'newpost-catch'); ?>
				<?php _e('Can use the shortcode in a textwidget and theme files.' , 'newpost-catch'); ?> <a href="http://wordpress.org/plugins/newpost-catch/faq/" target="_blank">FAQ</a>
			</p>
			<p>
				<?php _e('Contact/Follow' , 'newpost-catch'); ?>
				<a href="https://twitter.com/NewpostCatch" target="_blank">Twitter</a>
				<a href="https://www.facebook.com/NewpostCatch" target="_blank">Facebook</a>
			</p>
<?php
		}
	}
}

if ( !class_exists( 'NewpostCatch_SC' ) ) {
	class NewpostCatch_SC {
		function __construct() {
			add_shortcode( 'npc', array( &$this, 'npc_sc' ) );
		}
				
		function npc_sc($atts) {
			$npc_construct = new NewpostCatch();
		
			// default value
			extract( shortcode_atts( array(
				'id' => 'npcatch',
				'post_type' => 'post',
				'cat' => NULL,
				'width' => 10,
				'height' => 10,
				'posts_per_page' => 5,
				'sticky' => 0,
				'offset' => 0,
				'orderby' => 'date',
				'order' => 'DESC',
				'date' => 0,
				'dynamic' => 0,
				'meta_key' => '',
			), $atts ) );

			if( is_array($atts) && array_key_exists('dynamic',$atts) && $atts['dynamic'] == 1 && get_post_type() == 'post' && is_single() ){
				$cat = get_the_category();
				$cat = $cat[0];
				$cat = $cat->cat_ID;
			} else {
				if( is_null($cat) ){
					$cat = NULL;
				}
			}

			if( is_array($atts) && array_key_exists('sticky',$atts) && $atts['sticky'] == 1 ){
				$sticky = 0;
			} else {
				$sticky = 1;
			}

			// query
			$npc_sc_query = new WP_Query( array(
				'post_type' => $post_type,
				'cat' => $cat,
				'offset' => $offset,
				'posts_per_page' => $posts_per_page,
				'ignore_sticky_posts' => $sticky,
				'orderby' => $orderby,
				'order' => $order,
				'meta_key' => $meta_key,
				'post_status' => 'publish'
			));

			$html = '';
			if( $npc_sc_query->have_posts() ) :
				$html .= '<ul id="' . $id . '">';
				while( $npc_sc_query->have_posts() ) :
					$npc_sc_query->the_post();
			
					$get_date = ( $date == true ) ? '<span class="date">' . esc_html( get_the_time( get_option('date_format') ) ) . '</span>' : '';

					$thumb_url = '';
					if( has_post_thumbnail( get_the_ID() ) ) {
						$thumb_id = get_post_thumbnail_id( get_the_ID() );
						$thumb_url = wp_get_attachment_image_src($thumb_id);
						$thumb_url = $thumb_url[0];
					} else {
						$thumb_url = $npc_construct->no_thumb_image();
					}
					
					$html .= '<li><a href="' . esc_url( get_permalink() ) . '" title="' . get_the_title() . '">';
					$html .= '<img src="' . esc_url( $thumb_url ) . '" width="' . esc_attr( $width ) . '" height="' . esc_attr( $height ) . '" alt="' . get_the_title() . '" title="' . get_the_title() . '" /></a>';
					$html .= '<span class="title"><a href="' . esc_url( get_permalink() ) . '" title="' . get_the_title() . '">' . get_the_title() . $get_date;
					$html .= '</a></span></li>';
				endwhile;
				$html .= '</ul>';
			endif;
			wp_reset_postdata();
			
			return $html;
		}
	}
}

ショートコード機能にて、meta_keyオプションを追加したものとなります。
機能としてはWP_Queryのmeta_keyオプションと同じものです。
これを追加することでカスタムフィールドを利用した並び替えが可能になります。

また既存の不備である、ショートコードでのWP_Query実行時にpost_statusが設定されていないため、非公開の記事も表示されてしまう問題にも対応しました。
※その他の部分のWP_Queryも同じ問題がありますが、案件で利用する際に対応が不必要でしたので未対応です。

変更点は下記の通りです。（v1.3.3ベース）

270行目
'meta_key' => '',

・298-299行目
'meta_key' => $meta_key, 'post_status' => 'publish'

zuzu様

ご連絡が遅くなりましてすみません。
また、コードのご提供ありがとうございます。

meta_keyのソート機能もあると便利ですし、post_statusも入れたほうがいいですね！
次期バージョンで対応予定とさせていただきます。（対応は来月中旬あたりを予定しています）