为文章列表页面添加缩略图

WordPress version 2.9引入了文章缩略图的功能。但默认情况下，在文章列表里是不会有缩略图功能的。但是只要我们在function.php里加入以下一段代码，就可以实现下面图片的功能。

并且在添加文章页面，默认右下角也会出现“设置缩略图”的功能 。

下面的代码可以作为插件的代码也可以直接复制进function.php主题文件里。

if ( !function_exists(‘fb_AddThumbColumn’) && function_exists(‘add_theme_support’) ) {

// for post and page
add_theme_support(‘post-thumbnails’, array( ‘post’, ‘page’ ) );

function fb_AddThumbColumn($cols) {

$cols['thumbnail'] = __(‘Thumbnail’);

return $cols;
}

function fb_AddThumbValue($column_name, $post_id) {

$width = (int) 35;
$height = (int) 35;

if ( ‘thumbnail’ == $column_name ) {
// thumbnail of WP 2.9
$thumbnail_id = get_post_meta( $post_id, ‘_thumbnail_id’, true );
// image from gallery
$attachments = get_children( array(‘post_parent’ => $post_id, ‘post_type’ => ‘attachment’, ‘post_mime_type’ => ‘image’) );
if ($thumbnail_id)
$thumb = wp_get_attachment_image( $thumbnail_id, array($width, $height), true );
elseif ($attachments) {
foreach ( $attachments as $attachment_id => $attachment ) {
$thumb = wp_get_attachment_image( $attachment_id, array($width, $height), true );
}
}
if ( isset($thumb) && $thumb ) {
echo $thumb;
} else {
echo __(‘None’);
}
}
}

// for posts
add_filter( ‘manage_posts_columns’, ‘fb_AddThumbColumn’ );
add_action( ‘manage_posts_custom_column’, ‘fb_AddThumbValue’, 10, 2 );

// for pages
add_filter( ‘manage_pages_columns’, ‘fb_AddThumbColumn’ );
add_action( ‘manage_pages_custom_column’, ‘fb_AddThumbValue’, 10, 2 );
}

整理|来自：http://wpengineer.com/display-post-thumbnail-post-page-overview/

本文链接: http://airyland.com/blog/display-post-thumbnail-post-page-overview/

Thanks for the writer's works.感谢原作者的文章。