+ * @param int $thumbnail_id ID of the attachment used for thumbnail
+ * @return string html
+ */
+function _wp_post_thumbnail_html( $thumbnail_id = NULL ) {
+ global $content_width, $_wp_additional_image_sizes, $post_ID;
+ $set_thumbnail_link = '<p class="hide-if-no-js"><a title="' . esc_attr__( 'Set featured image' ) . '" href="' . esc_url( get_upload_iframe_src('image') ) . '" id="set-post-thumbnail" class="thickbox">%s</a></p>';
+ $content = sprintf($set_thumbnail_link, esc_html__( 'Set featured image' ));
+
+ if ( $thumbnail_id && get_post( $thumbnail_id ) ) {
+ $old_content_width = $content_width;
+ $content_width = 266;
+ if ( !isset( $_wp_additional_image_sizes['post-thumbnail'] ) )
+ $thumbnail_html = wp_get_attachment_image( $thumbnail_id, array( $content_width, $content_width ) );
+ else
+ $thumbnail_html = wp_get_attachment_image( $thumbnail_id, 'post-thumbnail' );
+ if ( !empty( $thumbnail_html ) ) {
+ $ajax_nonce = wp_create_nonce( "set_post_thumbnail-$post_ID" );
+ $content = sprintf($set_thumbnail_link, $thumbnail_html);
+ $content .= '<p class="hide-if-no-js"><a href="#" id="remove-post-thumbnail" onclick="WPRemoveThumbnail(\'' . $ajax_nonce . '\');return false;">' . esc_html__( 'Remove featured image' ) . '</a></p>';
+ }
+ $content_width = $old_content_width;
+ }
+
+ return apply_filters( 'admin_post_thumbnail_html', $content );
+}
+
+/**
+ * Check to see if the post is currently being edited by another user.
+ *
+ * @since 2.5.0
+ *
+ * @param int $post_id ID of the post to check for editing