保存帖子时，将“特色图片”设置为第一个ACF图库

Question

我在这里找到了这个功能。我正在使用ACF pro。

更新：我根据下面的注释添加了变量，这消除了错误，但是函数仍然不工作。

功能。php:

add_action( 'save_post', 'set_featured_image_from_gallery' );

function set_featured_image_from_gallery() {
  $post = get_post(); //Edit according to comment below      
  $has_thumbnail = get_the_post_thumbnail($post->ID);

  if ( !$has_thumbnail ) {

    $images = get_field('gallery', false, false);
    $image_id = $images[0];

    if ( $image_id ) {
      set_post_thumbnail( $post->ID, $image_id );
    }
  }
}

保存帖子时出现错误消息（按“更新”-按钮）：

注意：未定义的变量：在第600行 /Applications/MAMP/htdocs/pf-blank/wp/wp-content/themes/PF-Blank-theme/functions.php

注意：试图在/Applications/MAMP/htdocs/pf blank/wp/wp content/themes/pf blank theme/functions中获取非对象的属性。php在线600

警告：无法修改标题信息-标题已由/Applications/MAMP/htdocs/pf blank/wp/wp content/themes/pf blank theme/functions.php:600）中的/Applications/MAMP/htdocs/pf blank/wp admin/post发送。php在线197

警告：无法修改标题信息-标题已由/Applications/MAMP/htdocs/pf blank/wp/wp content/themes/pf blank theme/functions.php:600中的/Applications/MAMP/htdocs/pf blank/wp includes/pluggable发送。php在线1174

Answer 1

您需要通过给出参数来传递get_posts函数中的参数。

请尝试以下代码：

function set_featured_image_from_gallery() {

    $args = array( 'posts_per_page' => 10, 'order'=> 'ASC');
    $postslist = get_posts( $args );
    foreach ( $postslist as $post ) :
      $has_thumbnail = get_the_post_thumbnail($post->ID);

      if ( !$has_thumbnail ) {

        $images = get_field('gallery', false, false);
        $image_id = $images[0];

        if ( $image_id ) {
          set_post_thumbnail( $post->ID, $image_id );
        }
      }
      endforeach; 
    }

    add_action( 'save_post', 'set_featured_image_from_gallery' );