MultiPostThumbnail and the_post_thumbnail

Question

I am using built-in Wordpress function to add (small) thumbnails to each post. In addition to the post thumbnail I am using MultiPostThumbnail plugin to add custom category (large) image.

Since not all posts have thumbnails or "secondary image" (as it is called by MultiPostThumbnail plugin) I would like to display thumbnails (either large or small) in this order:

1. If I a post has large (MultiPostThumbnails) thumbnail and (small) thumbnail display only (large) thumbnail.

2. If a post doesn't have a (large) thumbnail display the (small) thumbnail.

I hope now it makes more sense. It's a simple if statement but I can't get it to work. Here is a "pseudo-code".

<?php if (class_exists('MultiPostThumbnails')
   && MultiPostThumbnails::has_post_thumbnail('post', 'secondary-image')) :
      MultiPostThumbnails::the_post_thumbnail('post', 'secondary-image', NULL,  'post-secondary-image-thumbnail');
else {
   the_post_thumbnail();
}
?>

Answer 1

In code you posted you have issue with syntax - you should stick either with braces style or colons style, mixing them is not supported.

if(class_exists('MultiPostThumbnails')
    && MultiPostThumbnails::has_post_thumbnail('post', 'secondary-image')) {

    MultiPostThumbnails::the_post_thumbnail('post', 'secondary-image', NULL, 'post-secondary-image-thumbnail');
} 
else {

    the_post_thumbnail();
}