Nextgen Gallery is a perfect gallery plugin for wordpress. I use it most with my wordpress theme projects. Here i will show you how to display nextgen gallery using php code in your page templates.

Nextgen gallery has a shortcode to add any gallery to your post. But if you want to display the gallery in your header, slider or sidebar you need to customize your theme files a bit. To achive this we will use Custom Field gallery_id.

First you need to enter gallery_id‘s in the custom field and save.

Then open single.php for posts, page.php for pages and add this code where you want your gallery to appear:

  $gallery_id = get_post_meta( $post->ID, 'gallery_id', true); // Get gallery id from custom field data
  if( isset($gallery_id) ){ 
    echo "<div class="post-gallery">";
    echo nggShowGallery( $gallery_id ); // Display the gallery
    echo "</div>";

Save and upload the file to your dedicated server.

This will show a gallery if one is set using custom fields.

If you want a better user experience you can add a metabox for selecting gallery ids.