Copied files from plugin to theme not working

Question

To get the template directory, you can use get_template_directory_uri() like this:

$themeDir = get_template_directory_uri();

// ...
$themeItems = $themeDir . '/my_folder/my_items.php';
if (file_exists($themeItems))
  return $themeItems;
else
  return $pluginDir . '/template/my_items.php';

For more info visit Function Reference/get template directory uri.. If you want to place your PHP code in your theme directory, the better place for that is the “functions.php” file, or include($theFile) in the “functions.php” where you want to place your PHP code.