How can I show post views counter?

I want to show custom posts views counter. Also, I want to create a shortcode so that I can show it anywhere. Currently, It shows the custom posts list but with the "0" view. Can it be increased?

Here is the code so far:

function getPostViews($postID){
$author_id = ''; 
$author_posts = get_posts( array(
'author' => $author_id,
'post_type' => 'video'
) );

$counter = 0; 


foreach ( $author_posts as $post )
{
  $views = absint( get_post_meta( $post->ID, 'views', true ) );
  $counter += $views;
  echo "<li style='color:#000;'>{$post->post_title} ({$views})</li>";
}
echo "</ul><hr /><p style='color:#000;'>Total Number of views: <strong> 
{$counter}</strong></p>";
}

add_shortcode('view','getPostViews');