apps_views_posts_show.phtml

<?php echo $this->dialog->render("dialog", "Basic dialog", "This is the default dialog which is useful for displaying information. The dialog window can be moved, resized and closed with the 'x' icon.") ?>

library_Widgets_Dialog.php

<?php

//http://jqueryui.com/dialog/

namespace MyApp\Widgets;

class Dialog 
{
  
  public function render($name, $title, $content)
  {
    echo "<div id="$name" title="$title"><p>$content.</p></div>";
    echo '<script>$(function() {$( "#'.$name.'" ).dialog();});</script>';
  }

}

public_index.php

$di->set('dialog', 'MyApp\Widgets\Dialog');