Google Analytics gtag Event Tracking for PDF Files with javascript

Question

I'm trying to add a simple solution to add event tracking for PDF files to google analytics.

I can't figure out, why the events are not tracked. If I manual add:

<a href="/my-file.pdf" target="_blank" onclick="gtag('event', 'click', {'event_category' : 'PDF download','event_label' : 'label123'});">Download the PDF</a>

to a link, it works fine.

It seems

var path = $(this).attr('href');

causes the issue.

What am I doing wrong?

<script>   
(function($){
    $('a[href$=\'.pdf\']').click(function() {
        var path = $(this).attr('href');
            gtag('event', 'click', {'event_category' : 'PDF download','event_label' : path});
                });
    });
</script>

thanks!