Android Question Refresh WebView using pull-to-refresh

Should be possible with this library: https://www.b4x.com/android/forum/threads/flingablewebview.33406

I've tried to use flingablewebview to make a pull to refresh, but I can't see how it would work... It indicates movement and velocity, but how does it know if the user is at the top of the webpage?

Has anyone been able to make this work? Somehow you have to know that it should only perform a pull to refresh if at the top of the webpage..

If anyone can point me in the right direction or give me a hint that would be great!