Paper-Slider PolymerElements Not Working


Before migrating my Vaadin 8 app from to 14, I wanted to understand how to utilize web components. I followed the instruction per the documentation but I am unable to get the paper-slider or the paper-input polymer element to work. I keep getting the following error Error loading http://localhost:8080/frontend/bower_components/paper-slider/paper-slider.html. The weird thing is the Monaco Editor works. Currently, using maven to download the webjars. Any help with this is greatly appreciated.


Hi Allen,

If you are referring to [this document]
( it has a small mistake which has been fixed and the page will be updated soon. Sorry for that. The fix is that you should add @NpmPackage(value = "@polymer/paper-input", version = "3.0.2") to your HelloWorld class. You can see the fixed document [here]
( ) for now.

Thanks for responding. I will give it a try and let you know if I come across any problems.

Thank you

Hi Mehdi,

I am getting @NpmPackage and @JsModule cannot be resoled to a type error. Is there a flow dependency I am missing in my pom?


NVM…Running on Vaadin 13 and not 14. Sic!

@NpmPackage and @JsModule are introduced in Vaadin 14 only.

Thanks Syam.