Code in javascript

I need this example in javascript for nativescript

I'm not sure this is the right place for such a discussion, but I'm having an issue attempting to replicate this functionality using Angular. Is there anyway you could provide examples using Angular as well?

-EDIT-
Nevermind, I figured it out. In Angular, the problem is with using NSTimer for some reason...switching that to a javascript interval seems to have resolved the issue - functionality is replicated in Angular.