Call function when input is changed on text box? : <p>I'm trying to create a button that changes color when username and password fields have both been entered with some sort of input (IE; neither username or password text boxes are empty)</p>

<p>Is there a way I can get a function to trigger when input of a text box is changed in NativeScript? I've asked at the NativeScript slack, among other sites but I don't seem to get a reply ever.</p>

<p>I thought this was a relatively simple request, especially when I'm using vanilla JS. Surely it must be simpler than using a framework such as Angular or Vue? </p>

<p>I do not want to use a framework, I am looking for a way to do this with plain JS. What have I tried? I've tried <code>onChange=""</code>, <code>textChange=""</code>, <code>change=""</code> but none seem to work.</p>
