NativeScript/apps/ui/app/animation/height-basic-page.ts

import { Label } from '@nativescript/core';

let toggle = false;

export function animateHeight(args) {
	const clicked = args.object as Label;
	clicked
		.animate({
			height: toggle ? 128 : '100%',
			duration: 200,
			curve: 'easeInOut',
		})
		.then(() => {
			clicked.text = toggle ? 'Cool.' : 'Tap here';
		});
	toggle = !toggle;
}