import { EventData } from '@nativescript/core/data/observable'; import { Page } from '@nativescript/core/ui/page'; import { BottomNavigation } from '@nativescript/core/ui/bottom-navigation'; export function goToFirst(args: EventData) { const page = (args.object).page; const bottomNav = page.getViewById('bottomNav'); bottomNav.selectedIndex = 0; } export function goToSecond(args: EventData) { const page = (args.object).page; const bottomNav = page.getViewById('bottomNav'); bottomNav.selectedIndex = 1; }