import { Observable } from '@nativescript/core/data/observable' ; import { ObservableArray } from '@nativescript/core/data/observable-array' ; export class MultiTemplatesViewModel extends Observable { private _items : ObservableArray < number > ; get items ( ) : ObservableArray < number > { this . _items = new ObservableArray < number > ( ) ; for ( let i = 0 ; i < 20 ; i ++ ) { this . _items . push ( i ) ; } return this . _items ; } }