observable-array | lightweight JS observable array constructor with methods

I need to push object in ngFor but I got error Property 'push' does not exist on type 'Observable'. Stackblitz demo code

HTML

I am trying to load topics (just string values) from a backend and display them in the ListPicker. However the ListPicker won't update it's items which should be displayed.

The code is as follows:

I have a radautocomplete in one of my pages and I'm using bottom-navigation in my app.

The first time I navigate to that page is fine, but after that, when I navigate to that page, the suggestions menu automatically pops open as if I had typed something in the autocomplete but I have not. I even put a textfields above that in my form to steal the focus but that didn't make things any better.

Here is a playground sample

In case playground breaks in the future:

App.vue

main-page.xml

After watching many tutorials and trying out a lot of code snippets, i am still confused about when and how to use ObservableArray and binding. Trying to get a listview of values from my json array - alert shows them, console displays what i thought it would. the only thing not working is my listview. any assistance by anyone please! posted my javascript and corresponding xml below.

----updated my code. shows an array of six values with one of each in the itemTemplates. how to access every instance? and the keys? need to display key: value pairs and seemingly the keys are missing in the array. anything appreciated!

listview.js

I'm trying to figure out why the alert doesn't fire. The console.log statements work and the ObservableArray updates and that is shown on the ListView screen. I'm running NativeScript 6.3.3 from cli with the nativeScript-barcodescanner plugin on Android. What am I messing up?

barcode-view-model.ts:

For example if I have a simple app with a welcome-page.js and welcome-view-model.js I would start with something like this form the welcome-page.js

I have a Vanilla Nativescript app that I am testing a RadListView on; populating the items from JS.

As soon as I SET the value of the ObservableArray the app just crashes. I have tried to set the value onload as well as on tap. In this example tab on the BOTTOM LABEL; at the moment a label at the top will display the set value so I know that the object does exist; but when trying to bind the data to the list view things go awry.

Below is the base code to replicate this issue; if you uncomment the line:

pageData.set("items", items);

Any direction would be much appreciated.

HOME-PAGE.XML

At this line of the following code @ViewChild('myListView') listViewComponent: RadListViewComponent; I get the this error message:

Expected 2 arguments, but got 1.ts(2554) core.d.ts(8054, 47): An argument for 'opts' was not provided.

As I am a new learner just following a tutorial from 2017, I have no idea about why this happens and how can I fix it? But it seems the implementation of ViewChild() decorator is changed though I don't know how to adapt my code to fix it?