Ionic latest add item not display in the list top - ionic-framework

Question

Im using ionic 3 for my mobile application. I have an issue with my item list, my issue is when i add a new item it does not show up at the top of the list, it always appears at the bottom , how to do that correctly?
Thanks
example
add Item -
first -A
second-B
its display
A
B
I want to know how can display this type
B
A
item list
<ion-list class="ion-addexe">
<ion-item *ngFor="let bill of Details">
<ion-label>
<p class="ion-lbl" style="position: relative;top:-0.2rem;">{{bill.billdescription}}</p>
</ion-label>
<ion-label>
<p class="ion-lbl" text-right style="position: relative;top:-0.2rem;">$ {{bill.billtotal}}</p>
</ion-label>
</ion-item>
</ion-list>
add item
<div>
<ion-item >
<ion-label id="ion-lbls">Select you want</ion-label>
<ion-select [(ngModel)]="addnewBill_category" okText="Add" cancelText="Close">
<ion-option *ngFor="let bill of Category" value="{{bill.billCategoryID}}">{{bill.CategoryName}}</ion-option>
</ion-select>
</ion-item>
<ion-item >
<ion-label id="ion-lbls">Details</ion-label>
<ion-input type="text" value="" [(ngModel)] = "addnewBill_description" placeholder="Description" text-right></ion-input>
</ion-item>
<ion-item >
<ion-label id="ion-lbls">Date</ion-label>
<ion-datetime displayFormat="MMM DD YYYY" [(ngModel)]="event.addnewbill_Date" placeholder="MMM/DD/YYYY"></ion-datetime>
</ion-item>
<ion-item>
<ion-label id="ion-lbls">Total ($)</ion-label>
<ion-input type="number" [(ngModel)]="addnewBill_amount" value="" placeholder="$0.0" text-right></ion-input>
</ion-item>
</div>
</ion-list>

Answer 1

First of all that is the correct way in which a ngFor works it displays the first element first and the next items at the bottom, because whenever you insert new items inside an array it follows the top to bottom approach. So basically you want to display your array items in reverse order that should be your question
The most simple and easy solution to this is by just using reverse() on your *ngfor. In your case it would be something like this:
<ion-item *ngFor="let bill of Details.reverse()">
...
<ion-item>
or one more solution is using a custom angular pipe which you could apply on the *ngFor and sort your array in reverse order.
import { Pipe, PipeTransform } from '#angular/core';
#Pipe({
name: 'reverse'
})
export class ReversePipe implements PipeTransform {
transform(value) {
if (!value) return;
return value.reverse();
}
}
and then in your html you can use that pipe like this:
<ion-item *ngFor="let bill of Details | reverse">
...
<ion-item>