How to limit a list and add scroll

Ionic 2

How do I limit the list in quantity of records, to add a roll to continue rolling if necessary?

          <ion-item-divider color="light">Group</ion-item-divider>
          <ion-item *ngFor="let g of groups" (click)="group(g)">
            <ion-icon name="checkmark" item-right *ngIf="selected && ==="></ion-icon>

@wmanesco I use AngularFire library for example, in general this is done on the controller of this view to limit for example by order, or number=10, before you load it it on the view with the ngIf* command

Hope it helps