Ion-scroll vertically

Ionic Framework ionic-v3
1

I am trying to pu a scroll vertically.When i put ion-scroll tag,It shows nothing

Here is ts file

constructor(public navCtrl: NavController,public sms: SMS,public load:LoadingController) {
    this.liste=[{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},{"displayName":"jane"},{"displayName":"james"},{"displayName":"micheal"},{"displayName":"bob"},]
   }

html file

ion-scroll scrollX="true" >
 
<ion-item *ngFor="let item of liste">
  
   {{item.displayName}}
 
</ion-item>
</ion-scroll>

css file

ion-scroll {
  white-space: nowrap !important;
  
}

AS i said it works perfectly without ion scroll

Any idea or suggesttion ?

Thank you in Advance

2

I have missed it because of working hard .It should be scrollY=""true" and height: 100%

Thanks