Ionic 4 horizontal scroll with ngFor

Try using the directive on the actual element that needs to get replicated:

<div class="container">
    <div class="scroll" scrollX="true">
        <span *ngFor="let item of items | async">{{item.ProjectEvent}}</span>
    </div>
</div>

Using flexbox:

div[scrollx=true] {
  display: flex;
  flex-wrap: nowrap;
  overflow-x: auto;
  &::-webkit-scrollbar {
     display: none;
  }
   .scroll-item {
     flex: 0 0 auto;
  }
}

https://codeburst.io/how-to-create-horizontal-scrolling-containers-d8069651e9c6

Maybe try it

<ion-segment scrollable="true">
    <ion-segment-button value="friends">
      <ion-label>Friends</ion-label>
    </ion-segment-button>
</ion-segment>