将JSON对象数组绑定到Angular2 nativescript中的视图

我有一个从API返回的JSON对象，如下所示

{
"ID": "GM5VY",
"Passengers": [
 {
"Firstname": "TEST",
"Lastname": "TRAVELLER",
"TotalCount": "1",
FqtT": [
  {
    "MembershipID": "XXXXXX"
  }
],
"Errors": null,
"Information": null,
"Warnings": null
}
],
"Errors": null,
"Information": null,
"Warnings": null
}

我正在使用管道过滤器将此对象转换为数组，并尝试在视图中显示乘客的名字。但我无法找回

<StackLayout *ngFor=" let passengerls of PassengerDetails | objtoarray; let i = index">
    <Label [text]="passengerls?.value?.Passengers ? passengerls?.value?.Passengers[i].Firstname:null"> </Label>                        

</StackLayout>

---

请帮我完成这个

用一种更简单的方法迭代数组怎么样：

<StackLayout *ngFor="let passenger of PassengerDetails.Passengers">
  <Label [text]="passenger.Firstname"></Label>
</StackLayout>

显示您的管道实现？您可以设置一个示例plunkr吗