Window:scroll event does not work in my Ionic app

If I use the following code in an Ionic app it does not work, but the exact same code works perfectly in a plain ng app. Is there a way to work around this?

import { Component, HostListener, Inject, OnInit } from "@angular/core";
import { DOCUMENT } from '@angular/platform-browser';

import { NavController } from 'ionic-angular';

@Component({
  selector: 'page-home',
  templateUrl: 'home.html'
})
export class HomePage implements OnInit {

  constructor(public navCtrl: NavController,
    @Inject(DOCUMENT) private document: Document) { }

    ngOnInit() { }

    @HostListener("window:scroll", [])
    onWindowScroll() {
      let number = this.document.body.scrollTop;
      console.log('scrolling: ', number);
    }    
}

It worked out by using Content instead of Document .

import {ViewChild } from '@angular/core';
import { Content } from 'ionic-angular';

-----//-----

export class SamplePage {
  @ViewChild(Content) content: Content;

  constructor( ) {
  }

  ionViewDidEnter() {
    console.log(this.content); // => Content {_config: Config, …}
    this.content.scrollToBottom(); // => ScrollDown
  }
}

This link might be also helpful.