angular 2 fullcalendar,refetchEvents not working(full calendar is not a function error)

I am using angular 2 fullcalendar for one of my projects.everything works fine as long as i have the data ready before rendering the calender.If an event is triggered and data comes from backend,i am facing problem while using refetch function.I wil explain the code first and describe the error. I have installed

npm install fullcalendar

npm i angular2-fullcalendar

npm install jquery

npm install moment

in app.module.ts

i have imported

import {CalendarComponent} from "angular2-fullcalendar/src/calendar/calendar";

and i have declared in the declaration:[]

in html i am displaying calendar using

<div class="ui red segment" *ngIf="dataAvailable">
<angular2-fullcalendar [options]="calOptions" id="mycal" #mycal>
</angular2-fullcalendar>
</div>

In the component i have

import {CalendarComponent} from 'angular2-fullcalendar/src/calendar/calendar';
import {Options} from 'fullcalendar';

declare var $:any;
import * as moment from "moment";

and i have a refference to the tag like

 @ViewChild('mycal', { read: ElementRef }) myCal: ElementRef;

and my calendar configuration looks like

 calOptions: any = {
        height:350,
        defaultDate: moment(new Date(),'YYYY-MM-DD'),
        editable: false,
        stick:true,
        
        events:this.events,
        selectable:false,
        eventLimit: true, // allow "more" link when too many events
        header: {
                  left: 'month basicWeek basicDay',
                  center: 'title',
                  right: 'today prev,next'
                },
        displayEventTime: false,
        addEventSource:this.events,
        defaultView:'basicWeek',
       
        dayRender: (date, cell)=> {
                        var today = moment().format("YYYY-MM-DD");
                    //    today = moment(today).toDate();
                        
                        for(let item of this.holidayList){
                        
                        if(item.holidayDate === moment(date).format("YYYY-MM-DD"))
                        {
                         cell.css("background-color", "#e4564a");
                         
                        }
                        }
          } 
  };

Problem

Now when the new data comes if i try

$(this.myCal.nativeElement).fullCalendar('addEventSource', events)

It gives an error saying

Cannot read property 'nativeElement' of undefined

and if i try using

$('#mycal').fullCalendar('refetchEventSources',this.events);

it gives the error

caused by: $(...).fullCalendar is not a function

also if i use

$('angular2-fullcalendar').fullCalendar('refetchEventSources',this.events);

same error comes.What am i doing wrong??Please help.I am really stuck;

update

i did i did

@ViewChildren('mycal') cal: QueryList<CalendarComponent>

and after the new data comes,in the subscribe method i did,

this.cal.forEach(div => 
  {
    div.fullCalendar('removeEventSource', this.events);
     div.fullCalendar('addEventSource', this.events);
      div.fullCalendar('refetchEvents');

  }

Now it when the new data comes,old data is not removed from the view,but it is getting appended with the existing view.

That's because you are using an *ngIf, your element might be present or not.

Instead of using @ViewChild('mycal') You should consider using @ViewChildren('myCal') and subscribe to QueryList.changes Observable:

@ViewChildren('myCal')
cal: QueryList < ElementRef > ;

ngAfterViewInit() {
  this.cal.changes
    .startWith(this.cal)
    .filter(list => list.length > 0)
    .subscribe(list => {
      console.log(list.first);
    })
}