Bootstrap NgbDate Date Range Calendar - "TypeError: Cannot read property 'equals' of undefined"

Question

I'm using Angular Bootstrap to create a date range picker and although the code is exactly what's in their example, I get several errors, all stating "TypeError: Cannot read property 'equals' of undefined".

This is the code I have: https://stackblitz.com/angular/ggxrvppdjeq

The only real difference is that I'm importing NgbDate from another folder: import { NgbDate } from '@ng-bootstrap/ng-bootstrap/datepicker/ngb-date';

If I try to do it from @ng-bootstrap/ng-bootstrap as the example had, I get an error in VSCode: node_modules/@ng-bootstrap/ng-bootstrap"' has no exported member. Switching it to what I have above makes the error go away... but perhaps this is causing the issue?

Template:

<ngb-datepicker #dp (select)="onDateSelection($event)" [displayMonths]="2" [dayTemplate]="t" outsideDays="hidden">
</ngb-datepicker>

<ng-template #t let-date let-focused="focused">
  <span class="custom-day"
        [class.focused]="focused"
        [class.range]="isRange(date)"
        [class.faded]="isHovered(date) || isInside(date)"
        (mouseenter)="hoveredDate = date"
        (mouseleave)="hoveredDate = null">
    {{ date.day }}
  </span>
</ng-template>

<hr>

<pre>From: {{ fromDate | json }} </pre>
<pre>To: {{ toDate | json }} </pre>

Component:

import { Component, OnInit } from '@angular/core';
import { NgbCalendar } from '@ng-bootstrap/ng-bootstrap';
import { NgbDate } from '@ng-bootstrap/ng-bootstrap/datepicker/ngb-date';

@Component({
  selector: 'ngbd-datepicker-range',
  templateUrl: './datepicker-range.html',
  styles: [`
    .custom-day {
      text-align: center;
      padding: 0.185rem 0.25rem;
      display: inline-block;
      height: 2rem;
      width: 2rem;
    }
    .custom-day.focused {
      background-color: #e6e6e6;
    }
    .custom-day.range, .custom-day:hover {
      background-color: rgb(2, 117, 216);
      color: white;
    }
    .custom-day.faded {
      background-color: rgba(2, 117, 216, 0.5);
    }
  `]
})
export class NgbdDatepickerRange {

  hoveredDate: NgbDate;

  fromDate: NgbDate;
  toDate: NgbDate;

  constructor(calendar: NgbCalendar) {
    this.fromDate = calendar.getToday();
    this.toDate = calendar.getNext(calendar.getToday(), 'd', 10);
  }

  onDateSelection(date: NgbDate) {
    if (!this.fromDate && !this.toDate) {
      this.fromDate = date;
    } else if (this.fromDate && !this.toDate && date.after(this.fromDate)) {
      this.toDate = date;
    } else {
      this.toDate = null;
      this.fromDate = date;
    }
  }

  isHovered(date: NgbDate) {
    return this.fromDate && !this.toDate && this.hoveredDate && date.after(this.fromDate) && date.before(this.hoveredDate);
  }

  isInside(date: NgbDate) {
    return date.after(this.fromDate) && date.before(this.toDate);
  }

  isRange(date: NgbDate) {
    return date.equals(this.fromDate) || date.equals(this.toDate) || this.isInside(date) || this.isHovered(date);
  }
}

I was able to implement this successfully in an outside project but when I inserted into this existing project I'm having issues. Any help would be much appreciated, I can't figure it out.

Answer 1

This is just a typo issue on their official documentation. In ng-template, date is not passed as input that's why it is producing undefined error.

<ng-template #t let-date let-focused="focused">

Change this to

<ng-template #t let-date="date" let-focused="focused">