Remove duplicate attribute(ngModel, value) in angu

Question

I have made a DatePickerDirective which is working fine as required. But in order to sync the value of the particular input field on which this directive sits, I have to use value and ngModel attribute both. I wish to use only ngModel how can this be achieved gracefully.

Form Element

 <input appDatePicker type="text" required name="title" value="{{holiday.off_date}}" [(ngModel)]="holiday.off_date" class="form-control"
                       placeholder="01/01/2018">

Component File

export class HolidayCreateComponent implements OnInit, OnDestroy {

  holiday = new HolidayModel('', '');

}

Model File

export class HolidayModel {

  constructor(public occasion: string, public off_date: string) {
  }

}

Directive File

import {Directive, ElementRef, forwardRef, OnInit} from '@angular/core';
import {ControlValueAccessor, NG_VALUE_ACCESSOR} from '@angular/forms';

declare const $: any;

@Directive({
  selector: '[appDatePicker]',
  providers: [{
    provide: NG_VALUE_ACCESSOR, useExisting:
      forwardRef(() => DatePickerDirective),
    multi: true
  }]
})
export class DatePickerDirective implements OnInit, ControlValueAccessor {

  value: string;

  constructor(private el: ElementRef) {

  }


  ngOnInit() {
    $(this.el.nativeElement).datepicker({
      autoclose: true,
      todayHighlight: true,
      format: 'dd/mm/yyyy'
    }).on('change', e => this._onChange(e.target.value));
  }


  private _onChange(_) {
  }

  private _onTouched(_) {
  }

  registerOnChange(fn: any): void {
    this._onChange = fn;
  }

  registerOnTouched(fn: any): void {
    this._onTouched = fn;
  }

  setDisabledState(isDisabled: boolean): void {
  }

  writeValue(val: string): void {
    this.value = val;
  }


}

The problem is whenever i try to manipulate value of date field from component i need use both value and ngmodel. I think this is not right can be improved. Is there anything which i forgot.

NOTE: the value and ngModel is required only where directive is used. If the input has no directive then ngModel works just perfect. I want the same behavior for the element with directive.

Answer 1

value simply means the initial, default value of the datepicker. ngModel is the two-way bound object that has your data afther the user pick's the date. Your code is fine as it is.