InputSwitch not firing change detection on external value change with Push Strategy

[meeroslav]

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Plunkr Case (Bug Reports)
https://stackblitz.com/edit/github-kxjjv5?file=src%2Fapp%2Fapp.component.ts

Current behavior
The writeValue method does not fire change detection.
When using ChangeDetectionStrategy.OnPush value gets set later and change doesn't propagate.

Expected behavior
The component should work same with and without the OnPush change detection strategy.

Minimal reproduction of the problem with instructions
When you disable ChangeDetectionStrategy.OnPush it works, but with change detection on UI doesn't refresh, because writeValue doesn't trigger the change event.

What is the motivation/use case for changing the behavior?
InputSwitch used within components with OnPush strategy do not get value properly initialized. This is because the method writeValue is called after the component has been drawn and initialized, and change is never propagated.

Please tell us about your environment:
Linux Ubuntu, Yarn, Webstorm

• Angular version: 5.X
  6.1.1

• PrimeNG version: 5.X
  6.1.3

• Browser: all

• Language: all

[cagataycivici]

Here is an example that will work with upcoming 6.1.4

<p-inputSwitch [(ngModel)]="checked"></p-inputSwitch>

import {Component,ChangeDetectionStrategy,ChangeDetectorRef} from '@angular/core';

@Component({
    templateUrl: './inputswitchdemo.html',
    changeDetection: ChangeDetectionStrategy.OnPush
})
export class InputSwitchDemo {

    checked: boolean = false;

     constructor(private cd: ChangeDetectorRef) {}

    ngOnInit() {
        setTimeout(() => {
            this.checked = true;
            this.cd.markForCheck();
        }, 2000);
    }
}