title: How do I know when custom form control is marked as pristine in Angular?
body: <p>I have several custom form control components in my Angular application, which implement <code>ControlValueAccessor</code> interface and it works great.</p>
  
  <p>However, when <code>markAsPristine()</code> is called on parent form, or on my custom control directly I need to update it's state: my custom control is actually have internal control and I need to call <code>markAsPristine()</code> on it too.</p>
  
  <p><strong>SO, how do I know when <code>markAsPristine()</code> is called on my control?</strong></p>
  
  <p>The <code>ControlValueAccessor</code> interface has no members, related to this problem, which I can implement.</p>