Using Render Callbacks in Angular Components

Is there a method to set up a callback that triggers every time the component is redrawn or re-rendered?

For example, can I track how many times the component has been updated on the DOM?

I have implemented OnPush change detection.

@Component({
  changeDetection: ChangeDetectionStrategy.OnPush,
  selector: 'app-my-component',
  templateUrl: './my-component.component.html',
  styleUrls: ['./my-component.component.scss']
})

My understanding is that when the inputs to the component are modified, it automatically triggers a redraw of the component, correct?

Answer №1

It seems like your understanding is on the right track, and it would be beneficial for you to utilize the ngOnChanges method.

As mentioned in the Angular documentation:

This method allows you to respond when Angular sets or resets data-bound input properties. You will receive a SimpleChanges object containing both the current and previous values of the properties. Keep in mind that this process occurs frequently, so any operations within this method can have a significant impact on performance. For more information, refer to the section on Using change detection hooks in the documentation.

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