datectChanges

datectChanges.ts

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

@Component({
  template: `...`,
  changeDetection: ChangeDetectionStrategy.OnPush
})
export class CounterComponent {
  count = 0;

  constructor(private cd: ChangeDetectorRef) {
    setTimeout(() => {
      this.count++
      this.cd.detectChanges()
    }, 0);

    this.http.get('https://count.com').subscribe(res => {
      this.count = res;
      this.cd.detectChanges()
    });
  }
}