app.component.ts

import { Component, OnInit } from '@angular/core';
import { Observable } from 'rxjs';
import * as fromRoot from './reducers/';
import { Increment, Decrement, Reset } from './actions/counter.actions';
import { StoreService, select } from './store.service';

@Component({
  selector: 'my-app',
  templateUrl: './app.component.html',
})
export class AppComponent implements OnInit {
  counter: Observable<number>;

  constructor(
    private storeService: StoreService
  ) { }

  ngOnInit() {
    this.counter = this.storeService.getState().pipe(select(fromRoot.getCount));
  }

  increment() {
    this.storeService.dispatch(new Increment());
  }

  decrement() {
    this.storeService.dispatch(new Decrement());
  }

  reset() {
    this.storeService.dispatch(new Reset());
  }
}