Reputation: 1834
I've got a dynamic array which I want to render in the view of a component when some items added / removed inside.
The array is rendered by ngOnInit()
method in my App Component (ts):
import { Component, OnInit } from '@angular/core';
import { CartService } from './cart/cart.service';
import '../style/app.scss';
@Component({
selector: 'my-app',
templateUrl: './app.component.html',
styleUrls: ['./app.component.scss'],
})
export class AppComponent {
cartItems: any;
image: any;
item: any;
constructor(public cartService: CartService) { }
ngOnInit(){
this.cartService.cart$.subscribe((val) => {
console.log(this.cartService.cartArr)//console shows the array properly, but nothing is shown in the view if I remove "console.log"
});
}
}
"The view" for the array inside my App Component (html):
<ul class="cart">
<li class="cart__item" *ngFor="let item of cartArr">
...
</li>
</ul>
My CartService:
import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
@Injectable()
export class CartService {
public cart$ = new BehaviorSubject(null);
public cartArr = [];
constructor(){ }
public addToCart(prod) {
this.cartArr.push(prod);
this.cart$.next(this.cartArr);
}
}
So I wonder how to render the array in the Component html and why my code isn't working outside the console?
Upvotes: 1
Views: 1298
Reputation: 214047
Update:
As said @TuongLe in comment if you manually subscribe to your observable then you should to call unsubscribe
in ngOnDestroy
to prevent memory leak.
You can either
1) set array value:
cartItems: any[];
cartSubscription: Subscription;
ngOnInit() {
this.cartSubscription = this.cartService.cart$.subscribe((val) => {
this.cartItems = val;
});
}
ngOnDestroy() {
this.cartSubscription.unsubscribe();
}
view
*ngFor="let item of cartItems"
or
2) use async
pipe like:
*ngFor="let item of cartService.cart$ | async"
Upvotes: 3