What is the reason for the array length view not updating when a new object is added?

I am dealing with an array of objects and the length is displayed using this code snippet:

<strong *ngIf="cart">{{ cart.length }}</strong>

Even though when I add items to the array, both the array and its length are showing correctly in the console, the view does not update and still shows 0. Here is a snippet from my .ts file:

cart=[];
add = (item) => {
  this.cart.push(item);
  console.log(this.cart);
  console.log(this.cart.length);
}

Your assistance on this issue would be greatly appreciated!

Answer №1

Adding an item to an array:

this.cart.push(item);

Will not trigger a re-render because the cart array reference is not updated.

To update your view properly, try adding elements like this:

this.cart = [...this.cart, newItem];

This way, your view should be updated correctly.

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