laravel中的购物车，将产品添加到购物车时出错

Question

I am creating Shopping cart. While i try to add products to cart, it shows error.

My code and errors are as follows.

Indirect modification of overloaded property App\\cart::$item has no effect in cart.php (line 31)

productcontroller.php contains the following code:

public function getAddToCart(Request $request, $id){
 $product = Products::findOrFail($id);
 $oldCart = Session::has('cart') ? Session::get('cart') : null;
 $cart = new cart($oldCart);
 $cart->add($product, $product->id);

 $request->session()->put('cart', $cart);
 return redirect('jewellery/items');
}

In cart.php contains the following code:

public function add($item, $id){
  $storedItem = ['qty' => 0, 'price' => $item->net_total, 'item' => $item ];
  if($this->items){
   if(array_key_exists($id, $this->items)){
    $storedItem = $this->items[$id];
   }
  }
  $storedItem['qty']++;
  $storedItem['price'] = $item->net_total * $storedItem['qty']; 
  $this->item[$id] = $storedItem;
  $this->totalQty++;
  $this->totalPrice += $item->price;
 }

Please help me to clear this.

Thanks in advance.

Answer 1

Have you added __construct() method in your cart model? If not then add it to the and also set items object and give total quantity and price 0. here is the code :

public $items;
public $totalQty = 0;
public $totalPrice = 0;

public function __construct($oldCart)
{
    if ($oldCart) {
      $this->items = $oldCart->items;
      $this->totalQty = $oldCart->totalQty;
      $this->totalPrice = $oldCart->totalPrice;
    }
}