Step 61

Instruções

O último passo é deixar seu botão de limpar funcional. Adicione um ouvinte do evento de click para clearCartBtn. Para a função de callback, você pode passar cart.clearCart diretamente. No entanto, fazer isso não funcionará, pois o contexto de this será o elemento clearCartBtn. Você precisa vincular o método clearCart ao objeto cart. Você pode fazer isso passando cart.clearCart.bind(cart) como função de callback. E com isso, a oficina do carrinho de compras está completa!

O que fazer:

Testes:

Você deve adicionar um "ouvinte" de evento à variável `clearCartBtn`.
Seu listener de evento deve escutar o evento `click`.
O ouvinte de evento deve receber `cart.clearCart.bind(cart)` como função de callback.

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>G.E.A.R ACADEMY Shopping Cart</title>
    <link rel="stylesheet" href="./styles.css" />
  </head>
  <body>
    <header>
      <h1 class="title">Desserts Page</h1>
    </header>
    <main>
      <button id="cart-btn" type="button" class="btn">
        <span id="show-hide-cart">Show</span> Cart
      </button>
      <div id="cart-container">
        <button class="btn" id="clear-cart-btn">Clear Cart</button>
        <div id="products-container"></div>
        <p>Total number of items: <span id="total-items">0</span></p>
        <p>Subtotal: <span id="subtotal">$0</span></p>
        <p>Taxes: <span id="taxes">$0</span></p>
        <p>Total: <span id="total">$0</span></p>
      </div>
      <div id="dessert-card-container"></div>
    </main>
    <script src="./script.js"></script>
  </body>
</html>

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --dark-grey: #1b1b32;
  --light-grey: #f5f6f7;
  --black: #000;
  --white: #fff;
  --grey: #3b3b4f;
  --golden-yellow: #fecc4c;
  --yellow: #ffcc4c;
  --gold: #feac32;
  --orange: #ffac33;
  --dark-orange: #f89808;
}

body {
  background-color: var(--dark-grey);
}

.title {
  color: var(--light-grey);
  text-align: center;
  margin: 25px 0;
}

#dessert-card-container {
  display: flex;
  flex-direction: column;
  flex-wrap: wrap;
  align-items: center;
}

.dessert-card {
  background-color: var(--light-grey);
  padding: 15px;
  text-align: center;
  border-radius: 15px;
  margin: 20px 10px;
}

.dessert-price {
  font-size: 1.2rem;
}

.btn {
  display: block;
  cursor: pointer;
  width: 100px;
  color: var(--dark-grey);
  background-color: var(--gold);
  background-image: linear-gradient(var(--golden-yellow), var(--orange));
  border-color: var(--gold);
  border-width: 3px;
}

.btn:hover {
  background-image: linear-gradient(var(--yellow), var(--dark-orange));
}

#cart-btn {
  position: absolute;
  top: 0;
  right: 0;
}

.add-to-cart-btn {
  margin: 30px auto 10px;
}

#cart-container {
  display: none;
  position: absolute;
  top: 60px;
  right: 0;
  background-color: var(--light-grey);
  width: 200px;
  height: 400px;
  border: 8px double var(--black);
  border-radius: 15px;
  text-align: center;
  font-size: 1.2rem;
  overflow-y: scroll;
}

.product {
  margin: 25px 0;
}

.product-count {
  display: inline-block;
  margin-right: 10px;
}

.product-category {
  margin: 10px 0;
}

@media (min-width: 768px) {
  #dessert-card-container {
    flex-direction: row;
  }

  .dessert-card {
    flex: 1 0 21%;
  }

  #cart-container {
    width: 300px;
  }
}

const cartContainer = document.getElementById("cart-container");
const productsContainer = document.getElementById("products-container");
const dessertCards = document.getElementById("dessert-card-container");
const cartBtn = document.getElementById("cart-btn");
const clearCartBtn = document.getElementById("clear-cart-btn");
const totalNumberOfItems = document.getElementById("total-items");
const cartSubTotal = document.getElementById("subtotal");
const cartTaxes = document.getElementById("taxes");
const cartTotal = document.getElementById("total");
const showHideCartSpan = document.getElementById("show-hide-cart");
let isCartShowing = false;

class Dessert {
  constructor(id, name, price, category) {
    this.id = id;
    this.name = name;
    this.price = price;
    this.category = category;
  }
}

const products = [
  new Dessert(1, "Vanilla Cupcakes (6 Pack)", 12.99, "Cupcake"),
  new Dessert(2, "French Macaron", 3.99, "Macaron"),
  new Dessert(3, "Pumpkin Cupcake", 3.99, "Cupcake"),
  new Dessert(4, "Chocolate Cupcake", 5.99, "Cupcake"),
  new Dessert(5, "Chocolate Pretzels (4 Pack)", 10.99, "Pretzel"),
  new Dessert(6, "Strawberry Ice Cream", 2.99, "Ice Cream"),
  new Dessert(7, "Chocolate Macarons (4 Pack)", 9.99, "Macaron"),
  new Dessert(8, "Strawberry Pretzel", 4.99, "Pretzel"),
  new Dessert(9, "Butter Pecan Ice Cream", 2.99, "Ice Cream"),
  new Dessert(10, "Rocky Road Ice Cream", 2.99, "Ice Cream"),
  new Dessert(11, "Vanilla Macarons (5 Pack)", 11.99, "Macaron"),
  new Dessert(12, "Lemon Cupcakes (4 Pack)", 12.99, "Cupcake"),
];

products.forEach(
  ({ name, id, price, category }) => {
    dessertCards.innerHTML += `
      <div class="dessert-card">
        <h2>${name}</h2>
        <p class="dessert-price">$${price}</p>
        <p class="product-category">Category: ${category}</p>
        <button 
          id="${id}" 
          class="btn add-to-cart-btn">Add to cart
        </button>
      </div>
    `;
  }
);

class ShoppingCart {
  constructor() {
    this.items = [];
    this.total = 0;
    this.taxRate = 8.25;
  }

  addItem(id, products) {
    const product = products.find((item) => item.id === id);
    const { name, price } = product;
    this.items.push(product);

    const totalCountPerProduct = {};
    this.items.forEach((dessert) => {
      totalCountPerProduct[dessert.id] = (totalCountPerProduct[dessert.id] || 0) + 1;
    })

    const currentProductCount = totalCountPerProduct[product.id];
    const currentProductCountSpan = document.getElementById(`product-count-for-id${id}`);

    currentProductCount > 1 
      ? currentProductCountSpan.textContent = `${currentProductCount}x`
      : productsContainer.innerHTML += `
      <div id="dessert${id}" class="product">
        <p>
          <span class="product-count" id="product-count-for-id${id}"></span>${name}
        </p>
        <p>${price}</p>
      </div>
      `;
  }

  getCounts() {
    return this.items.length;
  }

  clearCart() {
    if (!this.items.length) {
      alert("Your shopping cart is already empty");
      return;
    }

    const isCartCleared = confirm(
      "Are you sure you want to clear all items from your shopping cart?"
    );

    if (isCartCleared) {
      this.items = [];
      this.total = 0;
      productsContainer.innerHTML = "";
      totalNumberOfItems.textContent = 0;
      cartSubTotal.textContent = 0;
      cartTaxes.textContent = 0;
      cartTotal.textContent = 0;
    }
  }

  calculateTaxes(amount) {
    return parseFloat(((this.taxRate / 100) * amount).toFixed(2));
  }

  calculateTotal() {
    const subTotal = this.items.reduce((total, item) => total + item.price, 0);
    const tax = this.calculateTaxes(subTotal);
    this.total = subTotal + tax;
    cartSubTotal.textContent = `$${subTotal.toFixed(2)}`;
    cartTaxes.textContent = `$${tax.toFixed(2)}`;
    cartTotal.textContent = `$${this.total.toFixed(2)}`;
    return this.total;
  }
};

const cart = new ShoppingCart();
const addToCartBtns = document.getElementsByClassName("add-to-cart-btn");

[...addToCartBtns].forEach(
  (btn) => {
    btn.addEventListener("click", (event) => {
      cart.addItem(Number(event.target.id), products);
      totalNumberOfItems.textContent = cart.getCounts();
      cart.calculateTotal();
    })
  }
);

cartBtn.addEventListener("click", () => {
  isCartShowing = !isCartShowing;
  showHideCartSpan.textContent = isCartShowing ? "Hide" : "Show";
  cartContainer.style.display = isCartShowing ? "block" : "none";
});

Preview