useReducer with useContext Part 3
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Connect the context and reducer with the frontend
React Hooks Handbook
1
Intro to React Hooks
3:39
2
Create your first React app
4:23
3
React Component
2:54
4
Styling in React
5:06
5
Styles and Props
2:22
6
Understanding Hooks
3:21
7
useState Hook
2:54
8
useEffect Hook
3:41
9
useRef Hook
3:00
10
Props
3:11
11
Conditional Rendering
4:21
12
Load Local Data
4:04
13
Fetch Data from an API
5:40
14
Toggle a state
4:05
15
useInput Hook
6:04
16
Gatsby and React
6:44
17
NextJS and React
5:24
18
React TypeScript Part 1
8:19
19
React TypeScript Part 2
7:35
20
useScrollPosition Hook
4:26
21
useOnScreen hook
8:08
22
useContext Hook
8:32
23
Fragments
2:43
24
Lazy Loading
4:05
25
React Suspense
3:13
26
Environment Variables
4:43
27
Reach Router
5:31
28
URL Params
4:04
29
SEO and Metadata
6:47
30
Favicon
3:03
31
Dynamic Favicon
2:14
32
PropTypes
3:54
33
Custom PropTypes
3:58
34
useMemo Hook
4:05
35
forwardRef Hook
3:28
36
Handling Events
5:44
37
Spread attributes
3:35
38
useMousePosition Hook
4:55
39
useReducer with useContext Part 1
7:33
40
useReducer with useContext Part 2
6:48
41
useReducer with useContext Part 3
5:43
42
Netlify
5:08
43
Gatsby Cloud
6:19
44
Gatsby Plugin Image
8:11
45
useOnClickOutside Hook
6:32
46
useWindowSize Hook
4:14
47
usePageBottom hook
4:48
48
useLocalStorage Hook
5:27
49
Three.js in React Part 1
17:33
50
Three.js in React Part 2
11:18
CodeSandbox Links
If you haven't, I highly encourage you to follow the first part , the second part of this tutorial, and fork the starter project for this tutorial. You can also access the complete code of this tutorial, with styling, at https://codesandbox.io/s/usereducer-hook-swkwl.
Add and remove product from cart
We'll use the useShop hook in our ProductCard component. Let's import it in ProductCard.js.
// ProductCard.js
import useShop from "./ShopContext";Inside of the ProductCard component, we'll access the products array and the addToCart and removeFromCart functions.
// ProductCard.js
const { products, addToCart, removeFromCart } = useShop();Now, we need to determine if the product is already in the cart. For the purposes of this tutorial, the user will only be able to add the product to their cart once. If it's already in their cart, we'll remove the product from their cart. Import useState and useEffect.
// ProductCard.js
import { useState, useEffect } from "react";Define a state called isInCart , which will be a boolean. It'll be false by default.
// ProductCard.js
const [isInCart, setIsInCart] = useState(false);Create a useEffect . Inside of it, we'll take the products array from the useShop context, and try to find the product by its name . If we found a product in the products array, we'll set it to true , if not, we'll set it to false.
// ProductCard.js
useEffect(() => {
const productIsInCart = products.find((product) => product.name === name);
if (productIsInCart) {
setIsInCart(true);
} else {
setIsInCart(false);
}
}, [products, name]);Let's update the UI for the AddButton , by passing the isInCart prop to it. If the product is already in the cart, the button will be red and a minus sign will be displayed. Otherwise, the button will be green and a plus sign will be displayed.
// ProductCard.js
<AddButton isInCart={isInCart} onClick={() => console.log(`Added ${name} to cart`)}>
<p>{isInCart ? "-" : "+"}</p>
</AddButton>// ProductCard.js, styling
const AddButton = styled.div`
background: ${(props) => (props.isInCart ? "#E55336" : "#60c95d")};
`Next, let's create a handleClick function that handles the onClick event. If the product is already in the cart, we'll remove it. Otherwise, we'll add it to the cart.
// ProductCard.js
const handleClick = () => {
const product = { name, imageUrl, price };
if (isInCart) {
removeFromCart(product);
} else {
addToCart(product);
}
};Now, test out the code! Every time we click on the add button, it should turn red with a minus sign. If we click again, the button should become green with a plus sign. Also, console log the products array from the context to make sure that the array is updated accordingly.
Cart page
Now that the Home page has been taken care of, let's move on to the Cart page. Here, we want to display all the products in the user's cart. We also want to show the total price of their cart. First, import useShop in Cart.js.
// Cart.js
import useShop from "./ShopContext";We'll need the products array from useShop.
// Cart.js
const { products } = useShop();Let's display the products in their cart first, so we'll map through the products array. For each product, we'll display a product card. Remember to also import the ProductCard in Cart.js.
// Cart.js
import ProductCard from "./ProductCard";
// More content...
<div>
{products.map((product, index) => (
<ProductCard {...product} key={index} />
))}
</div>Now, we want to display the total amount of their cart. Let's extract the total variable from useShop.
// Cart.js
const { products, total } = useShop();And simply call it in our text!
<h2>Your cart total is {total}.00$</h2>Great! We completed our online shopping website! Your final cart page should look like this, when you add a few items to your cart. The total amount should be updated, and all products you added to your cart should be displayed on a product card.
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1
Intro to React Hooks
An overview of React Hooks and the frameworks you can use to build your React application blazingly fast
3:39
2
Create your first React app
Create your first React project from the Terminal and save it on your local computer
4:23
3
React Component
Create your first JSX component using React
2:54
4
Styling in React
How to style your React components using inline styling, separate stylesheets or styled-components
5:06
5
Styles and Props
Render different styles depending on different properties passed to your component
2:22
6
Understanding Hooks
Learn about the basics of React Hooks, which introduced at React Conf 2018
3:21
7
useState Hook
Use the useState hook to manage local state in your React component
2:54
8
useEffect Hook
Manage with your component's lifecycle with the useEffect hook
3:41
9
useRef Hook
Learn about the useRef hook, which replaces the JavaScript getElementById way
3:00
10
Props
Learn about props in React to pass data from parent to child components
3:11
11
Conditional Rendering
Render different UIs depending on different conditions and states
4:21
12
Load Local Data
Load local JSON data into your React application
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13
Fetch Data from an API
Learn the basics of asynchronous functions and promises by fetching data from an API using fetch, useEffect and useState
5:40
14
Toggle a state
Learn how to toggle a state from true to false and back again
4:05
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useInput Hook
Create a hook to get the value and the onChange event of input fields
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16
Gatsby and React
Create a static content-oriented website using React on Gatsby
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17
NextJS and React
Create your first NextJS React application
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React TypeScript Part 1
Learn how to create a React TypeScript application using the Create React App, Gatsby and NextJS methods
8:19
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React TypeScript Part 2
Learn the basics of TypeScript and how to use TypeScript in a React component
7:35
20
useScrollPosition Hook
Create a custom hook to listen to the current window position of the user
4:26
21
useOnScreen hook
Create a custom hook to listen to when an element is visible on screen
8:08
22
useContext Hook
Manage global states throughout the entire application
8:32
23
Fragments
Group multiple children together with React Fragments
2:43
24
Lazy Loading
Lazy Load heavy components to improve performance
4:05
25
React Suspense
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3:13
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Environment Variables
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Reach Router
Create a multiple-pages React application with Reach Router
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URL Params
Create unique URL with URL Params
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SEO and Metadata
Optimize a React application for search engines with React Helmet
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30
Favicon
Add an icon to a React website
3:03
31
Dynamic Favicon
Change the favicon's fill color depending on the user's system appearance
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32
PropTypes
Implement props type-checking with PropTypes
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33
Custom PropTypes
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34
useMemo Hook
Prevent unnecessary re-renders when the component stays the same
4:05
35
forwardRef Hook
Forward a ref to a child component
3:28
36
Handling Events
How to handle events in React
5:44
37
Spread attributes
Learn how to make use of the spread operator
3:35
38
useMousePosition Hook
Detect the user's mouse position on a bound element
4:55
39
useReducer with useContext Part 1
Create a reducer to be used in a context
7:33
40
useReducer with useContext Part 2
Incorporate useReducer with useContext
6:48
41
useReducer with useContext Part 3
Connect the context and reducer with the frontend
5:43
42
Netlify
Deploy to production using Netlify
5:08
43
Gatsby Cloud
Deploy to production using Gatsby Cloud
6:19
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Gatsby Plugin Image
Use gatsby-plugin-image for automatic image resizing, formatting, and higher performance
8:11
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useOnClickOutside Hook
Toggle a modal visibility with a useOnClickOutside hook
6:32
46
useWindowSize Hook
Create a hook to determine the width and height of the window
4:14
47
usePageBottom hook
Detect if the user scrolled to the bottom of the page
4:48
48
useLocalStorage Hook
Store an item in a browser's local storage
5:27
49
Three.js in React Part 1
Bring your website to life with beautiful 3D objects
17:33
50
Three.js in React Part 2
Bring your website to life with beautiful 3D objects
11:18
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