The Power of Hooks in React: Dynamic Applications Made Simple

A recent addition to the React library, Hooks, has fundamentally changed the way developers create React components. Without the need to create a class component, hooks allow functional components to access other React resources and have state.

Before Hooks, class components were the only option for adding state to a React component. However, as the complexity of the React component increased, the class components became time-consuming and difficult to understand. Developers can manage state and other logic in a functional component using hooks, which makes their code shorter and simpler to understand.

Hooks have quickly become an integral part of the React community, offering intuitive and efficient ways to manage component logic and making code easier to understand and execute. It revolutionized the way React components are written.

This article will cover the basics and advanced concepts of hooks so that you can understand how to use them to create robust, scalable, and flexible applications. By the end of this article, you will have a good understanding of hooks and will be able to use them in your own projects.

What are hooks?

Functional components can now handle state and perform side effects that were previously only available in class components, thanks to React Hooks. Developers can build cleaner, more reusable code with hooks, which makes the codebase simpler to understand and maintain.

Hooks in React allow you to efficiently bring state and other functionality to your functional components by providing them with the functionality of class components.

There are two types of hooks; state hooks and effect hooks . The table below presents a brief comparison between the two.

With the help of hooks, the application and code become efficient, reusable and easier to understand. Additionally, components can share hooks, making it simple to share their state and other functionality across applications.

Why should you use hooks in React?

React Hooks transform your functional components to deliver unparalleled flexibility, simplified state management, and efficient code. Let's take a look at how these hooks can help you in the app development process.

1. Hooks help make your code easier to understand and increase readability by effectively embedding state and other functionality into functional components. As a result, it allows you to create easily readable and modified code.
2. Hooks improve the reusability of code by sharing it between components, making it simpler to efficiently share your state and additional functionality between your applications. It helps to reduce the code and make it reusable.
3. Hooks improve application performance by optimizing it with the help of useMemo hooks that help in memorizing calculations. Helps improve application performance.
4. Hooks improve the developer experience by simplifying component functionality while minimizing the number of class components. It increases productivity and efficiency and gives more satisfactory results.

We will now look at an example to familiarize you with using hooks. This example demonstrates the useCallback hook.

 import React, { useState, useCallback } from 'react';

 function UseCallbackExample {
 const (increment, setIncrement) = useState(0);
 const val = useCallback( => {
  setIncrement(counterIncrement => counterIncrement + 1);
 }, (setIncrement));
 return (
  < div >
   < p >You have clicked {increment} times.</ p >
   < button onClick={val}>
    Click Here!
   </ button >
  </ div >
 );
 }

 export default UseCallbackExample;

The memorized function created in the example above uses the useCallback hook. To avoid recalculating a value, think of memoization as caching it. This allows us to separate resource-intensive operations so that they don't start automatically on every render. The function is modified when specific dependencies change, improving performance and avoiding unnecessary re-rendering of components.

Overall, hooks simplify code, improving performance, developer experience, and reusability. Additionally, hooks have modified developer approaches to writing and executing code, providing flexibility and more organized approaches, making it an essential tool.

How can you use hooks in React?

Various types of hooks in React allow developers to build their applications easily and efficiently. This section will delve into six commonly used hooks. State and effect hooks are the most commonly used in React.

State hooks allow adding and updating state to functional components. Developer can use State hooks by importing useState hooks from React library. After importing the useState hook, we will call it inside our component, passing an initial state value, providing an array as output. An array will contain two components: the current state value and the setter function to modify the state.

Effect hooks allow developers to execute side effects within functional components by getting the data with the help of an API or modifying the document title. Developer can use effect hooks by importing useEffect hooks from React library. After importing the useEffect hook, we will call it inside our component and provide a function that defines the effect. Every subsequent rendering of the component will call this function. Developers can use as many hooks as they want in the same component, allowing them to bring in multiple states and perform multiple side effects.

To use Hooks efficiently, it's crucial to follow a few guidelines:

• We cannot use hooks in class components as they are mainly made for functional components.
• Hooks should not be called inside loops, conditions, or nested functions , as this may result in unexpected behavior. When you avoid this, hooks are called in the same order every time a component is rendered. Instead, hooks are best used at the top level of a component, and conditionals can use the returned values.

These guidelines will help you use hooks effectively and maintain the functionality and efficiency of your application. Additionally, it's crucial to keep in mind that hooks will only work on React function components; As a result, when you need to include side or state effects in a class component, use class-based components or consider converting them to function components.

Hooks are an essential tool that allows developers to create an effective and dynamic application, making it efficient, reusable and easy to understand. This section will explore the types of hooks and provide examples of their implementation. Following are the types of hooks in React.

1. useState

The useState hook allows developers to add and modify functional components by managing state within components. The useState hook returns a current state and the function that modifies the state.

State includes objects and arrays as one of the state types. useState hooks optimize state management within the functional component and improve application performance by providing effective approaches to handling state. Let's look at an example to better understand the useState hook.

Start by importing the useState hook from the React library, and then we will call it inside the component passing an initial value of 0. Now use an increment variable that is initialized to 0. The current state value would be increment, and the colonizing function is setIncrement.

When you click the Click Me button, the state is modified with the setIncrement colonizer function, and the increment of the current state value is used to display how many times you have performed the clicks. Once the button is clicked, the state value will be saved and the component will be re-rendered to the setIncrement settler function to update it with a new value.

 import React, { useState } from 'react';

 function UseStateExample {
 // Declare the useState variable "increment"
 // After declaring the variable, initialize it to 0
 const (increment, setIncrement) = useState(0);

 return (
  < div >
   < h4 >You have performed {increment} clicks.</ h4 > 
< button onClick={ => setIncrement(increment + 1)}>
 Click Me
 </ button >
 </ div >
 );
 }

 export default UseStateExample;

We saw how a value increases every time we click a button using useState hooks. useState hooks are simple and essential for handling state in React function components. It helps modify and add state, providing efficiency to the code and making it easier to understand.

2. useEffect

The useEffect hook allows developers to perform side effects on functional components by fetching the data with the help of an API or modifying the document title.

Let's explore an example for a better understanding of the useEffect hook.

Start by importing the useEffect hook from the React library. After importing the useEffect hook, we will call it inside the component by passing a function that defines the useEffect.

In our case, we are modifying the title of the document to return the display of how many times we clicked. The useEffect hook runs after each component renders, consisting of the initial and subsequent re-renders.

Thus, the increment was updated by rerendering the component that executed that useEffect that modified the document title.

 import React, { useState, useEffect } from 'react';

 function UseEffectExample {
 // Declare the usestate variable "increment"
 // After declaring the variable, initialize it to 0
 const (increment, setIncrement) = useState(0);

 // Declare a useEffect hook which executes after each render
 useEffect( => {
  document.title = `You have performed ${increment} clicks`;
 });

 return (
  < div >
   < h4 >You have performed {increment} clicks.</ h4 >
   < button onClick={ => setIncrement(increment + 1)}>
    Click Me
   </ button > 
</ div >
 );
 }

 export default UseEffectExample;

useEffect is an essential tool for managing side effects within the React function component. useEffect helps improve code performance, maintainability, and understandability.

3. useContext

Another commonly used hook is the useContext hook, which allows us to access context data within functional components. In React, useContext is a technique to send the data with the help of a component tree without manually sending the props at each stage.

Let's see an example for a better understanding of the useContext hook.

Use useContext to initialize the context and call the React.createContext method, which takes the initial value as an input parameter. We are using a yellow background and a white color as the initial value.

 import React, { useContext } from 'react';

 // Create a useContext hook
 const UseContextTheme = React.createContext({
 background: 'yellow',
 color: 'white'
 });

The UseContextThemeButton component uses the context by calling the useContext hook with the context as a parameter. It will return the current context value, blue background and white color property.

 // This components utilized the context
 function UseContextThemeButton {
 const themeButton = useContext(UseContextTheme);

 return (
  < button style= {{ background: themeButton.background, color: themeButton.color }} >
   I am a Use Context Theme Button
  </ button >
 );
 }

Now we use the UseContextThemeProvider component to wrap its children in UseContextTheme.Provider, giving the prop value a context value.

 // This components provides the context
 function UseContextThemeProvider({ children }) {
 return (
  < UseContextTheme.Provider value= {{ background: 'blue', color: 'white' }} >
   {children}
  </ UseContextTheme.Provider >
 );
 }

Now we combine the above functions into one so that we can call it as a component in itself.

 // Function that calls all of the above functions
 function UseContextExample {
 return (
  <UseContextThemeProvider>
   < UseContextTheme_Button />
  </ UseContextThemeProvider >
 );
 }

 export default UseContextExample;

A useContext hook is an essential tool for accessing context data in the React functional component. Additionally, it helps optimize code performance by avoiding re-rendering whenever the context value changes.

4. use Reducer

The useReducer hook is an essential tool that allows us to handle the complex state logic within the functional component. It is analogous to the useState hook. However, it offers more flexibility in determining how the state was updated.

The following code demonstrates an example of the useReducer hook.

Start by creating a function called incrementDecrement that takes two parameters: state and action. The modification of the state is described by the action, which is an object. In our case, adding and subtracting are two actions that increase and decrease the value.

 import React, { useReducer } from 'react';

 // Declare the incrementDecrement function
 function incrementDecrement(state, action) {
 switch (action.type) {
  case 'subtract':
   return { value: state.value - 1 };
  case 'add':
   return { value: state.value + 1 };
  default:
   throw new Error;
 }
 }

The incrementDecrementCounter function uses the useReducer hook, which takes the incrementDecrement function and the initial state as an argument. First, the initial state is declared as a value initialized to 0. Then the useReducer hook returns the dispatch function and the current state as output.

The dispatch function uses the dispatch action, which results in the modification of the state. Then render the plus and minus buttons along with the value.

 function incrementDecrementCounter {
 const (state, dispatch) = useReducer(incrementDecrement, { value: 0 });
 return (
  <>
  < h3 >
   Value: {state.value}
  </ h3 >
   <p> </p>
   < button onClick={ => dispatch({ type: 'add' })}>+</ button >
   < button onClick={ => dispatch({ type: 'subtract' })}>-</ button >
  </>
 );
 }

 export default incrementDecrementCounter;

Clicking the add button will increase the value by one, while clicking the subtract button will decrease the value by one.

In React, the useReducer hook is useful because it prevents unnecessary re-renders and helps maintain code.

5. useMemo

The useMemo hook allows us to optimize by memorizing the values ​​and avoiding unnecessary re-rendering of components. It requires a dependency array and a function as a parameter. The function returns the value that should be memorized, while a memorized value lists the dependencies in the dependency array. Furthermore, the memorized value is recalculated whenever the value is changed.

The following code demonstrates an example of the useMemo hook.

The UseMemoExample component uses the first name, middle name, and last name as a bracket that uses the useMemo hook to hold the value.

The UseMemoApp component handles the state of the first, middle and last fields. These fields store a person's name after text is entered. The state will be updated every time the value is modified in the input text with the help of onChange event.

 import React, { useState, useMemo } from 'react';

 const UseMemoExample = ({ first, middle, last }) => {
 const Name = useMemo( => { 
return `${first} ${middle} ${last}`;
 }, (first, middle, last));

 return < h1 >Welcome, {Name}!</ h1 >;
 };

 export const UseMemoApp = => {
 const (first, setFirst) = useState('John');
 const (middle, setMiddle) = useState('Adam');
 const (last, setLast) = useState('Doe');
 return (
  <div>
   <input
    type="text"
    value={first}
    onChange={e => setFirst(e.target.value)}
   />
   <input
    type="text"
    value={middle}
    onChange={e => setMiddle(e.target.value)}
   />
   <input
    type="text"
    value={last}
    onChange={e => setLast(e.target.value)}
   />
   <UseMemoExample first={first} middle={middle} last={last} />
  </div>
 );
 };

The component displays a Name constant as output which is the concatenation of the person's first, middle and last name.

In React, the useMemo hook increases application efficiency and performance.

6. Custom hooks

Custom hooks allow developers to encapsulate and share functionality across different components. The following is an example to demonstrate the custom hook that describes the window dimension implementation.

We created a custom hook called CustomHooksToCheckWindowDimensions that returns the W and H of the window as an output where W is the width and H is the height of the window. We are using the useState and useEffect hooks to determine the window dimension and modify the state value whenever the window is resized.

CustomHooksToCheckWindowDimensions uses the useState hook to initialize the state value by reaching the inner width and height of the window using the window.innerWidth and window.innerHeight properties.

The useEffect hook helps in monitoring the modification of the window dimension. Additionally, when the window is resized, the resize function passed to addEventListener is invoked, which invokes setDim to reflect the new window size.

 import React, { useState, useEffect } from 'react';

 function CustomHooksToCheckWindowDimensions {
 const (dim, setDim) = useState({
  W: window.innerWidth,
  H: window.innerHeight
 });

 useEffect( => {
  function resizing {
   setDim({
    W: window.innerWidth,
    H: window.innerHeight
   });
  }

  window.addEventListener('resize', resizing);
  return => {
   window.removeEventListener('resize', resizing);
  };
 }, );

 return dim;
 }

Lastly, the CustomHookApp component calls CustomHooksToCheckWindowDimensions, which returns the width and height of the window. The window dimension will be displayed as output.

 function CustomHookApp {
 const { W, H } = CustomHooksToCheckWindowDimensions ;
 
return (
 < div >
 < h1 >Dimension of the Window is:</ h1 >
 < p >Width: {W}</ p >
 < p >Height: {H}</ p >
 </ div >
 );
 }

 export default CustomHookApp;

Custom hooks allow you to handle various use cases, such as form manipulation and timers, that were not possible before.

Advantages of using React hooks

This section will explore the advantages of using hooks. Following are the benefits of using hooks instead of class components:

Code Reuse and Conciseness

Using custom hooks allows for encapsulation of logic and reuse of logic across multiple components, improving code modularity, understandability, performance, and maintainability. Additionally, employing hooks helps minimize boilerplate code when creating components, which increases conciseness and makes the code easier to understand.

Best performance

In React, hooks allow developers to optimize components using various methods and approaches, including useMemo and useCallback, which helps improve application performance.

Improved readability and developer productivity

In React, hooks are an essential tool that increases the understandability of the logical flow and data present in components, which leads to better readability and ease of debugging. Additionally, it speeds up the development process, making code and component maintenance easier to understand.

Better accessibility and community support

Encapsulating the logic of accessibility features in custom hooks and reusing them in your application becomes simpler with the help of hooks. In addition to being a fully supported component of the React ecosystem, the hooks library has a sizable and active community of developers who actively collaborate and share knowledge and tools.

Better state management

Hooks simplify component state management by encapsulating the logic for updating and modifying state in discrete, reusable hooks.

Improve code sharing and simplified testing

The logic in hooks can be tested independently of the components that use them, which facilitates efficient unit testing. Additionally, custom hooks can share code among team members and make code reuse easier when working on a complicated project within a large group.

Hooks in React offer several advantages that improve code quality, performance, and maintainability and simplify the development process. With the help of hooks, an individual can create a dynamic, optimized, and scalable application in React.

Final thoughts

React Hooks provide a robust and flexible approach to creating components in React. They allow for simpler, more understandable and easier to maintain code. By using Hooks, developers can create complicated applications with less overall complexity and fewer lines of source code. They also provide a simple means of managing state across multiple components without the need for class-based components or global state libraries like Redux. You must know how to use React Hooks to leverage their full potential when developing applications.

If you liked this, be sure to check out our other articles on React.

• Top React Interview Questions and Answers You Need to Know
• Unit Testing in React: Detailed Guide
• What projects can your company use React for?
• What you need to know about React before using it in your business
• 6 reasons why React is so popular