How to Create a Pop-Up Modal in React

What is a modal?

A modal is a box that appears on the page, blocking all functions to concentrate focus on a particular action. This is their differentiating feature, they ask the user to perform an action.
To return to the main content, the user must engage with the modal by completing an action or by closing it.

Let's create a modal with React

Code on GitHub: https://github.com/nicvazquez/react-modal
Demo: https://react-modal-nicvazquez.vercel.app/

Step 1: Create App

Let's create the React app with Vite using the following command:

npm create vite@latest

After this, it will ask us to complete with some options:

√ Project name: ... react-modal
√ Select a framework: » react
√ Select a variant: » react

Excellent! Now run the following commands:

cd react-modal
npm install
npm run dev

If everything went well, you should have the application created, with the dependencies installed and have the project running on a local server, which in my case is http://127.0.0.1:5173/.

Step 2: Let's create the base of our application

Open App.jsx and create the button element. Your code should look like this:

import "./App.css";

function App() {
    return (
        <div className="container">
            <button>Open Modal</button>
        </div>
    );
}

export default App;

Modify the App.css file. The styles should look like this:

.container {
    display: grid;
    place-items: center;
    width: 100%;
    height: 100vh;
}

Now modify index.css:

:root {
    font-family: Inter, Avenir, Helvetica, Arial, sans-serif;
    color-scheme: light dark;
    color: rgba(255, 255, 255, 0.87);
    background-color: #242424;
}

button {
    border-radius: 8px;
    border: 1px solid transparent;
    padding: 0.6em 1.2em;
    font-size: 1em;
    font-weight: 500;
    font-family: inherit;
    background-color: #1a1a1a;
    cursor: pointer;
    transition: border-color 0.25s;
}
button:hover {
    border-color: #646cff;
}
button:focus,
button:focus-visible {
    outline: 4px auto -webkit-focus-ring-color;
}

@media (prefers-color-scheme: light) {
    button {
        background-color: #f9f9f9;
    }
}

If we go to our local server, we should have the following:

Step 3: Let's create the modal

In the src folder, let's create the components folder and inside it we need to create another folder called Modal, which should contain the Modal.jsx and modal.module.css files.

The structure of our project should look something like this:

REACT-MODAL
└─── node_modules
└─── public    
│
└─── src
│   │
│   └─── assets
│   |       react.svg
│   └─── components \ Modal
│   |        Modal.jsx
│   |        modal.module.css
|   |   App.css
|   |   App.jsx
|   |   index.css
|   |   main.jsx
│   
|   .gitignore
|   index.html
|   package-lock.json
|   package.json
|   vite.config.js

To give structure to the modal, we must add the HTML to it in Modal.jsx:

import React from "react";
import styles from "./modal.module.css";

export const Modal = () => {
    return (
        <div className={styles.modalBack}>
            <div className={styles.modalContainer}>
                <div>
                    <h2>Modal</h2>
                    <p>
                        Lorem ipsum dolor sit amet consectetur adipisicing elit. Ex, nisi. Dolorem est
                        esse iste perferendis.
                    </p>
                </div>
                <button className={styles.modal__closeBtn}>Close</button>
            </div>
        </div>
    );
};

To style the modal, we must have this code in modal.module.css:

.modalBack {
    position: absolute;
    height: 100vh;
    width: 100%;
    display: grid;
    place-items: center;
    background-color: rgba(0, 0, 0, 0.322);
}

.modalContainer {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: flex-start;
    height: 30%;
    max-width: 60%;
    background-color: rgb(39, 43, 114);
    padding: 3rem;
    border-radius: 5px;
}

Let's go to App.jsx and import the Modal

import "./App.css";
import { Modal } from "./components/Modal/Modal";

function App() {
    return (
        <div className="container">
            <button>Open Modal</button>
            <Modal />
        </div>
    );
}

export default App;

Your modal should look like this:

So far so good, but one thing is missing... show the modal when the user clicks on the button.
Let's get to it!

Step 4: Being able to open the modal

Go to App.jsx and import useState:

import { useState } from "react";

Let's declare the useState with the default value false:

const [showModal, setShowModal] = useState(false)

Let's add the onClick function and the conditional to display the modal:

<button onClick={() => setShowModal(true)}>Open Modal</button>
{showModal && <Modal />}

Our App.jsx should look like this:

import { useState } from "react";
import "./App.css";
import { Modal } from "./components/Modal/Modal";

function App() {
    const [showModal, setShowModal] = useState(false);
    return (
        <div className="container">
            <button onClick={() => setShowModal(true)}>Open Modal</button>
            {showModal && <Modal />}
        </div>
    );
}

export default App;

Now if we click the button, the modal should appear. We are doing well, but we still need to close the modal

Step 5: Being able to close the modal

We must go to the Modal.jsx file and pass a prop as a parameter to close the modal.

export const Modal = ({ closeModal }) => {

Put that prop as onClick event to the button of the modal:

<button onClick={closeModal} className={styles.modal__closeBtn}>
    Close Modal
</button>

If we want also to close the modal when clicked outside of it, we can pass the prop to the parent div

<div onClick={closeModal} className={styles.modalBack}>

Our Modal.jsx should look like this:

import React from "react";
import styles from "./modal.module.css";

export const Modal = ({ closeModal }) => {
    return (
        <div onClick={closeModal} className={styles.modalBack}>
            <div className={styles.modalContainer}>
                <div>
                    <h2>Modal</h2>
                    <p>
                        Lorem ipsum dolor sit amet consectetur adipisicing elit. Ex, nisi. Dolorem est
                        esse iste perferendis.
                    </p>
                </div>
                <button onClick={closeModal} className={styles.modal__closeBtn}>
                    Close Modal
                </button>
            </div>
        </div>
    );
};

Now we need to send the function as props from App.jsx for the onClick event to work

{showModal && <Modal closeModal={() => setShowModal(false)} />}

Our App.jsx should finally look like this:

import { useEffect, useState } from "react";
import "./App.css";
import { Modal } from "./components/Modal/Modal";

function App() {
    const [showModal, setShowModal] = useState(false);

    return (
        <div className="container">
            <button onClick={() => setShowModal(true)}>Open Modal</button>

            {showModal && <Modal closeModal={() => setShowModal(false)} />}
        </div>
    );
}

export default App;