How to Make a Download Progress Bar in React
Have you ever wondered how to show a download progress bar in your React app? A download progress bar is a useful feature that can enhance the user experience and provide feedback about the status of a file download. In this tutorial, we will learn how to make a simple but effective download progress bar in React using Axios, a popular library for making HTTP requests.
Axios allows us to track the progress of a file download using the onDownloadProgress option, which takes a callback function that receives a progress event object. This object contains information such as the number of bytes loaded and the total size of the request. From this, we can calculate the percentage of the download progress and update the state and the UI accordingly. We will also use React hooks to manage the state changes and handle errors and success messages.
download progress bar react
By the end of this tutorial, you will have a working download progress bar that looks something like this:
Setting up the project
To get started, we need to set up a React project using create-react-app, a tool that allows us to create a React app with minimal configuration. To do this, open your terminal and run the following command:
npm create-react-app react-download-progress-bar
This will create a new folder called react-download-progress-bar with all the necessary files and dependencies. Next, we need to install Axios, which we will use for making HTTP requests. To do this, run the following command inside the project folder:
npm install axios
Now we are ready to start coding. Open your favorite code editor and navigate to the src folder. Here you will find a file called App.js, which is the main component of our app. We will replace its content with our own code.
How to make a download progress bar in React with Axios[^1^]
React: download a file with Axios using a progress bar[^2^]
Circular, linear progress React components - Material UI[^3^]
React download button with progress indicator
How to use React hooks for download progress state
React file download component with progress bar
How to create a custom download progress bar in React
React download manager with progress and pause/resume features
How to show download progress in React Native
React progress bar tutorial - Learn how to create a simple and responsive progress bar in React
How to use React Bootstrap for download progress bar
React download file with fetch and show progress
How to implement a circular download progress bar in React using SVG
React download PDF with progress bar example
How to use React Spring for animating download progress bar
React download image with progress bar and preview
How to create a multi-step download progress bar in React
React download CSV with progress bar and save as dialog
How to use React Redux for managing download progress state
React download video with progress bar and playback controls
How to create a radial download progress bar in React using Canvas
React download zip file with progress bar and unzip functionality
How to use React Router for navigating between download steps and showing progress bar
React download audio with progress bar and audio player
How to use React Testing Library for testing download progress bar component
React download JSON with progress bar and JSON viewer
How to create a skeleton download progress bar in React for loading state
React download Excel file with progress bar and open in Excel option
How to use React Context for passing download progress data between components
React download multiple files with progress bar and batch download option
How to create a custom shape download progress bar in React using CSS clip-path
React download text file with progress bar and edit option
How to use React Query for fetching data and showing download progress bar
React download HTML file with progress bar and render option
How to use React Icons for adding icons to download progress bar component
React download APK file with progress bar and install option
How to create a countdown timer for download progress bar in React
React download GIF file with progress bar and GIF player
How to use React Hook Form for validating user input before downloading data and showing progress bar
React download XML file with progress bar and XML parser
How to create a rainbow effect for download progress bar in React using CSS gradients
React download DOCX file with progress bar and open in Word option
How to use React Lazy Load for loading images only when they are visible in the viewport and showing download progress bar
React download PPTX file with progress bar and open in PowerPoint option
How to use React D3 for creating data visualizations and showing download progress as charts or graphs
React download MP4 file with progress bar and video player
How to use React Helmet for changing the title of the page based on the download status and progress percentage
React download SVG file with progress bar and SVG editor
How to use React Toastify for showing notifications or alerts when the download is completed or failed and showing the final progress percentage
First, let's import React and Axios at the top of the file:
import React from 'react'; import axios from 'axios';
Next, let's add some CSS styles for our download button and our progress bar. We will use CSS variables to control some properties such as the color, width, and height of the elements. You can paste these styles inside the App.css file or use inline styles if you prefer:
.progress-button position: relative; display: flex; align-items: center; justify-content: center; width: 300px; height: 80px; .download-button position: absolute; width: var(--button-width); height: var(--button-height); border: none; border-radius: var(--button-height); background-color: var(--button-color); color: white; font-size: var(--font-size); .loading-text position: absolute; opacity: 0; color: white; font-size: var(--font-size); .percentage position: absolute; color: white; font-size: var(--font-size); .in-progress .download-button width: var(--progress-width); .in-progress .loading-text opacity: 1; .finished .download-button width: var(--button-width); .finished .percentage opacity: 0; /* CSS variables */ :root --button -width: 300px; --button-height: 80px; --button-color: #2196f3; --progress-width: calc(var(--button-width) * var(--progress)); --font-size: 24px;
As you can see, we have four classes for our elements: progress-button, download-button, loading-text, and percentage. We also have two modifier classes: in-progress and finished, which we will use to change the appearance of the elements based on the download state. The progress-button class is the container for all the other elements. The download-button class is the actual button that the user can click to start the download. The loading-text class is the text that shows "Loading..." when the download is in progress. The percentage class is the text that shows the percentage of the download progress.
Now let's create our React component and add some initial state and UI. We will use React hooks to manage the state changes and handle the events. We will use four state variables: progress, which will store the percentage of the download progress; inProgress, which will indicate whether the download is in progress or not; finished, which will indicate whether the download is finished or not; and error, which will store any error message that may occur during the download. We will also use a constant called fileUrl, which will store the URL of the file that we want to download. For this tutorial, we will use a sample PDF file from Wikipedia, but you can use any file you want.
function App() // State variables const [progress, setProgress] = React.useState(0); const [inProgress, setInProgress] = React.useState(false); const [finished, setFinished] = React.useState(false); const [error, setError] = React.useState(null); // File URL const fileUrl = " // UI elements return (
Download
Loading...
progress%
error && error
);
Here we have created a function component called App, which returns a JSX element that contains our UI elements. We have a div with the class progress-button, which contains a button with the class download-button, a span with the class loading-text, and another span with the class percentage. We also have a conditional rendering of a p element with the class error, which will show any error message that may occur during the download. We have also added some logic to change the class names of the button based on the inProgress and finished state variables. Finally, we have added an onClick event handler to the button, which will call a function called download when the user clicks it.
Implementing the download function
Now let's implement the download function that will handle the actual file download using Axios. We will use Axios to make a GET request to the file URL with some options, such as responseType and onDownloadProgress. The responseType option tells Axios what type of data we expect to receive from the server. In this case, we want to receive a blob, which is a binary representation of the file data. The onDownloadProgress option takes a callback function that receives a progress event object, which contains information such as loaded and total. The loaded property tells us how many bytes have been downloaded so far, and the total property tells us how many bytes are expected to be downloaded in total. From these properties, we can calculate the percentage of the download progress using this formula:
const percentage = Math.round((loaded * 100) / total);
We can then use this percentage value to update our state and UI using React hooks. We will use setProgress to update the progress state variable, setInProgress to update the inProgress state variable, and setFinished to update the finished state variable. We will also use setError to update the error state variable if any error occurs during the download.
Here is how our download function looks like:
function download() // Reset the state setProgress(0); setInProgress(true); setFinished(false); setError(null); // Make a GET request to the file URL axios .get(fileUrl, responseType: "blob", onDownloadProgress: (event) => // Calculate the percentage of the download progress const percentage = Math.round((event.loaded * 100) / event.total); // Update the state and the UI setProgress(percentage); , ) .then((response) => // Create a URL for the blob object const url = window.URL.createObjectURL(new Blob([response.data])); // Create a link element and set its attributes const link = document.createElement("a"); link.href = url; link.setAttribute("download", "file.pdf"); // Append the link to the document body and click it document.body.appendChild(link); link.click(); // Remove the link from the document body document.body.removeChild(link); // Update the state and the UI setInProgress(false); setFinished(true); ) .catch((error) => // Update the state and the UI setInProgress(false); setError(error.message); );
As you can see, we have used Axios to make a GET request to the file URL with some options. We have used a then method to handle the successful response, and a catch method to handle any error. In the then method, we have created a URL for the blob object using window.URL.createObjectURL, which creates a temporary URL that points to the blob object. We have then created a link element and set its href attribute to the blob URL, and its download attribute to the file name. We have then appended the link to the document body and clicked it, which will trigger the browser to download the file. We have then removed the link from the document body and updated our state and UI accordingly. In the catch method, we have simply updated our state and UI with the error message.
Conclusion
In this tutorial, we have learned how to make a download progress bar in React using Axios. We have seen how to use Axios to track the progress of a file download using onDownloadProgress, and how to update our state and UI using React hooks. We have also seen how to create a blob URL and a link element to download the file from the browser.
This is a simple but effective way to show a download progress bar in your React app, but there are some possible improvements and extensions that you can try. For example, you can:
Use different files or URLs for testing purposes
Customize the appearance of the progress bar using CSS or other libraries
Download multiple files at once using Promise.all or async/await
Test the performance of the download function using tools such as Chrome DevTools
We hope you enjoyed this tutorial and learned something new. If you have any questions or feedback, feel free to leave a comment below.
FAQs
What is Axios and how does it work?
Axios is a popular library for making HTTP requests in JavaScript. It works both in the browser and in Node.js, and supports features such as promises, interceptors, cancellation, progress events, and more. Axios works by creating an instance of XMLHttpRequest (in the browser) or http (in Node.js) and sending requests using various methods such as get, post, put, delete, etc. Axios also provides some useful helpers and defaults that make it easier to work with HTTP requests.
What are React hooks and why are they useful?
React hooks are functions that let you use state and other React features without writing a class component. They allow you to write more concise and functional code, and avoid some common pitfalls of class components such as this binding, lifecycle methods, and inheritance. Some of the built-in hooks are useState, useEffect, useRef, useContext, useReducer, etc. You can also create your own custom hooks by combining other hooks.
How can I customize the appearance of the progress bar?
You can customize the appearance of the progress bar using CSS or other libraries that provide ready-made components or styles for progress bars. For example, you can use Bootstrap, Material-UI, Ant Design, etc. You can also use CSS animations or transitions to add some effects or transitions to the progress bar.
How can I download multiple files at once?
You can download multiple files at once by using Promise.all or async/await to handle multiple requests simultaneously. Promise.all takes an array of promises and returns a single promise that resolves when all of them are fulfilled or rejects when any of them fails. async/await lets you write asynchronous code in a synchronous way by using await keyword to pause the execution until a promise is resolved or rejected. For example, you can write something like this: async function downloadAll() // An array of file URLs const fileUrls = [ " " " ]; // An array of promises const promises = fileUrls.map((fileUrl) => axios.get(fileUrl, responseType: "blob" )); // Wait for all promises to resolve const responses = await Promise.all(promises); // Loop through the responses and download the files responses.forEach((response, index) => // Create a URL for the blob object const url = window.URL.createObjectURL(new Blob([response.data])); // Create a link element and set its attributes const link = document.createElement("a"); link.href = url; link.setAttribute("download", `file$index + 1.pdf`); // Append the link to the document body and click it document.body.appendChild(link); link.click(); // Remove the link from the document body document.body.removeChild(link); );
This function will download all the files in the fileUrls array at once and save them as file1.pdf, file2.pdf, and file3.pdf. You can call this function in the onClick event handler of the download button instead of the download function.
How can I test the performance of the download function?
You can test the performance of the download function using tools such as Chrome DevTools, which provide various features and metrics to measure and analyze the performance of your web app. For example, you can use the Network panel to monitor the network activity and see how long it takes to download the file, how much data is transferred, what is the status code, etc. You can also use the Performance panel to record and inspect the runtime performance of your app, such as CPU usage, memory consumption, rendering time, etc. You can also use tools such as Lighthouse or WebPageTest to audit and benchmark your web app against best practices and standards. 44f88ac181
Comments