React Get Screen Width: Everything You Need To Know

In web development, creating responsive interfaces that adapt to various screen sizes is crucial. Accessing the dimensions of the browser window is essential for responsive design, as it allows developers to dynamically adjust the layout based on the window's width and height.

The react get screen width functionality plays a pivotal role in this aspect. It allows developers to access the window width and adjust the layout and elements accordingly. This ensures that the React app remains visually appealing and functional across different devices.

This blog will explore various methods to effectively retrieve the screen width in React. Let's get started!

Understanding screen width in React

React, being a powerful library, offers various ways to create responsive designs. One of the key features is its ability to re-render components efficiently when the screen size changes. This is where understanding how to obtain the screen width becomes essential. Let’s delve into the methods and react hooks that can help us achieve this.

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1import React, { useState, useEffect } from "react";
2
3const useWindowDimensions = () => {
4  const [windowDimensions, setWindowDimensions] = useState({
5    width: window.innerWidth,
6    height: window.innerHeight,
7  });
8
9  useEffect(() => {
10    const handleResize = () => {
11      setWindowDimensions({
12        width: window.innerWidth,
13        height: window.innerHeight,
14      });
15    };
16    window.addEventListener("resize", handleResize);
17    return () => window.removeEventListener("resize", handleResize);
18  }, []);
19
20  return windowDimensions;
21};
22
23export default useWindowDimensions;

How to Get the Screen Width in React?

Utilizing the window.innerWidth Property

To get the screen width in a React component, you can directly use the window.innerWidth property to access the width of the browser window. This property provides the width of the browser window’s content area. However, it’s important to note that this approach might not be reactive to window resize events. To make it reactive, you would need to add an event listener for the resize event and update the state accordingly.

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1import React, { useState, useEffect } from "react";
2
3const App = () => {
4  const [width, setWidth] = useState(window.innerWidth);
5
6  useEffect(() => {
7    const handleResize = () => setWidth(window.innerWidth);
8    window.addEventListener("resize", handleResize);
9    return () => window.removeEventListener("resize", handleResize);
10  }, []);
11
12  return (
13    <div>
14      {" "}
15      <p>The width of the screen is: {width}px</p>{" "}
16    </div>
17  );
18};
19
20export default App;

Crafting a Custom Hook for Window Width in React

useWindowDimensions Hook: A Dynamic Approach

Creating a custom hook such as useWindowDimensions can provide a more elegant solution. This hook encapsulates the logic for listening to browser window width and height changes and provides a return value that can be used across multiple components. It’s a prime example of reusability and abstraction in React.

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1import { useState, useEffect } from "react";
2
3const useWindowDimensions = () => {
4  const [dimensions, setDimensions] = useState({
5    width: window.innerWidth,
6    height: window.innerHeight,
7  });
8
9  useEffect(() => {
10    const handleResize = () => {
11      setDimensions({ width: window.innerWidth, height: window.innerHeight });
12    };
13    window.addEventListener("resize", handleResize);
14    return () => window.removeEventListener("resize", handleResize);
15  }, []);
16
17  return dimensions;
18};
19
20export default useWindowDimensions;

React Hook for Screen Width

Implementing useState and useEffect Hooks

The useState hook is used to store the initial value of the width and height of the browser window in React, while the useEffect hook is employed to perform side effects, such as setting up an event listener for the resize event. The combination of these two hooks allows us to create a responsive React app that adjusts to changes in window dimensions.

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1import React, { useState, useEffect } from "react";
2
3const useScreenWidth = () => {
4  const [screenWidth, setScreenWidth] = useState(window.innerWidth);
5
6  useEffect(() => {
7    const handleResize = () => setScreenWidth(window.innerWidth);
8    window.addEventListener("resize", handleResize);
9    return () => window.removeEventListener("resize", handleResize);
10  }, []);
11
12  return screenWidth;
13};
14
15export default useScreenWidth;

Managing Window Resize Events in React

Creating a Robust function handleResize

To manage window resize events effectively, it’s important to define a function called handleResize that updates the state with the new browser window width and height. This function should be debounced or throttled to avoid performance issues due to frequent re renders. Additionally, a cleanup function should be included to remove the event listener when the component unmounts, preventing potential memory leaks.

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1import { useState, useEffect } from "react";
2import { debounce } from "lodash";
3
4const useDebouncedResize = () => {
5  const [size, setSize] = useState({
6    width: window.innerWidth,
7    height: window.innerHeight,
8  });
9
10  useEffect(() => {
11    const handleResize = debounce(() => {
12      setSize({ width: window.innerWidth, height: window.innerHeight });
13    }, 100);
14    window.addEventListener("resize", handleResize);
15    return () => {
16      handleResize.cancel();
17      window.removeEventListener("resize", handleResize);
18    };
19  }, []);
20
21  return size;
22};
23
24export default useDebouncedResize;

Optimizing Performance with Cleanup Functions

Preventing Memory Leaks in Event Listeners

In React, it’s crucial to clean up side effects to maintain application performance and prevent memory leaks, especially when tracking the dimensions of the browser window. This is where cleanup functions come into play. When setting up an event listener in a useEffect hook, always return a function that removes the listener. This is particularly important in the context of window resize events, as they can be triggered frequently, leading to potential issues if not handled correctly.

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1import React, { useState, useEffect } from "react";
2
3const useResponsiveWidth = () => {
4  const [width, setWidth] = useState(window.innerWidth);
5
6  useEffect(() => {
7    const handleResize = () => setWidth(window.innerWidth);
8    window.addEventListener("resize", handleResize);
9    // Cleanup function to remove the event listener
10    return () => window.removeEventListener("resize", handleResize);
11  }, []);
12
13  return width;
14};
15
16export default useResponsiveWidth;

React Native and Screen Dimensions

Leveraging the Dimensions Module in React Native

When working with React Native, the approach to obtaining screen width and height differs from web development. React Native provides a dimensions module that can be used to get screen dimensions. This module offers an API to access the width and height of the screen, which is essential for creating responsive layouts in mobile applications.

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1import { Dimensions } from "react-native";
2
3const window = Dimensions.get("window");
4const screen = Dimensions.get("screen");
5
6console.log(`Window dimensions: ${window.width}x${window.height}`);
7console.log(`Screen dimensions: ${screen.width}x${screen.height}`);

Practical Examples: React Get Screen Width in Action

Building a Responsive Component with Dynamic Styles

To put our knowledge into practice, let’s build a responsive React component that adjusts its styles based on the width of the browser window. By using the useWindowDimensions hook, we can dynamically set the const styles and ensure our component looks great on any screen size.

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1import React from "react";
2import useWindowDimensions from "./hooks/useWindowDimensions";
3
4const ResponsiveComponent = () => {
5  const { width } = useWindowDimensions();
6  const styles = {
7    container: {
8      width: "100%",
9      backgroundColor: width > 768 ? "blue" : "green",
10    },
11    text: { color: "white" },
12  };
13
14  return (
15    <div style={styles.container}>
16      {" "}
17      <p style={styles.text}>Resize the window to see the color change!</p>{" "}
18    </div>
19  );
20};
21
22export default ResponsiveComponent;

The Bottom Line!

Mastering the ability to react get screen width is a fundamental skill for any developer looking to create responsive React apps. By understanding and implementing the techniques discussed, such as custom hooks, event listeners, and the useEffect hook, you can ensure that your components adapt seamlessly to different screen sizes. This not only enhances the user experience but also showcases your capability to tackle modern web development challenges.