Easily scan QR and ean codes in your React application. Exports a handy useZxing hook that utilizes the popular @zxing/library to stream video to an element and decode codes from it.

Usage

import { useState } from "react";
import { useZxing } from "react-zxing";

export const BarcodeScanner = () => {
  const [result, setResult] = useState("");
  const { ref } = useZxing({
    onDecodeResult(result) {
      setResult(result.getText());
    },
  });

  return (
    <>
      <video ref={ref} />
      <p>
        <span>Last result:</span>
        <span>{result}</span>
      </p>
    </>
  );
};

With specific device ID

You could either get the device ID from the MediaDevices API yourself or make use of react-media-devices to list available devices:

import { useMediaDevices } from "react-media-devices";
import { useZxing } from "react-zxing";

const constraints: MediaStreamConstraints = {
  video: true,
  audio: false,
};

export const BarcodeScanner = () => {
  const { devices } = useMediaDevices({ constraints });
  const deviceId = devices?.[0]?.deviceId;
  const { ref } = useZxing({
    paused: !deviceId,
    deviceId,
  });

  return <video ref={ref} />;
};

Advanced Usage

Torch

⚠️ Torch support is not available for iOS devices. See this issue.

You can control the torch by accessing the torch property of the useZxing return value:

import { useZxing } from "react-zxing";

export const BarcodeScanner = () => {
  const {
    ref,
    torch: { on, off, isOn, isAvailable },
  } = useZxing();

  return (
    <>
      <video ref={ref} />
      {isAvailable ? (
        <button onClick={() => (isOn ? off() : on())}>
          {isOn ? "Turn off" : "Turn on"} torch
        </button>
      ) : (
        <strong>Unfortunately, torch is not available on this device.</strong>
      )}
    </>
  );
};

Torch support is limited to devices that support the torch constraint. You can check if torch is available by checking the isAvailable property.

Options

Development

# Install dependencies
yarn
# Build the library
yarn build
# Install example dependencies
yarn --cwd example
# Start the example
yarn --cwd example start

Example should now be running on localhost:1234.