I am receiving an error in react when trying to add a download option for a generated QR code. The error states “Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()?”. Note that I am new to react and not sure where to implement this “forwardRef” option. Here is my code:
import React, { useState, useRef } from "react";
import {
Container,
Row,
Col,
Button,
ToggleButtonGroup,
ToggleButton,
InputGroup,
FormControl,
} from "react-bootstrap";
import QRCode from "qrcode.react";
const LinkQRPage = () => {
const [link, setLink] = useState(""); // State for input link
const [qrOptions, setQROptions] = useState({
size: 256,
bgColor: "#FFFFFF",
fgColor: "#000000",
level: "H",
includeMargin: false,
imageOptions: {
type: "url",
src: "",
file: null,
width: 40,
height: 40,
},
});
const qrCanvasRef = useRef(null); // Ref to hold QR code canvas element
// Function to handle form submission
const handleSubmit = (e) => {
e.preventDefault();
console.log(
"Generating QR code with link:",
link,
"and options:",
qrOptions
);
};
// Function to handle input change for link
const handleLinkChange = (e) => {
setLink(e.target.value);
};
// Function to handle input change for styling options
const handleOptionChange = (name, value) => {
setQROptions((prevState) => ({
...prevState,
[name]: value,
}));
};
// Function to handle file upload for image
const handleFileUpload = (e) => {
const file = e.target.files[0];
if (file) {
const reader = new FileReader();
reader.readAsDataURL(file);
reader.onloadend = () => {
setQROptions((prevState) => ({
...prevState,
imageOptions: {
...prevState.imageOptions,
type: "file",
src: reader.result,
file: file,
},
}));
};
}
};
// Function to handle QR code size change
const handleQRSizeChange = (e) => {
const newSize = parseInt(e.target.value, 10);
setQROptions((prevState) => ({
...prevState,
size: newSize,
}));
};
// Function to handle downloading the QR code
const handleDownload = () => {
if (qrCanvasRef.current !== null) {
const canvas = qrCanvasRef.current._canvas; // Accessing the canvas element
const imageDataUrl = canvas.toDataURL("image/png");
const downloadLink = document.createElement("a");
downloadLink.href = imageDataUrl;
downloadLink.download = "QRCode.png";
document.body.appendChild(downloadLink);
downloadLink.click();
document.body.removeChild(downloadLink);
}
};
return (
<Container className="mt-5 mb-5">
<Row>
<Col md={8} className="left-side-qr">
<h1>LinkQR</h1>
<form onSubmit={handleSubmit}>
<div className="mb-3">
<label htmlFor="linkInput" className="form-label">
Link
</label>
<input
type="text"
className="form-control"
id="linkInput"
placeholder="Enter your link"
value={link}
onChange={handleLinkChange}
/>
</div>
<div className="mb-3">
<label htmlFor="sizeInput" className="form-label">
QR Code Size
</label>
<input
type="number"
className="form-control"
id="sizeInput"
name="size"
value={qrOptions.size}
onChange={handleQRSizeChange}
min="64"
max="256"
/>
</div>
<div className="mb-3">
<label htmlFor="bgColorInput" className="form-label">
Background Color
</label>
<input
type="color"
className="form-control"
id="bgColorInput"
name="bgColor"
value={qrOptions.bgColor}
onChange={(e) =>
handleOptionChange(e.target.name, e.target.value)
}
/>
</div>
<div className="mb-3">
<label htmlFor="fgColorInput" className="form-label">
Foreground Color
</label>
<input
type="color"
className="form-control"
id="fgColorInput"
name="fgColor"
value={qrOptions.fgColor}
onChange={(e) =>
handleOptionChange(e.target.name, e.target.value)
}
/>
</div>
<div className="mb-3">
<label className="form-label">Image Type</label>
<ToggleButtonGroup
type="radio"
name="imageType"
value={qrOptions.imageOptions.type}
onChange={(value) => handleOptionChange("imageType", value)}
>
<ToggleButton id="url-toggle" value="url">
URL
</ToggleButton>
<ToggleButton id="file-toggle" value="file">
Upload
</ToggleButton>
</ToggleButtonGroup>
</div>
{qrOptions.imageOptions.type === "url" && (
<div className="mb-3">
<label htmlFor="imageSrcInput" className="form-label">
Image Source (URL)
</label>
<input
type="text"
className="form-control"
id="imageSrcInput"
name="imageSrc"
placeholder="Enter image URL"
value={qrOptions.imageOptions.src}
onChange={(e) =>
handleOptionChange("imageSrc", e.target.value)
}
/>
</div>
)}
{qrOptions.imageOptions.type === "file" && (
<div className="mb-3">
<label htmlFor="imageFileInput" className="form-label">
Upload Image
</label>
<input
type="file"
className="form-control"
id="imageFileInput"
name="imageFile"
onChange={handleFileUpload}
/>
</div>
)}
<div className="mb-3">
<label htmlFor="imageWidthInput" className="form-label">
Image Width (Optional)
</label>
<InputGroup>
<FormControl
type="number"
id="imageWidthInput"
name="imageWidth"
placeholder="Width"
value={qrOptions.imageOptions.width}
onChange={(e) =>
handleOptionChange("imageWidth", e.target.value)
}
aria-label="Image width"
/>
<InputGroup.Text>px</InputGroup.Text>
</InputGroup>
</div>
<div className="mb-3">
<label htmlFor="imageHeightInput" className="form-label">
Image Height (Optional)
</label>
<InputGroup>
<FormControl
type="number"
id="imageHeightInput"
name="imageHeight"
placeholder="Height"
value={qrOptions.imageOptions.height}
onChange={(e) =>
handleOptionChange("imageHeight", e.target.value)
}
aria-label="Image height"
/>
<InputGroup.Text>px</InputGroup.Text>
</InputGroup>
</div>
<Button variant="primary" type="submit">
Generate QR Code
</Button>
</form>
</Col>
<Col
md={4}
className="right-side-qr d-flex align-items-center justify-content-center"
>
<div style={{ width: "100%", textAlign: "center" }}>
<h1>Preview</h1>
<div style={{ width: "80%", margin: "0 auto" }}>
<QRCode
ref={qrCanvasRef} // Ref to access QR code canvas element
size={256} // Fixed size for the preview
value={link}
bgColor={qrOptions.bgColor}
fgColor={qrOptions.fgColor}
includeMargin={qrOptions.includeMargin}
imageSettings={{
src: qrOptions.imageOptions.src,
x: null,
y: null,
height: qrOptions.imageOptions.height,
width: qrOptions.imageOptions.width,
excavate: true,
}}
/>
</div>
<div className="mt-3">
<Button variant="success" onClick={handleDownload}>
Download QR Code
</Button>
</div>
</div>
</Col>
</Row>
</Container>
);
};
export default LinkQRPage;
I tried multiple suggestions, but unsure where to implement it. Just looking for advice or pointers in the right direction.