Challenge Overview:
I am facing discrepancies in the PDF images generated with Html2Canvas on various devices. While the design looks fine on my laptop, it shows inconsistencies on other devices like phones or different laptops. I suspect that these differences may be due to varying screen resolutions.
Snippet of Code:
const DownloadBarcodes = async () => {
try {
const { isConfirmed } = await getBarcodeText();
if (isConfirmed) {
const pdf = new jsPDF({
unit: "mm",
format: "a4",
});
const imgWidth = 210;
const imgHeight = 296;
const qrCodeContainer = document.createElement("div");
qrCodeContainer.style.width = `${imgWidth}mm`;
qrCodeContainer.style.height = `${imgHeight}mm`;
document.body.appendChild(qrCodeContainer);
const root = createRoot(qrCodeContainer);
for (let j = 0; j < 2; j++) {
const headerText = j === 0 ? "Good morning !" : "Good evening ! ";
for (let i = 0; i < qrCodes.length + 1; i++) {
const firstName = await extractNameWithoutNumber(
qrCodes[i]?.waiterName.split(" ")[0]
);
root.render(
<BarcodePaperTemplate
url={qrCodes[i]?.url}
name={firstName}
headerText={headerText}
/>
);
const canvas = await html2canvas(qrCodeContainer, {
willReadFrequently: true,
});
const qrCodeDataUrl = canvas.toDataURL("image/png");
if (i > 0) {
pdf.addImage(qrCodeDataUrl, "PNG", 0, 0, imgWidth, imgHeight);
if (i < qrCodes.length + 1) {
pdf.addPage();
}
}
}
}
pdf.deletePage(pdf.internal.getNumberOfPages());
document.body.removeChild(qrCodeContainer);
const fileName = `${hallChoosen.hallName}.pdf`;
pdf.save(fileName);
handleClose();
}
} catch (e) {
handleClose();
} finally {
ShowDialogAgain();
}};
Details on the Situation:
Device Disparities: The PDF output from Html2Canvas varies significantly between devices, suggesting potential rendering inconsistencies due to differing screen resolutions or device-specific factors. Concerns regarding Uniformity: Despite appearing satisfactory on the developer's laptop, unexpected scale styles and variations occur on other devices such as phones or diverse laptops. Potential Cause: The inconsistency likely arises from disparities in screen resolution or rendering mechanisms among distinct devices.
Steps Taken: I endeavored to generate PDF images using Html2Canvas within a React application. The code snippet above utilizes Html2Canvas to convert div content into a base64 string and subsequently captures it in a PDF file. I ensured the PDF format was set to A4 size and managed image dimensions appropriately.
Anticipations: I expected the produced PDFs to display consistent designs across varied devices. Specifically, I anticipated uniform layout and scale regardless of the rendering device. The satisfactory outcome on my laptop led me to believe in the correctness of the code implementation.
Actual Findings: Nevertheless, testing on different devices revealed substantial disparities in PDF outputs. Scale styles and layouts differed considerably compared to results obtained on my laptop. This variance implies misalignment in PDF images across devices, possibly due to dissimilar screen resolutions or other device-related factors.
Seeking Support: I am in need of guidance on ensuring consistent PDF output across different devices when employing Html2Canvas for conversions. Your insights or recommendations on resolving this issue would be highly valued.
Thank you for your anticipated assistance.