Added white background rectangle to SVG XML code output, in all language versions.

cpp/QrCode.cpp

@@ -171,6 +171,7 @@ std::string qrcodegen::QrCode::toSvgString(int border) const {
 	sb << "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n";
 	sb << "<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 ";
 	sb << (size + border * 2) << " " << (size + border * 2) << "\">\n";
+	sb << "\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\" stroke-width=\"0\"/>\n"
 	sb << "\t<path d=\"";
 	bool head = true;
 	for (int y = -border; y < size + border; y++) {

java/io/nayuki/qrcodegen/QrCode.java

@@ -310,6 +310,7 @@ public final class QrCode {
 		sb.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
 		sb.append("<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n");
 		sb.append(String.format("<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 %1$d %1$d\">\n", size + border * 2));
+		sb.append("\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\" stroke-width=\"0\"/>\n");
 		sb.append("\t<path d=\"");
 		boolean head = true;
 		for (int y = -border; y < size + border; y++) {

javascript/qrcodegen.js

@@ -198,6 +198,7 @@ var qrcodegen = new function() {
 			var result = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
 			result += "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n";
 			result += "<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 " + (size + border * 2) + " " + (size + border * 2) + "\">\n";
+			result += "\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\" stroke-width=\"0\"/>\n";
 			result += "\t<path d=\"";
 			var head = true;
 			for (var y = -border; y < size + border; y++) {

python/qrcodegen.py

@@ -239,6 +239,7 @@ class QrCode(object):
 		return """<?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
 <svg xmlns="http://www.w3.org/2000/svg" version="1.1" viewBox="0 0 {0} {0}">
+	<rect width="100%" height="100%" fill="#FFFFFF" stroke-width="0"/>
 	<path d="{1}" fill="#000000" stroke-width="0"/>
 </svg>
 """.format(self.size + border * 2, " ".join(parts))