toXML method Null safety

@override String toXML()

Convert the Svg structure to XML string

Implementation

@override
String toXML() {
  var xml =
      '<line x1="${roundPixels(x1, unit)}" y1="${roundPixels(y1, unit)}" '
      'x2="${roundPixels(x2, unit)}" y2="${roundPixels(y2, unit)}" '
      '${attributes(id, fill, stroke, strokeWidth, strokeDasharray, style, transform, unit, visibility)} />';
  return xml;
}