toMap method
Implementation
Map<String, dynamic> toMap() {
final map = <String, dynamic>{
'type': typeName,
'rect': rect.toList(),
'xref': xref,
};
if (content != null) map['content'] = content;
if (title != null) map['title'] = title;
if (color != null) map['color'] = color;
if (opacity != null) map['opacity'] = opacity;
return map;
}