SizeField
SizeField(double size);
virtual ~SizeField();
SizeField::SizeField(double size)
SizeField::~SizeField()
SizeField::SetSize(double size)
SizeField::CreateString() const
SizeField* sizeField1 = dynamic_cast<SizeField*>(field1);
SizeField* sizeField2 = dynamic_cast<SizeField*>(field2);
SizeField* existingSizeField = static_cast<SizeField*>(GetField(kSizeColumn));
SetField(new SizeField(updatedSize), kSizeColumn);