comparison layer/SingleColourLayer.h @ 316:c0b9eec70639

* Make XmlExportable::toXml the function that is universally overridden (and
  pure virtual) instead of toXmlString.  Tidies up some classes, notably the
  model classes, significantly.  Closes #1794561.

     virtual QString getPropertyValueLabel(const PropertyName &,
 					  int value) const;
     virtual RangeMapper *getNewPropertyRangeMapper(const PropertyName &) const;
     virtual void setProperty(const PropertyName &, int value);
 
-    virtual QString toXmlString(QString indent = "",
-				QString extraAttributes = "") const;
+    virtual void toXml(QTextStream &stream, QString indent = "",
+                       QString extraAttributes = "") const;
 
     virtual void setProperties(const QXmlAttributes &attributes);
 
     virtual void setDefaultColourFor(View *v);