TrackView handles its own special XML attributes via virtual functions

src/Track.cpp

@@ -1191,9 +1191,10 @@ void Track::WriteCommonXMLAttributes(
       xmlFile.WriteAttr(wxT("name"), GetName());
       xmlFile.WriteAttr(wxT("isSelected"), this->GetSelected());
    }
-   auto &view = TrackView::Get( *this );
+   if ( mpView )
-   xmlFile.WriteAttr(wxT("height"), view.GetActualHeight());
+      mpView->WriteXMLAttributes( xmlFile );
-   xmlFile.WriteAttr(wxT("minimized"), view.GetMinimized());
+   if ( mpControls )
+      mpControls->WriteXMLAttributes( xmlFile );
 }
 
 // Return true iff the attribute is recognized.
@@ -1201,21 +1202,15 @@ bool Track::HandleCommonXMLAttribute(const wxChar *attr, const wxChar *value)
 {
    long nValue = -1;
    wxString strValue( value );
-   if (!wxStrcmp(attr, wxT("name")) &&
+   if ( mpView && mpView->HandleXMLAttribute( attr, value ) )
+      ;
+   else if ( mpControls && mpControls->HandleXMLAttribute( attr, value ) )
+      ;
+   else if (!wxStrcmp(attr, wxT("name")) &&
       XMLValueChecker::IsGoodString(strValue)) {
       SetName( strValue );
       return true;
    }
-   else if (!wxStrcmp(attr, wxT("height")) &&
-         XMLValueChecker::IsGoodInt(strValue) && strValue.ToLong(&nValue)) {
-      TrackView::Get( *this ).SetHeight(nValue);
-      return true;
-   }
-   else if (!wxStrcmp(attr, wxT("minimized")) &&
-         XMLValueChecker::IsGoodInt(strValue) && strValue.ToLong(&nValue)) {
-      TrackView::Get( *this ).SetMinimized(nValue != 0);
-      return true;
-   }
    else if (!wxStrcmp(attr, wxT("isSelected")) &&
          XMLValueChecker::IsGoodInt(strValue) && strValue.ToLong(&nValue)) {
       this->SetSelected(nValue != 0);

src/tracks/ui/CommonTrackPanelCell.cpp

@@ -66,3 +66,12 @@ std::shared_ptr<Track> CommonTrackCell::DoFindTrack()
 {
    return mwTrack.lock();
 }
+
+void CommonTrackCell::WriteXMLAttributes( XMLWriter & ) const
+{
+}
+
+bool CommonTrackCell::HandleXMLAttribute( const wxChar *, const wxChar * )
+{
+   return false;
+}

src/tracks/ui/CommonTrackPanelCell.h

@@ -19,6 +19,7 @@ Paul Licameli split from TrackPanel.cpp
 #include <functional>
 
 class Track;
+class XMLWriter;
 
 class AUDACITY_DLL_API CommonTrackPanelCell /* not final */
    : public TrackPanelCell
@@ -65,6 +66,12 @@ public:
 
    virtual void Reparent( const std::shared_ptr<Track> &parent );
 
+   // default does nothing
+   virtual void WriteXMLAttributes( XMLWriter & ) const;
+
+   // default recognizes no attributes, and returns false
+   virtual bool HandleXMLAttribute( const wxChar *attr, const wxChar *value );
+
 private:
    std::weak_ptr< Track > mwTrack;
 };

src/tracks/ui/TrackView.cpp

@@ -16,6 +16,8 @@ Paul Licameli split from TrackPanel.cpp
 
 #include "../../ClientData.h"
 #include "../../Project.h"
+#include "../../xml/XMLTagHandler.h"
+#include "../../xml/XMLWriter.h"
 
 TrackView::~TrackView()
 {
@@ -74,6 +76,30 @@ void TrackView::SetMinimized(bool isMinimized)
       leader->AdjustPositions();
 }
 
+void TrackView::WriteXMLAttributes( XMLWriter &xmlFile ) const
+{
+   xmlFile.WriteAttr(wxT("height"), GetActualHeight());
+   xmlFile.WriteAttr(wxT("minimized"), GetMinimized());
+}
+
+bool TrackView::HandleXMLAttribute( const wxChar *attr, const wxChar *value )
+{
+   wxString strValue;
+   long nValue;
+   if (!wxStrcmp(attr, wxT("height")) &&
+         XMLValueChecker::IsGoodInt(strValue) && strValue.ToLong(&nValue)) {
+      SetHeight(nValue);
+      return true;
+   }
+   else if (!wxStrcmp(attr, wxT("minimized")) &&
+         XMLValueChecker::IsGoodInt(strValue) && strValue.ToLong(&nValue)) {
+      SetMinimized(nValue != 0);
+      return true;
+   }
+   else
+      return false;
+}
+
 void TrackView::DoSetMinimized(bool isMinimized)
 {
    mMinimized = isMinimized;

src/tracks/ui/TrackView.h

@@ -69,6 +69,9 @@ public:
    std::shared_ptr<TrackPanelCell> GetResizer();
    std::shared_ptr<const TrackPanelCell> GetResizer() const;
 
+   void WriteXMLAttributes( XMLWriter & ) const override;
+   bool HandleXMLAttribute( const wxChar *attr, const wxChar *value ) override;
+
 protected:
    virtual void DoSetMinimized( bool isMinimized );