Context menu handling is also in CellularPanel

src/Track.h

@@ -165,6 +165,10 @@ class AUDACITY_DLL_API Track /* not final */
       (const TrackPanelMouseState &, const AudacityProject *pProject)
       final override;
 
+   // Delegates the handling to the related TCP cell
+   std::shared_ptr<TrackPanelCell> ContextMenuDelegate() override
+      { return GetTrackControl(); }
+
  public:
 
    // Rather override this for subclasses:

src/TrackPanel.cpp

@@ -263,6 +263,7 @@ BEGIN_EVENT_TABLE(CellularPanel, OverlayPanel)
     EVT_CHAR(CellularPanel::OnChar)
     EVT_SET_FOCUS(CellularPanel::OnSetFocus)
     EVT_KILL_FOCUS(CellularPanel::OnKillFocus)
+    EVT_CONTEXT_MENU(CellularPanel::OnContextMenu)
 END_EVENT_TABLE()
 
 BEGIN_EVENT_TABLE(TrackPanel, CellularPanel)
@@ -270,7 +271,6 @@ BEGIN_EVENT_TABLE(TrackPanel, CellularPanel)
     EVT_KEY_DOWN(TrackPanel::OnKeyDown)
 
     EVT_PAINT(TrackPanel::OnPaint)
-    EVT_CONTEXT_MENU(TrackPanel::OnContextMenu)
 
     EVT_TIMER(wxID_ANY, TrackPanel::OnTimer)
 END_EVENT_TABLE()
@@ -1167,9 +1167,9 @@ void TrackPanel::OnTrackListDeletion(wxCommandEvent & e)
    e.Skip();
 }
 
-void TrackPanel::OnContextMenu(wxContextMenuEvent & WXUNUSED(event))
+void CellularPanel::OnContextMenu(wxContextMenuEvent & WXUNUSED(event))
 {
-   OnTrackMenu();
+   DoContextMenu();
 }
 
 struct TrackInfo::TCPLine {
@@ -2625,17 +2625,27 @@ void TrackPanel::ScrollIntoView(int x)
 
 void TrackPanel::OnTrackMenu(Track *t)
 {
-   if(!t) {
-      t = GetFocusedTrack();
-      if(!t)
+   CellularPanel::DoContextMenu( t );
+}
+
+void CellularPanel::DoContextMenu( TrackPanelCell *pCell )
+{
+   if( !pCell ) {
+      pCell = GetFocusedCell();
+      if( !pCell )
          return;
    }
 
-   const auto pCell = t->GetTrackControl();
-   const wxRect rect(FindTrackRect(t, true));
+   const auto delegate = pCell->ContextMenuDelegate();
+   if (!delegate)
+      return;
+
+   auto rect = FindRect( *delegate );
    const UIHandle::Result refreshResult =
-      pCell->DoContextMenu(rect, this, NULL);
-   ProcessUIHandleResult(t, t, refreshResult);
+      delegate->DoContextMenu(rect, this, NULL);
+
+   // To do: use safer shared_ptr to pCell
+   ProcessUIHandleResult(pCell, pCell, refreshResult);
 }
 
 Track * TrackPanel::GetFirstSelectedTrack()

src/TrackPanel.h

@@ -305,6 +305,7 @@ protected:
       mTarget = 0;
       mMouseOverUpdateFlags = 0;
    }
+   void DoContextMenu( TrackPanelCell *pCell = nullptr );
    
 private:
    bool HasRotation();
@@ -320,6 +321,8 @@ private:
    void OnSetFocus(wxFocusEvent & event);
    void OnKillFocus(wxFocusEvent & event);
 
+   void OnContextMenu(wxContextMenuEvent & event);
+
    void HandleInterruptedDrag();
    void Uncapture( wxMouseState *pState = nullptr );
    bool HandleEscapeKey(bool down);
@@ -383,8 +386,6 @@ class AUDACITY_DLL_API TrackPanel final : public CellularPanel {
    void OnMouseEvent(wxMouseEvent & event);
    void OnKeyDown(wxKeyEvent & event);
 
-   void OnContextMenu(wxContextMenuEvent & event);
-
    void OnPlayback(wxCommandEvent &);
    void OnTrackListResizing(wxCommandEvent & event);
    void OnTrackListDeletion(wxCommandEvent & event);

src/TrackPanelCell.h

@@ -56,6 +56,10 @@ public:
       (const TrackPanelMouseEvent &event,
        AudacityProject *pProject);
 
+   // A cell may delegate context menu handling to another one
+   virtual std::shared_ptr<TrackPanelCell> ContextMenuDelegate()
+      { return {}; }
+
    // The pPosition parameter indicates mouse position but may be NULL
    // Return value is a bitwise OR of RefreshCode values
    // Default implementation does nothing