Use an event so that ProjectSettings.cpp does not need TrackPanel.h

src/ProjectSettings.cpp

@@ -13,9 +13,19 @@ Paul Licameli split from AudacityProject.cpp
 #include "AudioIO.h"
 #include "Project.h"
 #include "Snap.h"
-#include "TrackPanel.h"
 #include "prefs/QualityPrefs.h"
 
+wxDEFINE_EVENT(EVT_PROJECT_SETTINGS_CHANGE, wxCommandEvent);
+
+namespace {
+   void Notify( AudacityProject &project, ProjectSettings::EventCode code )
+   {
+      wxCommandEvent e{ EVT_PROJECT_SETTINGS_CHANGE };
+      e.SetInt( static_cast<int>( code ) );
+      project.GetEventHandler()->ProcessEvent( e );
+   }
+}
+
 static const AudacityProject::AttachedObjects::RegisteredFactory
 sProjectSettingsKey{
   []( AudacityProject &project ){
@@ -157,7 +167,7 @@ void ProjectSettings::SetSyncLock(bool flag)
    auto &project = mProject;
    if (flag != mIsSyncLocked) {
       mIsSyncLocked = flag;
-      TrackPanel::Get( project ).Refresh(false);
+      Notify( project, ChangedSyncLock );
    }
 }
 

src/ProjectSettings.h

@@ -11,11 +11,17 @@ Paul Licameli split from AudacityProject.h
 #ifndef __AUDACITY_PROJECT_SETTINGS__
 #define __AUDACITY_PROJECT_SETTINGS__
 
+#include <wx/event.h> // to declare custom event type
+
 #include "ClientData.h" // to inherit
 #include "Prefs.h" // to inherit
 
 class AudacityProject;
 
+// Sent to the project when certain settings change
+wxDECLARE_EXPORTED_EVENT(AUDACITY_DLL_API,
+   EVT_PROJECT_SETTINGS_CHANGE, wxCommandEvent);
+
 ///\brief Holds various per-project settings values, including the sample rate,
 /// and sends events to the project when certain values change
 class ProjectSettings final
@@ -26,6 +32,11 @@ public:
    static ProjectSettings &Get( AudacityProject &project );
    static const ProjectSettings &Get( const AudacityProject &project );
    
+   // Values retrievable from GetInt() of the event for settings change
+   enum EventCode : int {
+      ChangedSyncLock,
+   };
+
    ProjectSettings( AudacityProject &project );
 
    sampleFormat GetDefaultFormat() const { return mDefaultFormat; }

src/TrackPanel.cpp

@@ -70,6 +70,7 @@ is time to refresh some aspect of the screen.
 #include "AdornedRulerPanel.h"
 #include "KeyboardCapture.h"
 #include "Project.h"
+#include "ProjectSettings.h"
 #include "TrackPanelMouseEvent.h"
 #include "TrackPanelResizeHandle.h"
 //#define DEBUG_DRAW_TIMING 1
@@ -316,8 +317,11 @@ TrackPanel::TrackPanel(wxWindow * parent, wxWindowID id,
                      &TrackPanel::OnPlayback,
                      this);
 
-   GetProject()->Bind(EVT_ODTASK_UPDATE, &TrackPanel::OnODTask, this);
-   GetProject()->Bind(EVT_ODTASK_COMPLETE, &TrackPanel::OnODTask, this);
+   auto theProject = GetProject();
+   theProject->Bind(EVT_ODTASK_UPDATE, &TrackPanel::OnODTask, this);
+   theProject->Bind(EVT_ODTASK_COMPLETE, &TrackPanel::OnODTask, this);
+   theProject->Bind(
+      EVT_PROJECT_SETTINGS_CHANGE, &TrackPanel::OnProjectSettingsChange, this);
 
    UpdatePrefs();
 }
@@ -530,6 +534,18 @@ void TrackPanel::OnODTask(wxCommandEvent & WXUNUSED(event))
    Refresh(false);
 }
 
+void TrackPanel::OnProjectSettingsChange( wxCommandEvent &event )
+{
+   event.Skip();
+   switch ( static_cast<ProjectSettings::EventCode>( event.GetInt() ) ) {
+   case ProjectSettings::ChangedSyncLock:
+      Refresh(false);
+      break;
+   default:
+      break;
+   }
+}
+
 double TrackPanel::GetScreenEndTime() const
 {
    int width;

src/TrackPanel.h

@@ -289,6 +289,7 @@ class AUDACITY_DLL_API TrackPanel final
    void OnIdle(wxIdleEvent & event);
    void OnTimer(wxTimerEvent& event);
    void OnODTask(wxCommandEvent &event);
+   void OnProjectSettingsChange(wxCommandEvent &event);
 
    int GetLeftOffset() const { return GetLabelWidth() + 1;}