Define InvisibleTemporaryProject

src/ProjectFileIO.cpp

@@ -2401,3 +2401,25 @@ int ProjectFileIO::get_varint(const unsigned char *ptr, int64_t *out)
 
    return 9;
 }
+
+InvisibleTemporaryProject::InvisibleTemporaryProject()
+   : mpProject{ std::make_shared< AudacityProject >() }
+{
+}
+
+InvisibleTemporaryProject::~InvisibleTemporaryProject()
+{
+   auto &projectFileIO = ProjectFileIO::Get( Project() );
+   projectFileIO.SetBypass();
+   auto &tracks = TrackList::Get( Project() );
+   tracks.Clear();
+
+   // Consume some delayed track list related events before destroying the
+   // temporary project
+   try { wxTheApp->Yield(); } catch(...) {}
+
+   // Destroy the project and yield again to let delayed window deletions happen
+   projectFileIO.CloseProject();
+   mpProject.reset();
+   try { wxTheApp->Yield(); } catch(...) {}
+}

src/ProjectFileIO.h

@@ -262,4 +262,18 @@ public:
 wxDECLARE_EXPORTED_EVENT(AUDACITY_DLL_API,
                          EVT_PROJECT_TITLE_CHANGE, wxCommandEvent);
 
+//! Makes a temporary project that doesn't display on the screen
+class InvisibleTemporaryProject
+{
+public:
+   InvisibleTemporaryProject();
+   ~InvisibleTemporaryProject();
+   AudacityProject &Project()
+   {
+      return *mpProject;
+   }
+private:
+   std::shared_ptr<AudacityProject> mpProject;
+};
+
 #endif