Missing alias dialog tracking is non-intrusive in class AudacityProject

src/AudacityApp.cpp

@@ -1005,9 +1005,9 @@ Choose Help > Diagnostics > Check Dependencies to view a list of \
 locations of the missing files."), missingFileName);
 
          // if an old dialog exists, raise it if it is
-         if (offendingProject->GetMissingAliasFileDialog()) {
-            offendingProject->GetMissingAliasFileDialog()->Raise();
-         } else {
+         if ( auto dialog = MissingAliasFilesDialog::Find( *offendingProject ) )
+            dialog->Raise();
+         else {
             MissingAliasFilesDialog::Show(offendingProject.get(), _("Files Missing"),
                                    errorMessage, wxT(""), true);
          }

src/MissingAliasFileDialog.cpp

@@ -14,11 +14,16 @@
 #include "Project.h"
 #include "widgets/ErrorDialog.h"
 
+namespace {
+   using wxDialogRef = wxWeakRef< wxDialog >;
+   std::vector< wxDialogRef > sDialogs;
+}
+
 // special case for alias missing dialog because we keep track of if it exists.
 class MissingAliasFileDialog final : public ErrorDialog
 {
    public:
-   MissingAliasFileDialog(AudacityProject *parent,
+   MissingAliasFileDialog(wxWindow *parent,
       const wxString & dlogTitle,
       const wxString & message,
       const wxString & helpURL,
@@ -27,20 +32,23 @@ class MissingAliasFileDialog final : public ErrorDialog
 };
 
 
-MissingAliasFileDialog::MissingAliasFileDialog(AudacityProject *parent,
+MissingAliasFileDialog::MissingAliasFileDialog(wxWindow *parent,
       const wxString & dlogTitle,
       const wxString & message,
       const wxString & helpURL,
       const bool Close, const bool modal):
 ErrorDialog(parent, dlogTitle, message, helpURL, Close, modal)
 {
-   parent->SetMissingAliasFileDialog(this);
+   sDialogs.push_back( this );
 }
 
 MissingAliasFileDialog::~MissingAliasFileDialog()
 {
-   static_cast<AudacityProject *>(GetParent())
-      ->SetMissingAliasFileDialog( nullptr );
+   auto begin = sDialogs.begin(), end = sDialogs.end(),
+      newEnd = std::remove_if( begin, end,
+         [&]( const wxDialogRef &ref ){
+            return ref == this; } );
+   sDialogs.erase( newEnd, end );
 }
 
 namespace MissingAliasFilesDialog {
@@ -82,6 +90,17 @@ namespace MissingAliasFilesDialog {
       // but in practice Destroy() in OnOK does that
    }
    
+   wxDialog *Find( const AudacityProject &project )
+   {
+      auto begin = sDialogs.begin(), end = sDialogs.end(),
+         iter = std::find_if( begin, end,
+            [&]( const wxDialogRef &ref ){
+               return ref && ref->GetParent() == &project; } );
+      if (iter != end)
+         return *iter;
+      return nullptr;
+   }
+
    void Mark(const AliasBlockFile *b)
    {
       Lock lock{ m_LastMissingBlockFileLock };

src/MissingAliasFileDialog.h

@@ -37,6 +37,8 @@ void Show(AudacityProject *parent,
                      const wxString &helpPage,
                      const bool Close = true);
 
+wxDialog *Find( const AudacityProject &project );
+
 }
 
 #endif

src/Project.cpp

@@ -1548,16 +1548,6 @@ void AudacityProject::UpdatePrefs()
    }
 }
 
-void AudacityProject::SetMissingAliasFileDialog(wxDialog *dialog)
-{
-   mMissingAliasFilesWarningDialog = dialog;
-}
-
-wxDialog *AudacityProject::GetMissingAliasFileDialog()
-{
-   return mMissingAliasFilesWarningDialog;
-}
-
 void AudacityProject::RedrawProject(const bool bForceWaveTracks /*= false*/)
 {
    FixScrollbars();

src/Project.h

@@ -341,15 +341,6 @@ public:
    bool GetNormalizeOnLoad() { return mNormalizeOnLoad; } //lda
    void SetNormalizeOnLoad(bool flag) { mNormalizeOnLoad = flag; } //lda
 
-   /** \brief Sets the wxDialog that is being displayed
-     * Used by the custom dialog warning constructor and destructor
-     */
-   void SetMissingAliasFileDialog(wxDialog *dialog);
-
-   /** \brief returns a pointer to the wxDialog if it is displayed, NULL otherwise.
-     */
-   wxDialog *GetMissingAliasFileDialog();
-
    // Timer Record Auto Save/Export Routines
    bool SaveFromTimerRecording(wxFileName fnFile);
    bool ExportFromTimerRecording(wxFileName fnFile, int iFormat, int iSubFormat, int iFilterIndex);
@@ -645,9 +636,6 @@ private:
    Destroy_ptr<FreqWindow> mFreqWindow;
    Destroy_ptr<ContrastDialog> mContrastDialog;
 
-   // dialog for missing alias warnings
-   wxDialog            *mMissingAliasFilesWarningDialog{};
-
    bool mShownOnce{ false };
 
    // Project owned meters