Define and use TranslatableStringArray. This lets you define "listeners"...

... for language changes, without inserting extra code to send the
notifications.

src/AudacityApp.cpp

@@ -22,6 +22,7 @@ It handles initialization and termination by subclassing wxApp.
 #endif
 
 #include "Audacity.h" // This should always be included first
+#include "TranslatableStringArray.h"
 
 #include <wx/defs.h>
 #include <wx/app.h>
@@ -93,8 +94,6 @@ It handles initialization and termination by subclassing wxApp.
 #include "commands/Keyboard.h"
 #include "widgets/ErrorDialog.h"
 #include "prefs/DirectoriesPrefs.h"
-#include "prefs/SpectrogramSettings.h"
-#include "prefs/WaveformSettings.h"
 
 //temporarilly commented out till it is added to all projects
 //#include "Profiler.h"
@@ -234,6 +233,7 @@ It handles initialization and termination by subclassing wxApp.
 ////////////////////////////////////////////////////////////
 
 DEFINE_EVENT_TYPE(EVT_OPEN_AUDIO_FILE);
+DEFINE_EVENT_TYPE(EVT_LANGUAGE_CHANGE);
 
 #ifdef __WXGTK__
 static void wxOnAssert(const wxChar *fileName, int lineNumber, const wxChar *msg)
@@ -1039,9 +1039,11 @@ void AudacityApp::InitLang( const wxString & lang )
 
    Internat::Init();
 
-   // Some static arrays unconnected with any project want to be informed of language changes.
-   SpectrogramSettings::InvalidateNames();
-   WaveformSettings::InvalidateNames();
+   // Notify listeners of language changes
+   {
+      wxCommandEvent evt(EVT_LANGUAGE_CHANGE);
+      ProcessEvent(evt);
+   }
 }
 
 void AudacityApp::OnFatalException()

src/Makefile.am

@@ -231,6 +231,7 @@ audacity_SOURCES = \
 	TrackPanel.h \
 	TrackPanelAx.cpp \
 	TrackPanelAx.h \
+	TranslatableStringArray.h \
 	UndoManager.cpp \
 	UndoManager.h \
 	ViewInfo.cpp \

src/TranslatableStringArray.h

@@ -0,0 +1,80 @@
+/**********************************************************************
+
+Audacity: A Digital Audio Editor
+
+TranslatableStringArray.h
+
+Paul Licameli
+
+**********************************************************************/
+
+#ifndef __AUDACITY_TRANSLATABLE_STRING_ARRAY__
+#define __AUDACITY_TRANSLATABLE_STRING_ARRAY__
+
+#include <vector>
+#include <wx/app.h>
+#include <wx/event.h>
+
+class wxArrayString;
+
+DECLARE_EXPORTED_EVENT_TYPE(AUDACITY_DLL_API, EVT_LANGUAGE_CHANGE, -1);
+
+/*
+This class can maintain a static table containing user visible strings that updates
+itself properly when the language is changed in Preferences.
+
+Typical usage is to define a derived class, override Populate(), and then
+make a singleton instance of the class.
+
+Populate() is called only as needed to fill the table on demand the first
+time it is used after application startup or language change.
+*/
+
+template<typename ArrayType> class TranslatableArray
+   : public wxEvtHandler
+{
+public:
+
+   TranslatableArray()
+   {
+      if (wxTheApp)
+         wxTheApp->Connect(EVT_LANGUAGE_CHANGE,
+            wxCommandEventHandler(TranslatableArray::Invalidate),
+            NULL,
+            this);
+   }
+
+   ~TranslatableArray()
+   {
+      if (wxTheApp)
+         wxTheApp->Disconnect(EVT_LANGUAGE_CHANGE,
+            wxCommandEventHandler(TranslatableArray::Invalidate),
+            NULL,
+            this);
+   }
+
+   const ArrayType& Get()
+   {
+      if (mContents.empty())
+         Populate();
+      return mContents;
+   }
+
+protected:
+   // Override this function to fill in mContents,
+   // typically by lines like
+   // mContents.push_back(_("Translate me"));
+   virtual void Populate() = 0;
+
+   void Invalidate(wxCommandEvent &evt)
+   {
+      mContents.clear();
+      evt.Skip();
+   }
+
+   ArrayType mContents;
+};
+
+typedef TranslatableArray<wxArrayString> TranslatableStringArray;
+
+#endif

src/prefs/SpectrogramSettings.cpp

@@ -16,6 +16,7 @@ Paul Licameli
 #include "../Audacity.h"
 #include "SpectrogramSettings.h"
 #include "../NumberScale.h"
+#include "../TranslatableStringArray.h"
 
 #include <algorithm>
 #include <wx/msgdlg.h>
@@ -142,65 +143,49 @@ SpectrogramSettings& SpectrogramSettings::defaults()
    return instance;
 }
 
-namespace
-{
-   wxArrayString &scaleNamesArray()
-   {
-      static wxArrayString theArray;
-      return theArray;
-   }
-
-   wxArrayString &algorithmNamesArray()
-   {
-      static wxArrayString theArray;
-      return theArray;
-   }
-}
-
-//static
-void SpectrogramSettings::InvalidateNames()
-{
-   scaleNamesArray().Clear();
-   algorithmNamesArray().Clear();
-}
-
 //static
 const wxArrayString &SpectrogramSettings::GetScaleNames()
 {
-   wxArrayString &theArray = scaleNamesArray();
+   class ScaleNamesArray : public TranslatableStringArray
+   {
+      virtual void Populate()
+      {
+         // Keep in correspondence with enum SpectrogramSettings::ScaleType:
+         mContents.Add(_("Linear"));
+         mContents.Add(_("Logarithmic"));
+         /* i18n-hint: The name of a frequency scale in psychoacoustics */
+         mContents.Add(_("Mel"));
+         /* i18n-hint: The name of a frequency scale in psychoacoustics, named for Heinrich Barkhausen */
+         mContents.Add(_("Bark"));
+         /* i18n-hint: The name of a frequency scale in psychoacoustics, abbreviates Equivalent Rectangular Bandwidth */
+         mContents.Add(_("ERBS"));
+         /* i18n-hint: A mathematical formula where f stands for frequency */
+         mContents.Add(_("1 / f"));
+      }
+   };
 
-   if (theArray.IsEmpty()) {
-      // Keep in correspondence with enum SpectrogramSettings::ScaleType:
-      theArray.Add(_("Linear"));
-      theArray.Add(_("Logarithmic"));
-      /* i18n-hint: The name of a frequency scale in psychoacoustics */
-      theArray.Add(_("Mel"));
-      /* i18n-hint: The name of a frequency scale in psychoacoustics, named for Heinrich Barkhausen */
-      theArray.Add(_("Bark"));
-      /* i18n-hint: The name of a frequency scale in psychoacoustics, abbreviates Equivalent Rectangular Bandwidth */
-      theArray.Add(_("ERBS"));
-      /* i18n-hint: A mathematical formula where f stands for frequency */
-      theArray.Add(_("1 / f"));
-   }
-
-   return theArray;
+   static ScaleNamesArray theArray;
+   return theArray.Get();
 }
 
 //static
 const wxArrayString &SpectrogramSettings::GetAlgorithmNames()
 {
-   wxArrayString &theArray = algorithmNamesArray();
+   class AlgorithmNamesArray : public TranslatableStringArray
+   {
+      virtual void Populate()
+      {
+         // Keep in correspondence with enum SpectrogramSettings::Algorithm:
+         mContents.Add(_("Frequencies"));
+         /* i18n-hint: the Reassignment algorithm for spectrograms */
+         mContents.Add(_("Reassignment"));
+         /* i18n-hint: EAC abbreviates "Enhanced Autocorrelation" */
+         mContents.Add(_("Pitch (EAC)"));
+      }
+   };
 
-   if (theArray.IsEmpty()) {
-      // Keep in correspondence with enum SpectrogramSettings::Algorithm:
-      theArray.Add(_("Frequencies"));
-      /* i18n-hint: the Reassignment algorithm for spectrograms */
-      theArray.Add(_("Reassignment"));
-      /* i18n-hint: EAC abbreviates "Enhanced Autocorrelation" */
-      theArray.Add(_("Pitch (EAC)"));
-   }
-
-   return theArray;
+   static AlgorithmNamesArray theArray;
+   return theArray.Get();
 }
 
 bool SpectrogramSettings::Validate(bool quiet)

src/prefs/SpectrogramSettings.h

@@ -62,7 +62,6 @@ public:
       stNumScaleTypes,
    };
 
-   static void InvalidateNames(); // in case of language change
    static const wxArrayString &GetScaleNames();
    static const wxArrayString &GetAlgorithmNames();
 

src/prefs/WaveformSettings.cpp

@@ -22,6 +22,7 @@ Paul Licameli
 #include <wx/intl.h>
 
 #include "../Prefs.h"
+#include "../TranslatableStringArray.h"
 
 WaveformSettings::Globals::Globals()
 {
@@ -145,33 +146,21 @@ void WaveformSettings::NextHigherDBRange()
    ConvertToActualDBRange();
 }
 
-namespace
-{
-   wxArrayString &scaleNamesArray()
-   {
-      static wxArrayString theArray;
-      return theArray;
-   }
-}
-
-//static
-void WaveformSettings::InvalidateNames()
-{
-   scaleNamesArray().Clear();
-}
-
 //static
 const wxArrayString &WaveformSettings::GetScaleNames()
 {
-   wxArrayString &theArray = scaleNamesArray();
+   class ScaleNamesArray : public TranslatableStringArray
+   {
+      virtual void Populate()
+      {
+         // Keep in correspondence with enum WaveTrack::WaveTrackDisplay:
+         mContents.Add(_("Linear"));
+         mContents.Add(_("Logarithmic"));
+      }
+   };
 
-   if (theArray.IsEmpty()) {
-      // Keep in correspondence with enum WaveTrack::WaveTrackDisplay:
-      theArray.Add(_("Linear"));
-      theArray.Add(_("Logarithmic"));
-   }
-
-   return theArray;
+   static ScaleNamesArray theArray;
+   return theArray.Get();
 }
 
 WaveformSettings::~WaveformSettings()

src/prefs/WaveformSettings.h

@@ -57,7 +57,6 @@ public:
       stNumScaleTypes,
    };
 
-   static void InvalidateNames(); // in case of language change
    static const wxArrayString &GetScaleNames();
 
    ScaleType scaleType;

win/Projects/Audacity/Audacity.vcxproj

@@ -434,6 +434,7 @@
     <ClInclude Include="..\..\..\src\SseMathFuncs.h" />
     <ClInclude Include="..\..\..\src\toolbars\SpectralSelectionBar.h" />
     <ClInclude Include="..\..\..\src\toolbars\SpectralSelectionBarListener.h" />
+    <ClInclude Include="..\..\..\src\TranslatableStringArray.h" />
     <ClInclude Include="..\..\..\src\WaveTrackLocation.h" />
     <ClInclude Include="..\..\..\src\widgets\HelpSystem.h" />
     <ClInclude Include="..\..\..\src\widgets\NumericTextCtrl.h" />

win/Projects/Audacity/Audacity.vcxproj.filters

@@ -1708,6 +1708,9 @@
     <ClInclude Include="..\..\..\src\effects\VST\VSTControlMSW.h">
       <Filter>src\effects\VST</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\src\TranslatableStringArray.h">
+      <Filter>src</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Image Include="..\..\audacity.ico">