Stop allowing to select the language in the internat sample

Restrict the choice to using the current system locale or not using it,
as setting any other language doesn't, and can't, work under macOS.

samples/internat/internat.cpp

@@ -57,14 +57,13 @@
 class MyApp: public wxApp
 {
 public:
-    MyApp() { m_lang = wxLANGUAGE_UNKNOWN; m_setLocale = true; }
+    MyApp() { m_setLocale = true; }
 
     virtual void OnInitCmdLine(wxCmdLineParser& parser) wxOVERRIDE;
     virtual bool OnCmdLineParsed(wxCmdLineParser& parser) wxOVERRIDE;
     virtual bool OnInit() wxOVERRIDE;
 
 protected:
-    wxLanguage m_lang;  // language specified by user
     bool m_setLocale;   // if false, skip setting locale entirely
     wxLocale m_locale;  // locale we'll be using
 };
@@ -120,59 +119,6 @@ enum
     INTERNAT_MACRO_9
 };
 
-// language data
-static const wxLanguage langIds[] =
-{
-    wxLANGUAGE_DEFAULT,
-    wxLANGUAGE_FRENCH,
-    wxLANGUAGE_ITALIAN,
-    wxLANGUAGE_GERMAN,
-    wxLANGUAGE_RUSSIAN,
-    wxLANGUAGE_BULGARIAN,
-    wxLANGUAGE_CZECH,
-    wxLANGUAGE_POLISH,
-    wxLANGUAGE_SWEDISH,
-#if wxUSE_UNICODE || defined(__WXMOTIF__)
-    wxLANGUAGE_JAPANESE,
-#endif
-#if wxUSE_UNICODE
-    wxLANGUAGE_GEORGIAN,
-    wxLANGUAGE_ENGLISH,
-    wxLANGUAGE_ENGLISH_US,
-    wxLANGUAGE_ARABIC,
-    wxLANGUAGE_ARABIC_EGYPT
-#endif
-};
-
-// note that it makes no sense to translate these strings, they are
-// shown before we set the locale anyhow
-const wxString langNames[] =
-{
-    "System default",
-    "French",
-    "Italian",
-    "German",
-    "Russian",
-    "Bulgarian",
-    "Czech",
-    "Polish",
-    "Swedish",
-#if wxUSE_UNICODE || defined(__WXMOTIF__)
-    "Japanese",
-#endif
-#if wxUSE_UNICODE
-    "Georgian",
-    "English",
-    "English (U.S.)",
-    "Arabic",
-    "Arabic (Egypt)"
-#endif
-};
-
-// the arrays must be in sync
-wxCOMPILE_TIME_ASSERT( WXSIZEOF(langNames) == WXSIZEOF(langIds),
-                       LangArraysMismatch );
-
 // ----------------------------------------------------------------------------
 // wxWidgets macros
 // ----------------------------------------------------------------------------
@@ -213,10 +159,6 @@ void MyApp::OnInitCmdLine(wxCmdLineParser& parser)
     parser.AddSwitch("n", OPTION_NO_LOCALE,
                      _("skip setting locale on startup"));
 
-    parser.AddParam(_("locale"),
-                    wxCMD_LINE_VAL_STRING,
-                    wxCMD_LINE_PARAM_OPTIONAL);
-
     wxApp::OnInitCmdLine(parser);
 }
 
@@ -230,33 +172,6 @@ bool MyApp::OnCmdLineParsed(wxCmdLineParser& parser)
         m_setLocale = false;
     }
 
-    if ( parser.GetParamCount() )
-    {
-        if ( !m_setLocale )
-        {
-            wxLogError("Locale parameter ignored when %s option is used.",
-                       OPTION_NO_LOCALE);
-            return false;
-        }
-
-        const wxString loc = parser.GetParam();
-        if ( loc.empty() )
-        {
-            m_lang = wxLANGUAGE_DEFAULT;
-        }
-        else
-        {
-            const wxLanguageInfo * const lang = wxLocale::FindLanguageInfo(loc);
-            if ( !lang )
-            {
-                wxLogError(_("Locale \"%s\" is unknown."), loc);
-                return false;
-            }
-
-            m_lang = static_cast<wxLanguage>(lang->Language);
-        }
-    }
-
     return true;
 }
 
@@ -266,36 +181,39 @@ bool MyApp::OnInit()
     if ( !wxApp::OnInit() )
         return false;
 
-    if ( m_setLocale )
+    // For demonstration purposes only, ask the user if they want to run the
-    {
+    // program using the current system language. In real programs, we would do
-        if ( m_lang == wxLANGUAGE_UNKNOWN )
+    // it unconditionally for localized programs -- or never do it at all for
-        {
+    // the other ones.
-            int lng = wxGetSingleChoiceIndex
+    const wxLanguageInfo* const
-                      (
+        langInfo = wxLocale::GetLanguageInfo(wxLANGUAGE_DEFAULT);
-                        "Please choose a language or cancel to skip changing it:",
+    const wxString
-                        "Language",
+        langDesc = langInfo ? langInfo->Description
-                        WXSIZEOF(langNames),
+                            : "the default system locale";
-                        langNames
+    if ( m_setLocale &&
-                      );
+             wxMessageBox
-            if ( lng == -1 )
+             (
-                m_setLocale = false;
+                wxString::Format
-            else
+                (
-                m_lang = langIds[lng];
+                    "Would you like to use the program in %s?",
-        }
+                    langDesc
-    }
+                ),
-
+                "wxWidgets i18n (internat) sample",
-    if ( m_setLocale )
+                wxYES_NO
+             ) == wxYES )
     {
         // don't use wxLOCALE_LOAD_DEFAULT flag so that Init() doesn't return
         // false just because it failed to load wxstd catalog
-        if ( !m_locale.Init(m_lang, wxLOCALE_DONT_LOAD_DEFAULT) )
+        if ( !m_locale.Init(wxLANGUAGE_DEFAULT, wxLOCALE_DONT_LOAD_DEFAULT) )
         {
-            wxLogWarning(_("This language is not supported by the system."));
+            wxLogWarning("Failed to initialize the default system locale.");
-
-            // continue nevertheless
         }
     }
 
+
+    // Independently of whether we set the locale or not, we always load the
+    // translations (for the default system language) here.
+
     // normally this wouldn't be necessary as the catalog files would be found
     // in the default locations, but when the program is not installed the
     // catalogs are in the build directory where we wouldn't find them by
@@ -306,12 +224,11 @@ bool MyApp::OnInit()
     wxTranslations* const trans = new wxTranslations();
     wxTranslations::Set(trans);
 
-    // Initialize the catalogs we'll be using
+    // Initialize the catalogs we'll be using.
-    const wxLanguageInfo* pInfo = wxLocale::GetLanguageInfo(m_lang);
     if ( !trans->AddCatalog("internat") )
     {
-        wxLogError(_("Couldn't find/load the 'internat' catalog for locale '%s'."),
+        wxLogError(_("Couldn't find/load 'internat' catalog for %s."),
-                   pInfo ? pInfo->GetLocaleName() : _("unknown"));
+                   langDesc);
     }
 
     // Now try to add wxstd.mo so that loading "NOTEXIST.ING" file will produce