Display the global menu bar if the last TLW is hidden in wxOSX

Hiding the last TLW should be enough to show the global menu bar, but this
only happened if it was closed and not just hidden.

Closes #16201.

include/wx/osx/frame.h

@@ -51,6 +51,7 @@ public:
     virtual wxPoint GetClientAreaOrigin() const wxOVERRIDE;
 
     // override some more virtuals
+    virtual bool Show(bool show = true) wxOVERRIDE;
     virtual bool Enable(bool enable = true) wxOVERRIDE;
 
     // event handlers

include/wx/osx/menu.h

@@ -152,6 +152,7 @@ public:
     static void SetAutoWindowMenu( bool enable ) { s_macAutoWindowMenu = enable ; }
     static bool GetAutoWindowMenu() { return s_macAutoWindowMenu ; }
 
+    void MacUninstallMenuBar() ;
     void MacInstallMenuBar() ;
     static wxMenuBar* MacGetInstalledMenuBar() { return s_macInstalledMenuBar ; }
     static void MacSetCommonMenuBar(wxMenuBar* menubar) { s_macCommonMenuBar=menubar; }

src/osx/carbon/frame.cpp

@@ -412,4 +412,17 @@ void wxFrame::PositionBars()
 #endif
 }
 
+bool wxFrame::Show(bool show)
+{
+    if ( !show )
+    {
+#if wxUSE_MENUS
+        if (m_frameMenuBar != NULL)
+        {
+          m_frameMenuBar->MacUninstallMenuBar();
+        }
+#endif
+    }
+    return wxFrameBase::Show(show);
+}
 

src/osx/menu_osx.cpp

@@ -633,11 +633,7 @@ wxMenuBar::~wxMenuBar()
     if (s_macCommonMenuBar == this)
         s_macCommonMenuBar = NULL;
 
-    if (s_macInstalledMenuBar == this)
+    MacUninstallMenuBar();
-    {
-        gs_emptyMenuBar->GetPeer()->MakeRoot();
-        s_macInstalledMenuBar = NULL;
-    }
     wxDELETE( m_rootMenu );
     // apple menu is a submenu, therefore we don't have to delete it
     m_appleMenu = NULL;
@@ -652,6 +648,15 @@ void wxMenuBar::Refresh(bool WXUNUSED(eraseBackground), const wxRect *WXUNUSED(r
     wxCHECK_RET( IsAttached(), wxT("can't refresh unatteched menubar") );
 }
 
+void wxMenuBar::MacUninstallMenuBar()
+{
+  if (s_macInstalledMenuBar == this)
+  {
+    gs_emptyMenuBar->GetPeer()->MakeRoot();
+    s_macInstalledMenuBar = NULL;
+  }
+}
+
 void wxMenuBar::MacInstallMenuBar()
 {
     if ( s_macInstalledMenuBar == this )