Fixed detection of Meta key state so that NumLock isn't misdetected as Meta.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@54758 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -117,7 +117,7 @@ All (Unix):
 
 wxMSW:
 
-+ Potentially incompatible change: wxExecute() arguments are now quoted if they
+- Potentially incompatible change: wxExecute() arguments are now quoted if they
   contain spaces and existing quotes are escaped with a backslash. However, to
   preserve compatibility, the argument is unchanged if it is already quoted.
   Notice that this behaviour will change in wxWidgets 3.0 where all arguments
@@ -131,8 +131,10 @@ wxMSW:
 
 wxGTK:
 
-- Fix masking of disabled bitmaps in wxMenuItem and wxStaticBitmap.
+- Fixed masking of disabled bitmaps in wxMenuItem and wxStaticBitmap.
-- Fix generation of events for an initially empty wxDirPickerCtrl.
+- Fixed generation of events for an initially empty wxDirPickerCtrl.
+- Fixed detection of Meta key state so that NumLock isn't misdetected
+  as Meta (requires GTK+ 2.10).
 
 wxMac:
 

src/gtk/window.cpp

@@ -59,6 +59,29 @@
 #include <gdk/gdkkeysyms.h>
 #include <gdk/gdkx.h>
 
+#if !GTK_CHECK_VERSION(2,10,0)
+    // GTK+ can reliably detect Meta key state only since 2.10 when
+    // GDK_META_MASK was introduced -- there wasn't any way to detect it
+    // in older versions. wxGTK used GDK_MOD2_MASK for this purpose, but
+    // GDK_MOD2_MASK is documented as:
+    //
+    //     the fifth modifier key (it depends on the modifier mapping of the X
+    //     server which key is interpreted as this modifier)
+    //
+    // In other words, it isn't guaranteed to map to Meta. This is a real
+    // problem: it is common to map NumLock to it (in fact, it's an exception
+    // if the X server _doesn't_ use it for NumLock).  So the old code caused
+    // wxKeyEvent::MetaDown() to always return true as long as NumLock was on
+    // on many systems, which broke all applications using
+    // wxKeyEvent::GetModifiers() to check modifiers state (see e.g.  here:
+    // http://tinyurl.com/56lsk2).
+    //
+    // Because of this, it's better to not detect Meta key state at all than
+    // to detect it incorrectly. Hence the following #define, which causes
+    // m_metaDown to be always set to false.
+    #define GDK_META_MASK 0
+#endif
+
 //-----------------------------------------------------------------------------
 // documentation on internals
 //-----------------------------------------------------------------------------
@@ -838,7 +861,7 @@ static void wxFillOtherKeyEventFields(wxKeyEvent& event,
     event.m_shiftDown = (gdk_event->state & GDK_SHIFT_MASK) != 0;
     event.m_controlDown = (gdk_event->state & GDK_CONTROL_MASK) != 0;
     event.m_altDown = (gdk_event->state & GDK_MOD1_MASK) != 0;
-    event.m_metaDown = (gdk_event->state & GDK_MOD2_MASK) != 0;
+    event.m_metaDown = (gdk_event->state & GDK_META_MASK) != 0;
     event.m_scanCode = gdk_event->keyval;
     event.m_rawCode = (wxUint32) gdk_event->keyval;
     event.m_rawFlags = 0;
@@ -1281,7 +1304,7 @@ template<typename T> void InitMouseEvent(wxWindowGTK *win,
     event.m_shiftDown = (gdk_event->state & GDK_SHIFT_MASK);
     event.m_controlDown = (gdk_event->state & GDK_CONTROL_MASK);
     event.m_altDown = (gdk_event->state & GDK_MOD1_MASK);
-    event.m_metaDown = (gdk_event->state & GDK_MOD2_MASK);
+    event.m_metaDown = (gdk_event->state & GDK_META_MASK);
     event.m_leftDown = (gdk_event->state & GDK_BUTTON1_MASK);
     event.m_middleDown = (gdk_event->state & GDK_BUTTON2_MASK);
     event.m_rightDown = (gdk_event->state & GDK_BUTTON3_MASK);
@@ -1790,7 +1813,7 @@ window_scroll_event(GtkWidget*, GdkEventScroll* gdk_event, wxWindow* win)
     event.m_shiftDown = (gdk_event->state & GDK_SHIFT_MASK);
     event.m_controlDown = (gdk_event->state & GDK_CONTROL_MASK);
     event.m_altDown = (gdk_event->state & GDK_MOD1_MASK);
-    event.m_metaDown = (gdk_event->state & GDK_MOD2_MASK);
+    event.m_metaDown = (gdk_event->state & GDK_META_MASK);
     event.m_leftDown = (gdk_event->state & GDK_BUTTON1_MASK);
     event.m_middleDown = (gdk_event->state & GDK_BUTTON2_MASK);
     event.m_rightDown = (gdk_event->state & GDK_BUTTON3_MASK);
@@ -2003,7 +2026,7 @@ gtk_window_leave_callback( GtkWidget *widget,
     event.m_shiftDown = (state & GDK_SHIFT_MASK) != 0;
     event.m_controlDown = (state & GDK_CONTROL_MASK) != 0;
     event.m_altDown = (state & GDK_MOD1_MASK) != 0;
-    event.m_metaDown = (state & GDK_MOD2_MASK) != 0;
+    event.m_metaDown = (state & GDK_META_MASK) != 0;
     event.m_leftDown = (state & GDK_BUTTON1_MASK) != 0;
     event.m_middleDown = (state & GDK_BUTTON2_MASK) != 0;
     event.m_rightDown = (state & GDK_BUTTON3_MASK) != 0;
@@ -2289,7 +2312,7 @@ wxMouseState wxGetMouseState()
     ms.SetControlDown(mask & GDK_CONTROL_MASK);
     ms.SetShiftDown(mask & GDK_SHIFT_MASK);
     ms.SetAltDown(mask & GDK_MOD1_MASK);
-    ms.SetMetaDown(mask & GDK_MOD2_MASK);
+    ms.SetMetaDown(mask & GDK_META_MASK);
 
     return ms;
 }