X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/4a99d5975088e9c3cf05b3d4d9889bd9b70ea75d..ca77701441e39245dcbfce903049e76f166979e5:/include/wx/gtk/private/event.h?ds=sidebyside

diff --git a/include/wx/gtk/private/event.h b/include/wx/gtk/private/event.h
index 1b23254045..7c1254fea8 100644
--- a/include/wx/gtk/private/event.h
+++ b/include/wx/gtk/private/event.h
@@ -11,6 +11,29 @@
 #ifndef _GTK_PRIVATE_EVENT_H_
 #define _GTK_PRIVATE_EVENT_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
+
 namespace wxGTKImpl
 {