Add WXK_NUMPAD_CENTER to refer to numpad "5" in portable code

This key produces events with different key codes in wxMSW (WXK_CLEAR)
and the other ports (WXK_NUMPAD_BEGIN), so add a new constant to allow
to refer to it under the same name everywhere.

Also generate a key event for it in wxOSX where it previously wasn't
generated at all.

Closes #23478.

Closes #23491.

include/wx/defs.h

@@ -2363,7 +2363,15 @@ enum wxKeyCode
     // These constants are the same as the corresponding GTK keys, so give them
     // the same value, but they are also generated by wxMSW.
     WXK_LAUNCH_APP1 = WXK_LAUNCH_A,
-    WXK_LAUNCH_APP2 = WXK_LAUNCH_B
+    WXK_LAUNCH_APP2 = WXK_LAUNCH_B,
+
+    // This one provides a portable way to refer to the key event generated by
+    // the "5" key on the numpad when Num Lock is off.
+#ifdef __WXMSW__
+    WXK_NUMPAD_CENTER = WXK_CLEAR
+#else
+    WXK_NUMPAD_CENTER = WXK_NUMPAD_BEGIN
+#endif
 };
 
 /* This enum contains bit mask constants used in wxKeyEvent */

interface/wx/defs.h

@@ -924,6 +924,7 @@ enum wxKeyCode
     WXK_RBUTTON,
     WXK_CANCEL,
     WXK_MBUTTON,
+    /// See WXK_NUMPAD_CENTER.
     WXK_CLEAR,
     WXK_SHIFT,
     WXK_ALT,
@@ -1015,6 +1016,7 @@ enum wxKeyCode
     WXK_NUMPAD_PAGEUP,
     WXK_NUMPAD_PAGEDOWN,
     WXK_NUMPAD_END,
+    /// See WXK_NUMPAD_CENTER.
     WXK_NUMPAD_BEGIN,
     WXK_NUMPAD_INSERT,
     WXK_NUMPAD_DELETE,
@@ -1107,7 +1109,19 @@ enum wxKeyCode
     WXK_LAUNCH_C, ///< Available since wxWidgets 3.1.6 and only generated by wxGTK.
     WXK_LAUNCH_D, ///< Available since wxWidgets 3.1.6 and only generated by wxGTK.
     WXK_LAUNCH_E, ///< Available since wxWidgets 3.1.6 and only generated by wxGTK.
-    WXK_LAUNCH_F  ///< Available since wxWidgets 3.1.6 and only generated by wxGTK.
+    WXK_LAUNCH_F, ///< Available since wxWidgets 3.1.6 and only generated by wxGTK.
+
+    /**
+        Key code corresponding to the event produced by the "5" key on the
+        numeric pad when Num Lock is off.
+
+        This constant has the same value as WXK_CLEAR under wxMSW and
+        WXK_NUMPAD_BEGIN in the other ports but using it is preferable in
+        portable code.
+
+        @since 3.3.0
+     */
+    WXK_NUMPAD_CENTER
 };
 
 /**

samples/keyboard/keyboard.cpp

@@ -386,7 +386,7 @@ const char* GetVirtualKeyCodeName(int keycode)
         WXK_(RBUTTON)
         WXK_(CANCEL)
         WXK_(MBUTTON)
-        WXK_(CLEAR)
+        WXK_(NUMPAD_CENTER)
         WXK_(SHIFT)
         WXK_(ALT)
         WXK_(CONTROL)
@@ -464,7 +464,6 @@ const char* GetVirtualKeyCodeName(int keycode)
         WXK_(NUMPAD_PAGEUP)
         WXK_(NUMPAD_PAGEDOWN)
         WXK_(NUMPAD_END)
-        WXK_(NUMPAD_BEGIN)
         WXK_(NUMPAD_INSERT)
         WXK_(NUMPAD_DELETE)
         WXK_(NUMPAD_EQUAL)

src/gtk/window.cpp

@@ -876,7 +876,7 @@ static long wxTranslateKeySymToWXKey(KeySym keysym, bool isChar)
             break;
 
         case GDK_KEY_KP_Begin:
-            key_code = isChar ? WXK_HOME : WXK_NUMPAD_BEGIN;
+            key_code = WXK_NUMPAD_BEGIN;
             break;
 
         case GDK_KEY_KP_Insert:

src/osx/cocoa/window.mm

@@ -311,9 +311,9 @@ long wxOSXTranslateCocoaKey( NSEvent* event, int eventType )
                     case NSHomeFunctionKey  :
                         retval = WXK_HOME;
                         break;
-            //        case NSBeginFunctionKey  :
-            //            retval = WXK_BEGIN;
-            //            break;
+                    case NSBeginFunctionKey  :
+                        retval = WXK_NUMPAD_BEGIN;
+                        break;
                     case NSEndFunctionKey  :
                         retval = WXK_END;
                         break;