Introducing Message4. The changes to the related sources are ifdefed with USING_MESSAGE4 which is defined in Message4.h. To use Message4 the Message4.cpp, Message4.h, MessageUtils4.cpp, MessageUtils4.h and MessagePrivate4.h have to be linked to their counterparts without 4 suffix. Then MessageBody.cpp and MessageField.cpp have to be commented out in the app kit Jamfile and r5_message.cpp has to be added. There remain some bugs to be found. Feel free to change that.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14882 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kits/interface/Window.cpp

@@ -34,6 +34,10 @@
 #include <TokenSpace.h>
 #include <MessageUtils.h>
 
+#ifdef USING_MESSAGE4
+#include <MessagePrivate.h>
+#endif
+
 #include <ctype.h>
 #include <stdio.h>
 #include <math.h>
@@ -2249,15 +2253,29 @@ BWindow::task_looper()
 				dispatchNextMessage = false;
 			} else {
 				//	Get the target handler
+#ifdef USING_MESSAGE4
+				//	Use the private BMessage accessor to determine if we are
+				//	using the preferred handler, or if a target has been
+				//	specified
+				BHandler *handler;
+				BMessage::Private messagePrivate(fLastMessage);
+				bool usePreferred = messagePrivate.UsePreferredTarget();
+#else
 				//	Use BMessage friend functions to determine if we are using the
 				//	preferred handler, or if a target has been specified
 				BHandler* handler;
 				bool usePreferred = _use_preferred_target_(fLastMessage);
+#endif
 				if (usePreferred) {
 					handler = PreferredHandler();
 				} else {
+#ifndef USING_MESSAGE4
 					gDefaultTokens.GetToken(_get_message_target_(fLastMessage),
 						B_HANDLER_TOKEN, (void **)&handler);
+#else
+					gDefaultTokens.GetToken(messagePrivate.GetTarget(),
+						B_HANDLER_TOKEN, (void **)&handler);
+#endif
 				}
 
 				// if a target was given, and we should not use the preferred