Annoyance fix:

Using scrollwheel on properties window halted when it was over
a list-button. Now it disables handling wheel events when you use
scrollwheel outside of lists first.

Implementation note: UI event handlers have priority over other
keymaps. That's OK. In this case it's simple conflict, for which
no design solution exists... wouldn't know how to do this nicer!
Code is nice local and can be improved when we look into other
conflicts...

1 files changed, 24 insertions, 8 deletions

diff --git a/source/blender/windowmanager/intern/wm_event_system.c b/source/blender/windowmanager/intern/wm_event_system.c
index 03ad58e67d5..0a1f3035a84 100644
--- a/source/blender/windowmanager/intern/wm_event_system.c
+++ b/source/blender/windowmanager/intern/wm_event_system.c
@@ -302,6 +302,12 @@ void wm_event_do_notifiers(bContext *C)
 	CTX_wm_window_set(C, NULL);
 }
 
+static int wm_event_always_pass(wmEvent *event)
+{
+	/* some events we always pass on, to ensure proper communication */
+	return ISTIMER(event->type) || (event->type == WINDEACTIVATE);
+}
+
 /* ********************* ui handler ******************* */
 
 static int wm_handler_ui_call(bContext *C, wmEventHandler *handler, wmEvent *event, int always_pass)
@@ -309,8 +315,19 @@ static int wm_handler_ui_call(bContext *C, wmEventHandler *handler, wmEvent *eve
 	ScrArea *area= CTX_wm_area(C);
 	ARegion *region= CTX_wm_region(C);
 	ARegion *menu= CTX_wm_menu(C);
+	static int do_wheel_ui= 1;
+	int is_wheel= ELEM(event->type, WHEELUPMOUSE, WHEELDOWNMOUSE);
 	int retval;
-			
+	
+	/* UI is quite agressive with swallowing events, like scrollwheel */
+	/* I realize this is not extremely nice code... when UI gets keymaps it can be maybe smarter */
+	if(do_wheel_ui==0) {
+		if(is_wheel)
+			return WM_HANDLER_CONTINUE;
+		else if(wm_event_always_pass(event)==0)
+			do_wheel_ui= 1;
+	}
+	
 	/* we set context to where ui handler came from */
 	if(handler->ui_area) CTX_wm_area_set(C, handler->ui_area);
 	if(handler->ui_region) CTX_wm_region_set(C, handler->ui_region);
@@ -330,10 +347,14 @@ static int wm_handler_ui_call(bContext *C, wmEventHandler *handler, wmEvent *eve
 		CTX_wm_region_set(C, NULL);
 		CTX_wm_menu_set(C, NULL);
 	}
-
+	
 	if(retval == WM_UI_HANDLER_BREAK)
 		return WM_HANDLER_BREAK;
-
+	
+	/* event not handled in UI, if wheel then we temporarily disable it */
+	if(is_wheel)
+		do_wheel_ui= 0;
+	
 	return WM_HANDLER_CONTINUE;
 }
 
@@ -1100,11 +1121,6 @@ static int wm_eventmatch(wmEvent *winevent, wmKeyMapItem *kmi)
 	return 1;
 }
 
-static int wm_event_always_pass(wmEvent *event)
-{
-	/* some events we always pass on, to ensure proper communication */
-	return ISTIMER(event->type) || (event->type == WINDEACTIVATE);
-}
 
 /* operator exists */
 static void wm_event_modalkeymap(const bContext *C, wmOperator *op, wmEvent *event)