UI: support cycling callback for non RNA menus

1 files changed, 9 insertions, 0 deletions

diff --git a/source/blender/editors/include/UI_interface.h b/source/blender/editors/include/UI_interface.h
index fc824dc58df..108fcdda613 100644
--- a/source/blender/editors/include/UI_interface.h
+++ b/source/blender/editors/include/UI_interface.h
@@ -361,6 +361,13 @@ typedef void (*uiBlockHandleFunc)(struct bContext *C, void *arg, int event);
 
 typedef void (*uiMenuCreateFunc)(struct bContext *C, struct uiLayout *layout, void *arg1);
 typedef void (*uiMenuHandleFunc)(struct bContext *C, void *arg, int event);
+/**
+ * Used for cycling menu values without opening the menu (Ctrl-Wheel).
+ * \param direction: forward or backwards [1 / -1].
+ * \param arg1: uiBut.poin (as with #uiMenuCreateFunc).
+ * \return true when the button was changed.
+ */
+typedef bool (*uiMenuStepFunc)(struct bContext *C, int direction, void *arg1);
 
 /* Popup Menus
  *
@@ -693,6 +700,8 @@ void    UI_but_func_drawextra_set(
         void (*func)(const struct bContext *C, void *, void *, void *, struct rcti *rect),
         void *arg1, void *arg2);
 
+void    UI_but_func_menu_step_set(uiBut *but, uiMenuStepFunc func);
+
 void    UI_but_func_tooltip_set(uiBut *but, uiButToolTipFunc func, void *argN);
 void    UI_but_tooltip_timer_remove(struct bContext *C, uiBut *but);