Keyframes on NLA-Strip F-Curves are detected by RNA buttons too

source/blender/blenkernel/BKE_fcurve.h

@@ -223,12 +223,12 @@ struct FCurve *id_data_find_fcurve(ID *id, void *data, struct StructRNA *type, c
  */
 int list_find_data_fcurves(ListBase *dst, ListBase *src, const char *dataPrefix, const char *dataName);
 
-/* find an f-curve based on an rna property. */
+/* Find an f-curve based on an rna property. */
 struct FCurve *rna_get_fcurve(struct PointerRNA *ptr, struct PropertyRNA *prop, int rnaindex,
-                              struct AnimData **adt, struct bAction **action, bool *r_driven);
+                              struct AnimData **adt, struct bAction **action, bool *r_driven, bool *r_special);
 /* Same as above, but takes a context data, temp hack needed for complex paths like texture ones. */
 struct FCurve *rna_get_fcurve_context_ui(struct bContext *C, struct PointerRNA *ptr, struct PropertyRNA *prop,
-                                         int rnaindex, struct AnimData **adt, struct bAction **action, bool *r_driven);
+                                         int rnaindex, struct AnimData **adt, struct bAction **action, bool *r_driven, bool *r_special);
 
 /* Binary search algorithm for finding where to 'insert' BezTriple with given frame number.
  * Returns the index to insert at (data already at that index will be offset if replace is 0)

source/blender/blenkernel/intern/fcurve.c

@@ -309,19 +309,22 @@ int list_find_data_fcurves(ListBase *dst, ListBase *src, const char *dataPrefix,
 	return matches;
 }
 
-FCurve *rna_get_fcurve(PointerRNA *ptr, PropertyRNA *prop, int rnaindex, AnimData **adt, bAction **action, bool *r_driven)
+FCurve *rna_get_fcurve(PointerRNA *ptr, PropertyRNA *prop, int rnaindex, AnimData **adt, 
+                       bAction **action, bool *r_driven, bool *r_special)
 {
-	return rna_get_fcurve_context_ui(NULL, ptr, prop, rnaindex, adt, action, r_driven);
+	return rna_get_fcurve_context_ui(NULL, ptr, prop, rnaindex, adt, action, r_driven, r_special);
 }
 
-FCurve *rna_get_fcurve_context_ui(bContext *C, PointerRNA *ptr, PropertyRNA *prop, int rnaindex,
-                                  AnimData **animdata, bAction **action, bool *r_driven)
+FCurve *rna_get_fcurve_context_ui(bContext *C, PointerRNA *ptr, PropertyRNA *prop, int rnaindex, AnimData **animdata,
+                                  bAction **action, bool *r_driven, bool *r_special)
 {
 	FCurve *fcu = NULL;
 	PointerRNA tptr = *ptr;
 	
 	if (animdata) *animdata = NULL;
 	*r_driven = false;
+	*r_special = false;
+	
 	if (action) *action = NULL;
 	
 	/* there must be some RNA-pointer + property combon */
@@ -343,6 +346,7 @@ FCurve *rna_get_fcurve_context_ui(bContext *C, PointerRNA *ptr, PropertyRNA *pro
 					path = RNA_path_from_ID_to_property(&tptr, prop);
 				}
 				
+				// XXX: the logic here is duplicated with a function up above
 				if (path) {
 					/* animation takes priority over drivers */
 					if (adt->action && adt->action->curves.first) {
@@ -380,6 +384,32 @@ FCurve *rna_get_fcurve_context_ui(bContext *C, PointerRNA *ptr, PropertyRNA *pro
 					}
 				}
 			}
+			
+			/* if we still haven't found anything, check whether it's a "special" property */
+			if ((fcu == NULL) && (adt->nla_tracks.first)) {
+				NlaTrack *nlt;
+				const char *propname = RNA_property_identifier(prop);
+				
+				for (nlt = adt->nla_tracks.first; nlt; nlt = nlt->next) {
+					NlaStrip *strip;
+					
+					if (fcu)
+						break;
+					
+					/* FIXME: need to do recursive search here for correctness, 
+					 * but this will do for most use cases (i.e. interactive editing),
+					 * where nested strips can't be easily edited
+					 */
+					for (strip = nlt->strips.first; strip; strip = strip->next) {
+						fcu = list_find_fcurve(&strip->fcurves, propname, rnaindex);
+						
+						if (fcu) {
+							*r_special = true;
+							break;
+						}
+					}
+				}
+			}
 		}
 		MEM_SAFE_FREE(path);
 	}

source/blender/editors/interface/interface_anim.c

@@ -54,13 +54,13 @@
 
 #include "interface_intern.h"
 
-static FCurve *ui_but_get_fcurve(uiBut *but, AnimData **adt, bAction **action, bool *r_driven)
+static FCurve *ui_but_get_fcurve(uiBut *but, AnimData **adt, bAction **action, bool *r_driven, bool *r_special)
 {
 	/* for entire array buttons we check the first component, it's not perfect
 	 * but works well enough in typical cases */
 	int rnaindex = (but->rnaindex == -1) ? 0 : but->rnaindex;
 
-	return rna_get_fcurve_context_ui(but->block->evil_C, &but->rnapoin, but->rnaprop, rnaindex, adt, action, r_driven);
+	return rna_get_fcurve_context_ui(but->block->evil_C, &but->rnapoin, but->rnaprop, rnaindex, adt, action, r_driven, r_special);
 }
 
 void ui_but_anim_flag(uiBut *but, float cfra)
@@ -69,11 +69,16 @@ void ui_but_anim_flag(uiBut *but, float cfra)
 	bAction *act;
 	FCurve *fcu;
 	bool driven;
-
+	bool special;
+	
 	but->flag &= ~(UI_BUT_ANIMATED | UI_BUT_ANIMATED_KEY | UI_BUT_DRIVEN);
-
-	fcu = ui_but_get_fcurve(but, &adt, &act, &driven);
-
+	
+	/* NOTE: "special" is reserved for special F-Curves stored on the animation data
+	 *        itself (which are used to animate properties of the animation data).
+	 *        We count those as "animated" too for now
+	 */
+	fcu = ui_but_get_fcurve(but, &adt, &act, &driven, &special);
+	
 	if (fcu) {
 		if (!driven) {
 			but->flag |= UI_BUT_ANIMATED;
@@ -98,10 +103,10 @@ bool ui_but_anim_expression_get(uiBut *but, char *str, size_t maxlen)
 {
 	FCurve *fcu;
 	ChannelDriver *driver;
-	bool driven;
-
-	fcu = ui_but_get_fcurve(but, NULL, NULL, &driven);
-
+	bool driven, special;
+	
+	fcu = ui_but_get_fcurve(but, NULL, NULL, &driven, &special);
+	
 	if (fcu && driven) {
 		driver = fcu->driver;
 
@@ -118,9 +123,9 @@ bool ui_but_anim_expression_set(uiBut *but, const char *str)
 {
 	FCurve *fcu;
 	ChannelDriver *driver;
-	bool driven;
+	bool driven, special;
 
-	fcu = ui_but_get_fcurve(but, NULL, NULL, &driven);
+	fcu = ui_but_get_fcurve(but, NULL, NULL, &driven, &special);
 
 	if (fcu && driven) {
 		driver = fcu->driver;
@@ -215,8 +220,9 @@ void ui_but_anim_autokey(bContext *C, uiBut *but, Scene *scene, float cfra)
 	bAction *action;
 	FCurve *fcu;
 	bool driven;
+	bool special;
 
-	fcu = ui_but_get_fcurve(but, NULL, &action, &driven);
+	fcu = ui_but_get_fcurve(but, NULL, &action, &driven, &special);
 
 	if (fcu && !driven) {
 		id = but->rnapoin.id.data;

source/blender/makesrna/intern/rna_access.c

@@ -1622,7 +1622,7 @@ bool RNA_property_animateable(PointerRNA *ptr, PropertyRNA *prop)
 bool RNA_property_animated(PointerRNA *ptr, PropertyRNA *prop)
 {
 	int len = 1, index;
-	bool driven;
+	bool driven, special;
 
 	if (!prop)
 		return false;
@@ -1631,7 +1631,7 @@ bool RNA_property_animated(PointerRNA *ptr, PropertyRNA *prop)
 		len = RNA_property_array_length(ptr, prop);
 
 	for (index = 0; index < len; index++) {
-		if (rna_get_fcurve(ptr, prop, index, NULL, NULL, &driven))
+		if (rna_get_fcurve(ptr, prop, index, NULL, NULL, &driven, &special))
 			return true;
 	}