NLA: actionclip_add now fails on invoke if no NLA track is selected

This makes the NLA_OT_actionclip_add operation (Shift+A while mousing
over the NLA strips area) fail on invocation if no tracks are active.

This stops the annoyance of using the Shift+A menu to select an action
to add, but only getting the error after you select an action.

Differential Revision: https://developer.blender.org/D15737

1 files changed, 32 insertions, 17 deletions

diff --git a/source/blender/editors/space_nla/nla_edit.c b/source/blender/editors/space_nla/nla_edit.c
index 801d032a861..bcdbbb00d1c 100644
--- a/source/blender/editors/space_nla/nla_edit.c
+++ b/source/blender/editors/space_nla/nla_edit.c
@@ -606,6 +606,36 @@ void NLA_OT_view_frame(wmOperatorType *ot)
  * (or the active block if no space in the track).
  * \{ */
 
+/* Get a list of the editable tracks being shown in the NLA. */
+static int nlaedit_get_editable_tracks(bAnimContext *ac, ListBase *anim_data)
+{
+  const int filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ACTIVE | ANIMFILTER_FOREDIT |
+            ANIMFILTER_FCURVESONLY);
+  return ANIM_animdata_filter(ac, anim_data, filter, ac->data, ac->datatype);
+}
+
+static int nlaedit_add_actionclip_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  /* Get editor data. */
+  bAnimContext ac;
+  if (ANIM_animdata_get_context(C, &ac) == 0) {
+    return OPERATOR_CANCELLED;
+  }
+
+  ListBase anim_data = {NULL, NULL};
+  const size_t items = nlaedit_get_editable_tracks(&ac, &anim_data);
+
+  if (items == 0) {
+    BKE_report(op->reports,
+               RPT_ERROR,
+               "No active track(s) to add strip to, select an existing track or add one before "
+               "trying again");
+    return OPERATOR_CANCELLED;
+  }
+
+  return WM_enum_search_invoke(C, op, event);
+}
+
 /* add the specified action as new strip */
 static int nlaedit_add_actionclip_exec(bContext *C, wmOperator *op)
 {
@@ -615,8 +645,6 @@ static int nlaedit_add_actionclip_exec(bContext *C, wmOperator *op)
 
   ListBase anim_data = {NULL, NULL};
   bAnimListElem *ale;
-  size_t items;
-  int filter;
 
   bAction *act;
 
@@ -654,20 +682,7 @@ static int nlaedit_add_actionclip_exec(bContext *C, wmOperator *op)
    */
   nlaedit_add_tracks_empty(&ac);
 
-  /* get a list of the editable tracks being shown in the NLA
-   * - this is limited to active ones for now, but could be expanded to
-   */
-  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ACTIVE | ANIMFILTER_FOREDIT |
-            ANIMFILTER_FCURVESONLY);
-  items = ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
-
-  if (items == 0) {
-    BKE_report(op->reports,
-               RPT_ERROR,
-               "No active track(s) to add strip to, select an existing track or add one before "
-               "trying again");
-    return OPERATOR_CANCELLED;
-  }
+  nlaedit_get_editable_tracks(&ac, &anim_data);
 
   /* for every active track,
    * try to add strip to free space in track or to the top of the stack if no space */
@@ -736,7 +751,7 @@ void NLA_OT_actionclip_add(wmOperatorType *ot)
       "Add an Action-Clip strip (i.e. an NLA Strip referencing an Action) to the active track";
 
   /* api callbacks */
-  ot->invoke = WM_enum_search_invoke;
+  ot->invoke = nlaedit_add_actionclip_invoke;
   ot->exec = nlaedit_add_actionclip_exec;
   ot->poll = nlaop_poll_tweakmode_off;