UI: Add shortcuts for constraint panels

Only the delete shortcut applies here, although the move up and down
operators can optionally be assigned in the keymap.

See rB1fa40c9f8a81 for more details and rB5d2005cbb54b for the
grease pencil modifier panel implementation, which is the same.
Some refactoring of the constraint delete operator was necessary,
including adding an invoke function.

Differential Revision: https://developer.blender.org/D8238

1 files changed, 24 insertions, 3 deletions

diff --git a/source/blender/editors/interface/interface_templates.c b/source/blender/editors/interface/interface_templates.c
index 3c0b5bd3027..21696b9c1ab 100644
--- a/source/blender/editors/interface/interface_templates.c
+++ b/source/blender/editors/interface/interface_templates.c
@@ -2027,6 +2027,7 @@ void uiTemplateConstraints(uiLayout *UNUSED(layout), bContext *C, bool use_bone_
   ScrArea *sa = CTX_wm_area(C);
   ARegion *region = CTX_wm_region(C);
 
+  Object *ob = ED_object_active_context(C);
   ListBase *constraints = get_constraints(C, use_bone_constraints);
 
   /* Switch between the bone panel ID function and the object panel ID function. */
@@ -2042,11 +2043,15 @@ void uiTemplateConstraints(uiLayout *UNUSED(layout), bContext *C, bool use_bone_
       char panel_idname[MAX_NAME];
       panel_id_func(con, panel_idname);
 
+      /* Create custom data RNA pointer. */
+      PointerRNA *con_ptr = MEM_mallocN(sizeof(PointerRNA), "panel customdata");
+      RNA_pointer_create(&ob->id, &RNA_Constraint, con, con_ptr);
+
       Panel *new_panel = UI_panel_add_instanced(
-          sa, region, &region->panels, panel_idname, i, NULL);
+          sa, region, &region->panels, panel_idname, i, con_ptr);
+
       if (new_panel) {
-        /* Set the list panel functionality function pointers since we don't do it with
-         * python. */
+        /* Set the list panel functionality function pointers since we don't do it with python. */
         new_panel->type->set_list_data_expand_flag = set_constraint_expand_flag;
         new_panel->type->get_list_data_expand_flag = get_constraint_expand_flag;
         new_panel->type->reorder = constraint_reorder;
@@ -2062,6 +2067,22 @@ void uiTemplateConstraints(uiLayout *UNUSED(layout), bContext *C, bool use_bone_
         UI_panel_set_expand_from_list_data(C, panel);
       }
     }
+
+    /* Assuming there's only one group of instanced panels, update the custom data pointers. */
+    Panel *panel = region->panels.first;
+    LISTBASE_FOREACH (bConstraint *, con, constraints) {
+      /* Move to the next instanced panel corresponding to the next constraint. */
+      while ((panel->type == NULL) || !(panel->type->flag & PNL_INSTANCED)) {
+        panel = panel->next;
+        BLI_assert(panel != NULL); /* There shouldn't be fewer panels than constraint panels. */
+      }
+
+      PointerRNA *con_ptr = MEM_mallocN(sizeof(PointerRNA), "constraint panel customdata");
+      RNA_pointer_create(&ob->id, &RNA_Constraint, con, con_ptr);
+      UI_panel_custom_data_set(panel, con_ptr);
+
+      panel = panel->next;
+    }
   }
 }