bim.add_drawing_to_sheet - poll message

src/bonsai/bonsai/bim/module/drawing/operator.py

@@ -1481,11 +1481,19 @@ class AddDrawingToSheet(bpy.types.Operator, tool.Ifc.Operator):
     @classmethod
     def poll(cls, context):
         props = context.scene.DocProperties
-        return props.drawings and props.sheets and context.scene.BIMProperties.data_dir
+        # Won't be visible in UI anyway.
+        if not props.sheets or not context.scene.BIMProperties.data_dir:
+            return False
+        if not tool.Drawing.get_active_drawing_item():
+            cls.poll_message_set("No drawing selected.")
+            return False
+        return True
 
     def _execute(self, context):
         props = context.scene.DocProperties
-        active_drawing = props.drawings[props.active_drawing_index]
+        active_drawing = tool.Drawing.get_active_drawing_item()
+        assert active_drawing
+
         active_sheet = tool.Drawing.get_active_sheet(context)
         drawing = tool.Ifc.get().by_id(active_drawing.ifc_definition_id)
         drawing_reference = tool.Drawing.get_drawing_document(drawing)

src/bonsai/bonsai/tool/drawing.py

@@ -847,6 +847,15 @@ class Drawing(bonsai.core.tool.Drawing):
         props = context.scene.DocProperties
         return next(s for s in props.sheets[: props.active_sheet_index + 1][::-1] if s.is_sheet)
 
+    @classmethod
+    def get_active_drawing_item(cls) -> Union[bpy.types.PropertyGroup, None]:
+        props = bpy.context.scene.DocProperties
+        drawing_index = props.active_drawing_index
+        if len(props.drawings) > drawing_index >= 0:
+            item = props.drawings[drawing_index]
+            if item.is_drawing:
+                return item
+
     @classmethod
     def import_text_attributes(cls, obj: bpy.types.Object) -> None:
         from bonsai.bim.module.drawing.prop import BOX_ALIGNMENT_POSITIONS