Fix sheets related poll errors

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

@@ -1549,8 +1549,7 @@ class OpenSheet(bpy.types.Operator, tool.Ifc.Operator):
     @classmethod
     def poll(cls, context):
         props = context.scene.DocProperties
-        active_sheet = props.sheets[props.active_sheet_index]
-        if not active_sheet.is_sheet:
+        if not tool.Drawing.get_active_sheet_item(is_sheet=True):
             cls.poll_message_set("No sheet selected.")
             return False
         return True
@@ -1681,9 +1680,11 @@ class RemoveDrawingFromSheet(bpy.types.Operator, tool.Ifc.Operator):
     @classmethod
     def poll(cls, context):
         props = context.scene.DocProperties
-        active_sheet = props.sheets[props.active_sheet_index]
+        active_item = tool.Drawing.get_active_sheet_item()
+        if active_item is None:
+            return False
 
-        if active_sheet.reference_type == "TITLEBLOCK":
+        if active_item.reference_type == "TITLEBLOCK":
             cls.poll_message_set("No effect deleting this.")
             return False
         return True
@@ -1721,8 +1722,7 @@ class CreateSheets(bpy.types.Operator, tool.Ifc.Operator):
     @classmethod
     def poll(cls, context):
         props = context.scene.DocProperties
-        active_sheet = props.sheets[props.active_sheet_index]
-        if not active_sheet.is_sheet:
+        if not tool.Drawing.get_active_sheet_item(is_sheet=True):
             cls.poll_message_set("No sheet selected.")
             return False
         return props.sheets and context.scene.BIMProperties.data_dir
@@ -2057,9 +2057,7 @@ class ActivateDrawingFromSheet(bpy.types.Operator, ActivateDrawingBase):
     @classmethod
     def poll(cls, context):
         props = context.scene.DocProperties
-        active_sheet = props.sheets[props.active_sheet_index]
-        is_drawing_selected = active_sheet.reference_type == "DRAWING"
-        if not is_drawing_selected:
+        if not tool.Drawing.get_active_sheet_item(reference_type="DRAWING"):
             cls.poll_message_set("No drawing selected.")
             return False
         return True

src/bonsai/bonsai/tool/drawing.py

@@ -889,6 +889,23 @@ class Drawing(bonsai.core.tool.Drawing):
             if item.is_drawing:
                 return item
 
+    @classmethod
+    def get_active_sheet_item(
+        cls, *, is_sheet: bool = False, reference_type: str = ""
+    ) -> Union[bpy.types.PropertyGroup, None]:
+        props = bpy.context.scene.DocProperties
+        sheet_index = props.active_sheet_index
+        if len(props.sheets) > sheet_index >= 0:
+            item = props.sheets[sheet_index]
+            if not is_sheet and not reference_type:
+                return item
+            if is_sheet:
+                if item.is_sheet:
+                    return item
+            elif reference_type:
+                if item.reference_type == reference_type:
+                    return item
+
     @classmethod
     def import_text_attributes(cls, obj: bpy.types.Object) -> None:
         from bonsai.bim.module.drawing.prop import BOX_ALIGNMENT_POSITIONS