Fixed one_at_a_time and arranger. CURA-3670

1 files changed, 5 insertions, 5 deletions

diff --git a/cura/ConvexHullDecorator.py b/cura/ConvexHullDecorator.py
index da72ffdbe3..404342fb78 100644..100755
--- a/cura/ConvexHullDecorator.py
+++ b/cura/ConvexHullDecorator.py
@@ -59,7 +59,8 @@ class ConvexHullDecorator(SceneNodeDecorator):
         hull = self._compute2DConvexHull()
 
         if self._global_stack and self._node:
-            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and not self._node.getParent().callDecoration("isGroup"):
+            # Parent can be None if node is just loaded.
+            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and (self._node.getParent() is None or not self._node.getParent().callDecoration("isGroup")):
                 hull = hull.getMinkowskiHull(Polygon(numpy.array(self._global_stack.getProperty("machine_head_polygon", "value"), numpy.float32)))
                 hull = self._add2DAdhesionMargin(hull)
         return hull
@@ -79,7 +80,7 @@ class ConvexHullDecorator(SceneNodeDecorator):
             return None
 
         if self._global_stack:
-            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and not self._node.getParent().callDecoration("isGroup"):
+            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and (self._node.getParent() is None or not self._node.getParent().callDecoration("isGroup")):
                 head_with_fans = self._compute2DConvexHeadMin()
                 head_with_fans_with_adhesion_margin = self._add2DAdhesionMargin(head_with_fans)
                 return head_with_fans_with_adhesion_margin
@@ -93,8 +94,7 @@ class ConvexHullDecorator(SceneNodeDecorator):
             return None
 
         if self._global_stack:
-            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and not self._node.getParent().callDecoration("isGroup"):
-
+            if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and (self._node.getParent() is None or not self._node.getParent().callDecoration("isGroup")):
                 # Printing one at a time and it's not an object in a group
                 return self._compute2DConvexHull()
         return None
@@ -335,4 +335,4 @@ class ConvexHullDecorator(SceneNodeDecorator):
     ##  Settings that change the convex hull.
     #
     #   If these settings change, the convex hull should be recalculated.
-    _influencing_settings = {"xy_offset", "mold_enabled", "mold_width"}
\ No newline at end of file
+    _influencing_settings = {"xy_offset", "mold_enabled", "mold_width"}