if (undo_actions == null)
undo_actions = new List<Action> ();
- var existing = current_container.Containers.FirstOrDefault (l => l.Basename == tc.Basename);
- if (existing != null) {
- current_container.RemoveContainer (existing);
- undo_actions.Add (() => current_container.AddTypeContainer (existing));
+ if (current_container.Containers != null)
+ {
+ var existing = current_container.Containers.FirstOrDefault (l => l.Basename == tc.Basename);
+ if (existing != null) {
+ current_container.RemoveContainer (existing);
+ undo_actions.Add (() => current_container.AddTypeContainer (existing));
+ }
}
undo_actions.Add (() => current_container.RemoveContainer (tc));