gui/controls/treeview.py
def set_has_children(self, has_children=True):
        "Force appearance of the button next to the item"
        # This is useful to allow the user to expand the items which don't have
        # any children now, but instead adding them only when needed, thus 
        # minimizing memory usage and loading time.
        self._tree_model._tree_view.wx_obj.SetItemHasChildren(self.wx_item, 
                                                              has_children)
def set_has_children(self, has_children=True):
        "Force appearance of the button next to the item"
        # This is useful to allow the user to expand the items which don't have
        # any children now, but instead adding them only when needed, thus 
        # minimizing memory usage and loading time.
        self._tree_model._tree_view.wx_obj.SetItemHasChildren(self.wx_item, 
                                                              has_children)
Force appearance of the button next to the item