prevent data item from re-initializing if user clicks change_dir_button, but then cancels
prevent data item from re-initializing if user clicks change_dir_button, but then cancels

lfairchild/PmagPy,Caoimhinmg/PmagPy,lfairchild/PmagPy,lfairchild/PmagPy,Caoimhinmg/PmagPy,Caoimhinmg/PmagPy