I'm trying to capture a right mouse click on a PtList. I can set the Pt_ALL_BUTTONS flag which allows me to select lines
 with the right mouse button but I need to know if it is the right or left button. So, instead I tried to use the raw 
event and set Ph_EV_BUT_PRESS. But the event doesn't fire. It works for PtPane, PtButton, etc...just not for PtList.
   Is there some other flag that needs to be set to allow PtList to capture the raw mouse button press event?