... PEARpackage. In the ppaacckkaaggee xxmmllfile, they are identified byfour pieces of information: their handle, their name,their email address, and their role in the package. As aresult, the aaddddMMaaiinnttaaiinneerr(())method ... To make sure that only the list values areused, therefore, we need to prevent the user from edit-ing the text in the entry area. This is done the same wayas we did for the warnings area, with ... bar thatlets the user save their package file and exit the appli-cation. The menu bar needs a menu for file operationsand a menu for help and about information. The menubar is the only widget...