As implied by its name, the XML view displays an instance in XML format. If you save the XML text, you can load the instance later from the visualizer.
Here is a sample XML file:
<alloy> <sig name="Name" extends="univ"> <atom name="Name$0"/> <atom name="Name$1"/> </sig> <sig name="Date" extends="univ"> <atom name="Date$0"/> </sig> <sig name="BirthdayBook" extends="univ"> <atom name="BirthdayBook$0"/> <atom name="BirthdayBook$1"/> </sig> <field name="known"> <type> <sig name="BirthdayBook"/> <sig name="Name"/> </type> <tuple> <atom name="BirthdayBook$1"/> <atom name="Name$1"/> </tuple> </field> <field name="date"> <type> <sig name="BirthdayBook"/> <sig name="Name"/> <sig name="Date"/> </type> <tuple> <atom name="BirthdayBook$1"/> <atom name="Name$1"/> <atom name="Date$0"/> </tuple> </field> </instance> </alloy>