Person objects not only have a FirstName
and a Surname property, but also an address
property pointing to another domain object –
an instance of class Location.
The EditPersonForm gives the user a GUI to
edit particular Person objects. In this case,
we are looking at Arnold Schwarzenegger, probably
the only Austrian Person most people in the world know
and who is not dead (like Mozart or Freud):
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Labeled with "1" is Arnold's address (or a compact
representation thereof); labeled with "2" is the
menu item "Pick location". Clicking on "Pick location"
will open the Pick location form, essentially a
search dialog. It enables the user to search for a
particular location and assign it to the Arnold object
as new address:
In this illustration, we filter all addresses in the
database by country (1), click Search (2)
and get a list to pick a Location from (3).
As soon as we click on a Location object in the
list, we return to the EditPersonForm and see
that the Location has indeed been assigned to
Arnold's Location property:
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So far so good. If you have read the page FIXME, you will
recognize this mechanism as re-call at work: the EditPersonForm
with Arnold "calls" the PickLocation form, which
returns to Arnold, the caller, when the user is done.
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