This service specifies a list box model which is data-aware and thus can be bound to a
database field, and additionally supports binding to arbitrary external values.
There are four possible ways how a BindableDatabaseListBox exchanges
values with an external binding, the following lists explains all of them. If a new binding
is set at a BindableDatabaseListBox, the types from the following list are
tried in descending order: The first type supported by the binding is used for data exchange.
sequences of integers: When used, the integers in the sequence will represent
the indexes of the selected entries of the list box.
integer values: When used, the value will represent the index of the selected entry.
If no entry is selected, -1 will be transfered. If more than one entry is selected, NULL
will be transfered.
sequences of strings: When used, the strings in the sequence present the texts
of the selected entries of the list box.
string values: When used. the value will represent the text of the selected entry.
If no entry is selected, an empty string will be transfered. If more than one entry is selected,
NULL will be transfered.
