If you select different items in the list, only the last item you select remains highlighted. The way in which the items in a list panel interact upon selection can be controlled with the :interaction keyword.
The list produced in the example above is known as a single-selection list because only one item at a time may be selected. List panels are :single-selection by default.
There are also multiple-selection and extended-selection lists available. The possible interactions for list panels are:
:single-selection -- only one item may be selected :multiple-selection -- more than one item may be selected :extended-selection -- see Extended selection To get a particular interaction, supply one of the values above to the :interaction keyword, like this:
(contain
(make-instance
'list-panel
:items '("Red" "Green" "Blue"):interaction :multiple-selection))
Note that :no-selection is not a supported choice for list panels. To display a list of items with no selection possible you should use a display pane.