Like any
IltShelfItem implementation, a card occupies
a slot within a shelf. It is related to the shelf in the same way
as any of the other shelf items described in this section. It is
highly recommended to plan ahead the size of the shelves and the
slot widths, based on the size of the cards and card carriers that
they will host.
When a card is rotated, either manually by a
developer or automatically by the system (following the rotation of
a parent shelf, for instance), all its child card items are rotated
accordingly.
Cards can represent alarms and states
graphically according to their associated state object, in the same
way as network elements can, through alarm balloons and colors
corresponding to the alarm severity. It is possible to define a
customized background image for them.
A card is represented in the form of a
rectangle occupying the whole slot area; it bears a label, as well
as status icons.
You can span a card over the neighboring slot by defining a span
greater than
1
when positioning it into the shelf. The positioning of objects on a
shelf is defined by an object of class
IlpShelfItemPosition and defines the X and Y
slots plus the X and Y spans.
When an object spans over other objects on
the shelf, these objects are removed from the shelf.
It is important to note that the slot index is not related to the
slot numbering. The slot index is used internally by the class
IltShelf to manage slots and cannot be
changed; the slot numbering is defined by the user when creating a
shelf and can be customized.
You should be careful when changing the
orientation of a card, as it affects the positioning of decorations
such as label, status icons, and alarm balloon. The position of the
decorations around a card can be customized through properties.