Selectable Menu Items
So far, we’ve covered traditional menu items that produce a simple text-oriented label. But that’s not the only type of item users are used to seeing. Swing provides for two selectable menu items: the check box menu item and the radio button menu item.
The JCheckBoxMenuItem Class
Check box menu items are represented by
the JCheckBoxMenuItem
class. As you might have
guessed, this object behaves similarly to the
JCheckBox
object. By clicking on a check box menu
item, you can toggle a UI-defined checkmark that generally appears to
the left of the menu item’s label. There is no mutual exclusion
between adjoining JCheckBoxMenuItem
objects—
the user can check any item without affecting the state of the
others. Figure 14.14 shows the class diagram for the
JCheckBoxMenuItem
component.
Figure 14-14. JCheckBoxMenuItem class diagram
Properties
Table 14.9 shows the properties of the
JCheckBoxMenuItem
class.
JCheckBoxMenuItem
inherits the
JMenuItem
model (ButtonModel
)
and its accessors. The JCheckBoxMenuItem
class
also contains two additional component properties. The
state
property has the value
true
if the menu item is currently in the checked
state and false
if it is not. The
setState()
accessor is synchronized.
The
selectedObjects
property contains an
Object
array of size one, consisting of the text of the menu item if it is currently in the checked state. If it is ...
Get Java Swing now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.