Java Reference
In-Depth Information
Figure 4-15 shows the test driver program results.
Figure 4-15.
The new OvalPanel component
■
Note
By default,
JPanel
components are opaque. This differs from
JComponent
, whose
opacity
property setting by default is
false
. A
false
setting for
opacity
means the component is transparent.
Customizing a JPanel Look and Feel
The available set of
UIResource
-related properties for a
JPanel
is shown in Table 4-16. For the
JPanel
component, there are five different properties. These settings may have an effect on the
components within the panel.
Table 4-16.
JPanel UIResource Elements
Property String
Object Type
Panel.background
Color
Panel.border
Border
Panel.font
Font
Panel.foreground
Color
PanelUI
String
Summary
In this chapter, you explored the root of all Swing components: the
JComponent
class. From
there, you looked at some of the common elements of all components, such as tooltips, as well
as specific components such as
JLabel
. You also learned how to put glyphs (nonverbal images)
on components with the help of the
Icon
interface and the
ImageIcon
class, and the
GrayFilter
image filter for disabled icons.
