Java Reference
In-Depth Information
If you need
paintComponent
to execute (i.e., if you want to update the graphics drawn
on a Swing component), you can call method
repaint
, which returns
void
, takes no argu-
ments and is inherited by all
JComponent
s indirectly from class
Component
(package
java.awt
).
Class
Color
declares methods and constants for manipulating colors in a Java program.
The predeclared color constants are summarized in Fig. 13.3, and several color methods
and constructors are summarized in Fig. 13.4. Two of the methods in Fig. 13.4 are
Graph-
ics
methods that are specific to colors.
Color constant
RGB value
public static final
Color
RED
255, 0, 0
public static final
Color
GREEN
0, 255, 0
public static final
Color
BLUE
0, 0, 255
public static final
Color
ORANGE
255, 200, 0
public static final
Color
PINK
255, 175, 175
public static final
Color
CYAN
0, 255, 255
public static final
Color
MAGENTA
255, 0, 255
public static final
Color
YELLOW
255, 255, 0
public static final
Color
BLACK
0, 0, 0
public static final
Color
WHITE
255, 255, 255
public static final
Color
GRAY
128, 128, 128
public static final
Color
LIGHT_GRAY
192, 192, 192
public static final
Color
DARK_GRAY
64, 64, 64
Fig. 13.3
|
Color
constants and their RGB values.
Method
Description
Color
constructors and methods
public
Color(
int
r,
int
g,
int
b)
Creates a color based on red, green and blue components expressed as integers
from 0 to 255.
public
Color(
float
r,
float
g,
float
b)
Creates a color based on red, green and blue components expressed as floating-
point values from 0.0 to 1.0.
public int
getRed()
Returns a value between 0 and 255 representing the red content.
Fig. 13.4
|
Color
methods and color-related
Graphics
methods. (Part 1 of 2.)
