org.jdesktop.swingx.plaf
Class PainterUIResource<T extends JComponent>

java.lang.Object
  org.jdesktop.swingx.plaf.PainterUIResource<T>

Type Parameters:

T - a subclass of JComponent

All Implemented Interfaces:

UIResource, Painter<T>

public class PainterUIResource<T extends JComponent>
extends Object
implements Painter<T>, UIResource

An implementation of Painter as a UIResource. UI classes that create Painters should use this class.

Constructor Summary

PainterUIResource(Painter<? super T> p)
Creates a new instance of PainterUIResource with the specified delegate painter.

Method Summary

void	paint(Graphics2D g, T component, int width, int height) Renders to the given Graphics2D object.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PainterUIResource

public PainterUIResource(Painter<? super T> p)

Creates a new instance of PainterUIResource with the specified delegate painter.

Parameters:

p - the delegate painter

Method Detail

paint

public void paint(Graphics2D g,
                  T component,
                  int width,
                  int height)

Renders to the given Graphics2D object. Implementations of this method may modify state on the Graphics2D, and are not required to restore that state upon completion. In most cases, it is recommended that the caller pass in a scratch graphics object. The Graphics2D must never be null.

State on the graphics object may be honored by the paint method, but may not be. For instance, setting the antialiasing rendering hint on the graphics may or may not be respected by the Painter implementation.

The supplied object parameter acts as an optional configuration argument. For example, it could be of type Component. A Painter that expected it could then read state from that Component and use the state for painting. For example, an implementation may read the backgroundColor and use that.

Generally, to enhance reusability, most standard Painters ignore this parameter. They can thus be reused in any context. The object may be null. Implementations must not throw a NullPointerException if the object parameter is null.

Finally, the width and height arguments specify the width and height that the Painter should paint into. More specifically, the specified width and height instruct the painter that it should paint fully within this width and height. Any specified clip on the g param will further constrain the region.

For example, suppose I have a Painter implementation that draws a gradient. The gradient goes from white to black. It "stretches" to fill the painted region. Thus, if I use this Painter to paint a 500 x 500 region, the far left would be black, the far right would be white, and a smooth gradient would be painted between. I could then, without modification, reuse the Painter to paint a region that is 20x20 in size. This region would also be black on the left, white on the right, and a smooth gradient painted between.

Specified by:

paint in interface Painter<T extends JComponent>

Parameters:

g - The Graphics2D to render to. This must not be null.

component - an optional configuration parameter. This may be null.

width - width of the area to paint.

height - height of the area to paint.