/*
* $Id: JXPanel.java,v 1.34 2009/05/22 19:43:05 kschaefe Exp $
*
* Copyright 2004 Sun Microsystems, Inc., 4150 Network Circle,
* Santa Clara, California 95054, U.S.A. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.jdesktop.swingx;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Component;
import java.awt.Composite;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.awt.Rectangle;
import javax.swing.JPanel;
import javax.swing.RepaintManager;
import javax.swing.Scrollable;
import javax.swing.plaf.UIResource;
import org.jdesktop.swingx.painter.Painter;
/**
* <p>
* An extended {@code JPanel} that provides additional features. First, the
* component is {@code Scrollable}, using reasonable defaults. Second, the
* component is alpha-channel enabled. This means that the {@code JXPanel} can
* be made fully or partially transparent. Finally, {@code JXPanel} has support
* for {@linkplain Painter painters}.
* </p>
* <p>
* A transparency example, this following code will show the black background of
* the parent:
*
* <pre>
* JXPanel panel = new JXPanel();
* panel.add(new JButton("Push Me"));
* panel.setAlpha(.5f);
*
* container.setBackground(Color.BLACK);
* container.add(panel);
* </pre>
*
* </p>
* <p>
* A painter example, this following code will show how to add a simple painter:
*
* <pre>
* JXPanel panel = new JXPanel();
* panel.setBackgroundPainter(new PinstripePainter());
* </pre>
*
* </p>
*
* @author rbair
* @see Scrollable
* @see Painter
*/
public class JXPanel extends JPanel implements Scrollable {
private boolean scrollableTracksViewportHeight = true;
private boolean scrollableTracksViewportWidth = true;
/**
* The alpha level for this component.
*/
private float alpha = 1.0f;
/**
* If the old alpha value was 1.0, I keep track of the opaque setting because
* a translucent component is not opaque, but I want to be able to restore
* opacity to its default setting if the alpha is 1.0. Honestly, I don't know
* if this is necessary or not, but it sounded good on paper :)
* <p>TODO: Check whether this variable is necessary or not</p>
*/
private boolean oldOpaque;
/**
* Indicates whether this component should inherit its parent alpha value
*/
private boolean inheritAlpha = true;
/**
* Specifies the Painter to use for painting the background of this panel.
* If no painter is specified, the normal painting routine for JPanel
* is called. Old behavior is also honored for the time being if no
* backgroundPainter is specified
*/
private Painter backgroundPainter;
/**
* Creates a new <code>JXPanel</code> with a double buffer
* and a flow layout.
*/
public JXPanel() {
}
/**
* Creates a new <code>JXPanel</code> with <code>FlowLayout</code>
* and the specified buffering strategy.
* If <code>isDoubleBuffered</code> is true, the <code>JXPanel</code>
* will use a double buffer.
*
* @param isDoubleBuffered a boolean, true for double-buffering, which
* uses additional memory space to achieve fast, flicker-free
* updates
*/
public JXPanel(boolean isDoubleBuffered) {
super(isDoubleBuffered);
}
/**
* Create a new buffered JXPanel with the specified layout manager
*
* @param layout the LayoutManager to use
*/
public JXPanel(LayoutManager layout) {
super(layout);
}
/**
* Creates a new JXPanel with the specified layout manager and buffering
* strategy.
*
* @param layout the LayoutManager to use
* @param isDoubleBuffered a boolean, true for double-buffering, which
* uses additional memory space to achieve fast, flicker-free
* updates
*/
public JXPanel(LayoutManager layout, boolean isDoubleBuffered) {
super(layout, isDoubleBuffered);
}
/**
* Set the alpha transparency level for this component. This automatically
* causes a repaint of the component.
*
* <p>TODO add support for animated changes in translucency</p>
*
* @param alpha must be a value between 0 and 1 inclusive.
*/
public void setAlpha(float alpha) {
if (this.alpha != alpha) {
assert alpha >= 0 && alpha <= 1.0;
float oldAlpha = this.alpha;
this.alpha = alpha;
if (alpha > 0f && alpha < 1f) {
if (oldAlpha == 1) {
//it used to be 1, but now is not. Save the oldOpaque
oldOpaque = isOpaque();
setOpaque(false);
}
RepaintManager manager = RepaintManager.currentManager(this);
RepaintManager trm = SwingXUtilities.getTranslucentRepaintManager(manager);
RepaintManager.setCurrentManager(trm);
} else if (alpha == 1) {
//restore the oldOpaque if it was true (since opaque is false now)
if (oldOpaque) {
setOpaque(true);
}
}
firePropertyChange("alpha", oldAlpha, alpha);
repaint();
}
}
/**
* @return the alpha translucency level for this component. This will be
* a value between 0 and 1, inclusive.
*/
public float getAlpha() {
return alpha;
}
/**
* Unlike other properties, alpha can be set on a component, or on one of
* its parents. If the alpha of a parent component is .4, and the alpha on
* this component is .5, effectively the alpha for this component is .4
* because the lowest alpha in the heirarchy "wins"
*/
public float getEffectiveAlpha() {
if (inheritAlpha) {
float a = alpha;
Component c = this;
while ((c = c.getParent()) != null) {
if (c instanceof JXPanel) {
a = Math.min(((JXPanel)c).getAlpha(), a);
}
}
return a;
} else {
return alpha;
}
}
/**
* Returns the state of the panel with respect to inheriting alpha values.
*
* @return {@code true} if this panel inherits alpha values; {@code false}
* otherwise
* @see JXPanel#setInheritAlpha(boolean)
*/
public boolean isInheritAlpha() {
return inheritAlpha;
}
/**
* Determines if the effective alpha of this component should include the
* alpha of ancestors.
*
* @param val
* {@code true} to include ancestral alpha data; {@code false}
* otherwise
* @see #isInheritAlpha()
* @see #getEffectiveAlpha()
*/
public void setInheritAlpha(boolean val) {
if (inheritAlpha != val) {
inheritAlpha = val;
firePropertyChange("inheritAlpha", !inheritAlpha, inheritAlpha);
}
}
/**
* {@inheritDoc}
*/
public boolean getScrollableTracksViewportHeight() {
return scrollableTracksViewportHeight;
}
/**
* {@inheritDoc}
*/
public boolean getScrollableTracksViewportWidth() {
return scrollableTracksViewportWidth;
}
/**
* {@inheritDoc}
*/
public Dimension getPreferredScrollableViewportSize() {
return getPreferredSize();
}
/**
* {@inheritDoc}
*/
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction) {
return 10;
}
/**
* {@inheritDoc}
*/
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction) {
return 10;
}
/**
* @param scrollableTracksViewportHeight The scrollableTracksViewportHeight to set.
*/
public void setScrollableTracksViewportHeight(boolean scrollableTracksViewportHeight) {
this.scrollableTracksViewportHeight = scrollableTracksViewportHeight;
}
/**
* @param scrollableTracksViewportWidth The scrollableTracksViewportWidth to set.
*/
public void setScrollableTracksViewportWidth(boolean scrollableTracksViewportWidth) {
this.scrollableTracksViewportWidth = scrollableTracksViewportWidth;
}
/**
* Sets the background color for this component by
*
* @param bg
* the desired background <code>Color</code>
* @see java.swing.JComponent#getBackground
* @see #setOpaque
*
* @beaninfo
* preferred: true
* bound: true
* attribute: visualUpdate true
* description: The background color of the component.
*/
@Override
public void setBackground(Color bg) {
super.setBackground(bg);
//TODO problem with SwingX #964. Had to undo changes.
//Change causes background to be painter when using setOpaque=false hack
// if (canInstallBackgroundUIResourceAsPainter(bg)) {
// setBackgroundPainter(new PainterUIResource(new MattePainter<JXPanel>(bg)));
// } else {
// setBackgroundPainter(new MattePainter<JXPanel>(bg));
// }
}
private boolean canInstallBackgroundUIResourceAsPainter(Color bg) {
Painter<?> p = getBackgroundPainter();
return bg instanceof UIResource && (p == null || p instanceof UIResource);
}
/**
* Sets a Painter to use to paint the background of this JXPanel.
*
* @param p the new painter
* @see #getBackgroundPainter()
*/
public void setBackgroundPainter(Painter p) {
Painter old = getBackgroundPainter();
backgroundPainter = p;
firePropertyChange("backgroundPainter", old, getBackgroundPainter());
repaint();
}
/**
* Returns the current background painter. The default value of this property
* is a painter which draws the normal JPanel background according to the current look and feel.
* @return the current painter
* @see #setBackgroundPainter(Painter)
* @see #isPaintBorderInsets()
*/
public Painter getBackgroundPainter() {
return backgroundPainter;
}
private boolean paintBorderInsets = true;
/**
* Returns true if the background painter should paint where the border is
* or false if it should only paint inside the border. This property is
* true by default. This property affects the width, height,
* and intial transform passed to the background painter.
*/
public boolean isPaintBorderInsets() {
return paintBorderInsets;
}
/**
* Sets the paintBorderInsets property.
* Set to true if the background painter should paint where the border is
* or false if it should only paint inside the border. This property is true by default.
* This property affects the width, height,
* and intial transform passed to the background painter.
*
* This is a bound property.
*/
public void setPaintBorderInsets(boolean paintBorderInsets) {
boolean old = this.isPaintBorderInsets();
this.paintBorderInsets = paintBorderInsets;
firePropertyChange("paintBorderInsets", old, isPaintBorderInsets());
}
/**
* Overriden paint method to take into account the alpha setting
* @param g
*/
@Override
public void paint(Graphics g) {
Graphics2D g2d = (Graphics2D)g;
Composite oldComp = g2d.getComposite();
float alpha = getEffectiveAlpha();
Composite alphaComp = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha);
g2d.setComposite(alphaComp);
super.paint(g2d);
g2d.setComposite(oldComp);
}
/**
* Overridden to provide Painter support. It will call backgroundPainter.paint()
* if it is not null, else it will call super.paintComponent().
*/
@Override
protected void paintComponent(Graphics g) {
if(backgroundPainter != null) {
if (isOpaque()) super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g.create();
try {
// account for the insets
if(isPaintBorderInsets()) {
backgroundPainter.paint(g2, this, this.getWidth(), this.getHeight());
} else {
Insets ins = this.getInsets();
g2.translate(ins.left, ins.top);
backgroundPainter.paint(g2, this,
this.getWidth() - ins.left - ins.right,
this.getHeight() - ins.top - ins.bottom);
}
} finally {
g2.dispose();
}
} else {
super.paintComponent(g);
}
}
}