A layout manager that displays a single component in the center of its container.
/*
* JCommon : a free general purpose class library for the Java(tm) platform
*
*
* (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* 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 Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* -----------------
* CenterLayout.java
* -----------------
* (C) Copyright 2000-2005, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* $Id: CenterLayout.java,v 1.6 2005/11/16 15:58:40 taqua Exp $
*
* Changes (from 5-Nov-2001)
* -------------------------
* 05-Nov-2001 : Changed package to com.jrefinery.layout.* (DG);
* 10-Oct-2002 : Fixed errors reported by Checkstyle (DG);
*
*/
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.io.Serializable;
/**
* A layout manager that displays a single component in the center of its
* container.
*
* @author David Gilbert
*/
public class CenterLayout implements LayoutManager, Serializable {
/** For serialization. */
private static final long serialVersionUID = 469319532333015042L;
/**
* Creates a new layout manager.
*/
public CenterLayout() {
}
/**
* Returns the preferred size.
*
* @param parent
* the parent.
*
* @return the preferred size.
*/
public Dimension preferredLayoutSize(final Container parent) {
synchronized (parent.getTreeLock()) {
final Insets insets = parent.getInsets();
if (parent.getComponentCount() > 0) {
final Component component = parent.getComponent(0);
final Dimension d = component.getPreferredSize();
return new Dimension((int) d.getWidth() + insets.left + insets.right, (int) d.getHeight()
+ insets.top + insets.bottom);
} else {
return new Dimension(insets.left + insets.right, insets.top + insets.bottom);
}
}
}
/**
* Returns the minimum size.
*
* @param parent
* the parent.
*
* @return the minimum size.
*/
public Dimension minimumLayoutSize(final Container parent) {
synchronized (parent.getTreeLock()) {
final Insets insets = parent.getInsets();
if (parent.getComponentCount() > 0) {
final Component component = parent.getComponent(0);
final Dimension d = component.getMinimumSize();
return new Dimension(d.width + insets.left + insets.right, d.height + insets.top
+ insets.bottom);
} else {
return new Dimension(insets.left + insets.right, insets.top + insets.bottom);
}
}
}
/**
* Lays out the components.
*
* @param parent
* the parent.
*/
public void layoutContainer(final Container parent) {
synchronized (parent.getTreeLock()) {
if (parent.getComponentCount() > 0) {
final Insets insets = parent.getInsets();
final Dimension parentSize = parent.getSize();
final Component component = parent.getComponent(0);
final Dimension componentSize = component.getPreferredSize();
final int xx = insets.left
+ (Math.max((parentSize.width - insets.left - insets.right - componentSize.width) / 2,
0));
final int yy = insets.top
+ (Math.max(
(parentSize.height - insets.top - insets.bottom - componentSize.height) / 2, 0));
component.setBounds(xx, yy, componentSize.width, componentSize.height);
}
}
}
/**
* Not used.
*
* @param comp
* the component.
*/
public void addLayoutComponent(final Component comp) {
// not used.
}
/**
* Not used.
*
* @param comp
* the component.
*/
public void removeLayoutComponent(final Component comp) {
// not used
}
/**
* Not used.
*
* @param name
* the component name.
* @param comp
* the component.
*/
public void addLayoutComponent(final String name, final Component comp) {
// not used
}
/**
* Not used.
*
* @param name
* the component name.
* @param comp
* the component.
*/
public void removeLayoutComponent(final String name, final Component comp) {
// not used
}
}
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