path: root/libjava/javax/swing/plaf/basic/BasicSeparatorUI.java

/* BasicSeparatorUI.java
   Copyright (C) 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */

package javax.swing.plaf.basic;

import java.awt.Dimension;
import java.awt.Color;
import java.awt.Rectangle;
import java.awt.Graphics;
import java.awt.Insets;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.SeparatorUI;
import javax.swing.UIDefaults;
import javax.swing.UIManager;
import javax.swing.JComponent;
import javax.swing.JSeparator;
import javax.swing.SwingUtilities;

/**
 * The Basic Look and Feel UI delegate for JSeparator.
 */
public class BasicSeparatorUI extends SeparatorUI
{
  /** The shadow color. */
  protected Color shadow;

  /** The highlight color. */
  protected Color highlight;

  /**
   * Creates a new UI delegate for the given JComponent.
   *
   * @param c The JComponent to create a delegate for.
   *
   * @return A new BasicSeparatorUI.
   */
  public static ComponentUI createUI(JComponent c)
  {
    return new BasicSeparatorUI();
  }

  /**
   * This method installs the UI for the given JComponent.
   * This can include installing defaults, listeners, and
   * initializing any instance data.
   *
   * @param c The JComponent that is having this UI installed.
   */
  public void installUI(JComponent c)
  {
    super.installUI(c);

    if (c instanceof JSeparator)
      {
	JSeparator s = (JSeparator) c;

	installDefaults(s);
	installListeners(s);
      }
  }

  /**
   * Uninstalls the UI for the given JComponent. This
   * method reverses what was done when installing
   * the UI on the JComponent.
   *
   * @param c The JComponent that is having this UI uninstalled.
   */
  public void uninstallUI(JComponent c)
  {
    if (c instanceof JSeparator)
      {
	JSeparator s = (JSeparator) c;

	uninstallListeners(s);
	uninstallDefaults(s);
      }
  }

  /**
   * This method installs the defaults that are given by
   * the Basic Look and Feel.
   *
   * @param s The JSeparator that is being installed.
   */
  protected void installDefaults(JSeparator s)
  {
    UIDefaults defaults = UIManager.getLookAndFeelDefaults();

    shadow = defaults.getColor("Separator.shadow");
    highlight = defaults.getColor("Separator.highlight");
    s.setOpaque(true);
  }

  /**
   * This method removes the defaults that were given
   * by the Basic Look and Feel.
   *
   * @param s The JSeparator that is being uninstalled.
   */
  protected void uninstallDefaults(JSeparator s)
  {
    shadow = null;
    highlight = null;
  }

  /**
   * This method installs any listeners that need
   * to be attached to the JSeparator or any of its 
   * components.
   *
   * @param s The JSeparator that is being installed.
   */
  protected void installListeners(JSeparator s)
  {
    // Separators don't receive events.
  }

  /**
   * This method uninstalls any listeners that
   * were installed during the install UI process.
   *
   * @param s The JSeparator that is being uninstalled.
   */
  protected void uninstallListeners(JSeparator s)
  {
    // Separators don't receive events.  
  }

  /**
   * The separator is made of two lines. The top line will be 
   * the highlight color (or left line if it's vertical). The bottom 
   * or right line will be the shadow color. The two lines will 
   * be centered inside the bounds box. If the separator is horizontal, 
   * then it will be vertically centered, or if it's vertical, it will 
   * be horizontally centered.
   *
   * @param g The Graphics object to paint with
   * @param c The JComponent to paint.
   */
  public void paint(Graphics g, JComponent c)
  {
    Rectangle r = new Rectangle();
    SwingUtilities.calculateInnerArea(c, r);
    Color saved = g.getColor();
    
    int midAB = r.width / 2 + r.x;
    int midAD = r.height / 2 + r.y;
  
    JSeparator s;
    if (c instanceof JSeparator)
      s = (JSeparator) c;
    else
      return;
      
    if (s.getOrientation() == JSeparator.HORIZONTAL)
    {    
      g.setColor(highlight);
      g.drawLine(r.x, midAD, r.x + r.width, midAD);
      
      g.setColor(shadow);
      g.drawLine(r.x, midAD + 1, r.x + r.width, midAD + 1);
    }
    else
    {
      g.setColor(highlight);
      g.drawLine(midAB, r.y, midAB, r.y + r.height);
      
      g.setColor(shadow);
      g.drawLine(midAB + 1, r.y, midAB + 1, r.y + r.height);
    }
  }

  /**
   * This method returns the preferred size of the 
   * JComponent.
   *
   * @param c The JComponent to measure.
   *
   * @return The preferred size.
   */
  public Dimension getPreferredSize(JComponent c)
  {
    Dimension dims = new Dimension(0, 0);
    Insets insets = c.getInsets();

    if (c instanceof JSeparator)
      {
	JSeparator s = (JSeparator) c;

	if (s.getOrientation() == JSeparator.HORIZONTAL)
	{
	  dims.height = 2;
	  dims.width = 40;
	}
	else
	{
	  dims.width = 2;
	  dims.height = 40;
	}
      }
    dims.width += insets.left + insets.right;
    dims.height += insets.top + insets.bottom;
    
    return dims;
  }

  /**
   * This method returns the minimum size of the
   * JComponent.
   *
   * @param c The JComponent to measure.
   *
   * @return The minimum size.
   */
  public Dimension getMinimumSize(JComponent c)
  {
    return getPreferredSize(c);
  }

  /**
   * This method returns the maximum size of the
   * JComponent.
   *
   * @param c The JComponent to measure.
   *
   * @return The maximum size.
   */
  public Dimension getMaximumSize(JComponent c)
  {
    return getPreferredSize(c);
  }
}