/* ComboBoxUI.java --
   Copyright (C) 2002, 2003 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
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 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
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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
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this exception to your version of the library, but you are not
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package javax.swing.plaf;

import javax.swing.JComboBox;

/**
 * An abstract base class for delegates that implement the pluggable
 * look and feel for a <code>JButton</code>.
 *
 * @see javax.swing.JComboBox
 *
 * @author Andrew Selkirk
 * @author Sascha Brawer (brawer@dandelis.ch)
 */
public abstract class ComboBoxUI extends ComponentUI
{
  /**
   * Constructs a new <code>ComboBoxUI</code>.
   */
  public ComboBoxUI()
  {
    // Nothing to do here.
  }
  
  
  /**
   * Sets the visibility of the popup button.
   *
   * @param c the <code>JComboBox</code> whose popup
   *        is shown or hidden.
   *
   * @param visible <code>true</code> to show the popup, <code>false</code>
   *        to hide it.
   */
  public abstract void setPopupVisible(JComboBox c, boolean visible);


  /**
   * Determines whether the popup button is currently visible.
   *
   * @param c the <code>JComboBox</code> whose popup visibility
   *        is retrieved.
   *
   * @return <code>true</code> if the popup button is currently
   *         visible, <code>false</code> otherwise.
   */
  public abstract boolean isPopupVisible(JComboBox c);
  
  
  /**
   * Determines whether the combo box can receive input focus.
   *
   * @param c <code>JComboBox</code> whose focus traversability
   *        is to be retrieved.
   *
   * @returns <code>true</code> if <code>c</code> can receive
   *          input focus, <code>false</code> otherwise.
   */
  public abstract boolean isFocusTraversable(JComboBox c);
}