/* MenuBar.java -- An AWT menu bar class
   Copyright (C) 1999 Free Software Foundation, Inc.

This file is part of the non-peer AWT libraries of GNU Classpath.

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

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 Library General Public License for more details.

You should have received a copy of the GNU Library General Public License
along with this library; if not, write to the Free Software Foundation
Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307 USA. */


package java.awt;

import java.awt.peer.MenuBarPeer;
import java.awt.peer.MenuComponentPeer;

import java.io.Serializable;
import java.util.Enumeration;
import java.util.Vector;

/**
  * This class implements a menu bar in the AWT system.
  *
  * @author Aaron M. Renn (arenn@urbanophile.com)
  */
public class MenuBar extends MenuComponent implements MenuContainer, Serializable
{

/*
 * Static Variables
 */

// Serialization Constant
private static final long serialVersionUID = -4930327919388951260L;

/*************************************************************************/

/*
 * Instance Variables
 */

/**
  * @serial The menu used for providing help information
  */
private Menu helpMenu;

/**
  * @serial The menus contained in this menu bar.
  */
private Vector menus = new Vector();

/*************************************************************************/

/*
 * Constructors
 */

/**
  * Initializes a new instance of <code>MenuBar</code>.
  */
public
MenuBar()
{
}

/*************************************************************************/

/*
 * Instance Methods
 */

/**
  * Returns the help menu for this menu bar.  This may be <code>null</code>.
  *
  * @return The help menu for this menu bar.
  */
public Menu
getHelpMenu()
{
  return(helpMenu);
}

/*************************************************************************/

/**
  * Sets the help menu for this menu bar.
  *
  * @param helpMenu The new help menu for this menu bar.
  */
public synchronized void
setHelpMenu(Menu helpMenu)
{
  // FIXME: Does this need to be added to the vector of items?
  this.helpMenu = helpMenu;

  MenuBarPeer mbp = (MenuBarPeer)getPeer();
  if (mbp != null)
    mbp.addHelpMenu(helpMenu);
}

/*************************************************************************/

/**
  * Adds the specified menu to this menu bar.
  *
  * @param menu The menu to add.
  *
  * @return The menu that was added.
  */
public synchronized Menu
add(Menu menu)
{
  menus.addElement(menu);

  MenuBarPeer mbp = (MenuBarPeer)getPeer();
  if (mbp != null)
    mbp.addMenu(menu);

  return(menu);
}

/*************************************************************************/

/**
  * Removes the menu at the specified index.
  *
  * @param index The index of the menu to remove from the menu bar.
  */
public synchronized void
remove(int index)
{
  menus.removeElementAt(index);

  MenuBarPeer mbp = (MenuBarPeer)getPeer();
  if (mbp != null)
    mbp.delMenu(index);
}

/*************************************************************************/

/**
  * Removes the specified menu from the menu bar.
  *
  * @param menu The menu to remove from the menu bar.
  */
public void
remove(MenuComponent menu)
{
  int index = menus.indexOf(menu);
  if (index == -1)
    return;

  remove(index);
}

/*************************************************************************/

/**
  * Returns the number of elements in this menu bar.
  *
  * @return The number of elements in the menu bar.
  */
public int
getMenuCount()
{
  // FIXME: How does the help menu fit in here?
  return(menus.size());
}

/*************************************************************************/

/**
  * Returns the number of elements in this menu bar.
  *
  * @return The number of elements in the menu bar.
  *
  * @deprecated This method is deprecated in favor of <code>getMenuCount()</code>.
  */
public int
countMenus()
{
  return(getMenuCount());
}

/*************************************************************************/

/**
  * Returns the menu at the specified index.
  *
  * @return The requested menu.
  *
  * @exception ArrayIndexOutOfBoundsException If the index is not valid.
  */
public Menu
getMenu(int index)
{
  return((Menu)menus.elementAt(index));
}

/*************************************************************************/

/**
  * Creates this object's native peer.
  */
public void
addNotify()
{
  if (getPeer() == null)
    setPeer((MenuComponentPeer)getToolkit().createMenuBar(this));
}

/*************************************************************************/

/**
  * Destroys this object's native peer.
  */
public void
removeNotify()
{
  super.removeNotify();
}

/*************************************************************************/

/**
  * Returns a list of all shortcuts for the menus in this menu bar.
  *
  * @return A list of all shortcuts for the menus in this menu bar.
  */
public synchronized Enumeration
shortcuts()
{
  Vector shortcuts = new Vector();
  Enumeration e = menus.elements();

  while (e.hasMoreElements())
    {
      Menu menu = (Menu)e.nextElement();
      if (menu.getShortcut() != null)
        shortcuts.addElement(menu.getShortcut());
    }

  return(shortcuts.elements());
}

/*************************************************************************/

/**
  * Returns the menu item for the specified shortcut, or <code>null</code>
  * if no such item exists.
  *
  * @param shortcut The shortcut to return the menu item for.
  *
  * @return The menu item for the specified shortcut.
  */
public MenuItem
getShortcutMenuItem(MenuShortcut shortcut)
{
  Enumeration e = menus.elements();

  while (e.hasMoreElements())
    {
      Menu menu = (Menu)e.nextElement();
      MenuShortcut s = menu.getShortcut();
      if ((s != null) && (s.equals(shortcut)))
        return(menu);
    }

  return(null);
}

/*************************************************************************/

/**
  * Deletes the specified menu shortcut.
  *
  * @param shortcut The shortcut to delete.
  */
public void
deleteShortcut(MenuShortcut shortcut)
{
  MenuItem mi = getShortcutMenuItem(shortcut);
  if (mi != null)
    mi.setShortcut(null);
}

} // class MenuBar