| /* Panel.java -- Simple container object |
| Copyright (C) 1999, 2002, 2004, 2005 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 java.awt; |
| |
| import javax.accessibility.Accessible; |
| import javax.accessibility.AccessibleContext; |
| import javax.accessibility.AccessibleRole; |
| |
| /** |
| * A panel is a simple container class. It's default layout is the |
| * <code>FlowLayout</code> manager. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Eric Blake (ebb9@email.byu.edu) |
| * @see FlowLayout |
| * @since 1.0 |
| * @status updated to 1.4 |
| */ |
| public class Panel extends Container implements Accessible |
| { |
| /** |
| * Compatible with JDK 1.0+. |
| */ |
| private static final long serialVersionUID = -2728009084054400034L; |
| |
| /** The cached accessible context. */ |
| private transient AccessibleContext context; |
| |
| /** Flag set when the first system-requested paint event is |
| dispatched. */ |
| private transient boolean initialSystemUpdateDone; |
| |
| /** Flag set when the first application-requested paint event is |
| consumed. */ |
| private transient boolean initialUpdateConsumed; |
| |
| /* |
| * The number used to generate the name returned by getName. |
| */ |
| private static transient long next_panel_number; |
| |
| /** |
| * Initializes a new instance of <code>Panel</code> that has a default |
| * layout manager of <code>FlowLayout</code>. |
| */ |
| public Panel() |
| { |
| this(new FlowLayout()); |
| } |
| |
| /** |
| * Initializes a new instance of <code>Panel</code> with the specified |
| * layout manager. |
| * |
| * @param layoutManager the layout manager for this object |
| * @since 1.1 |
| */ |
| public Panel(LayoutManager layoutManager) |
| { |
| setLayout(layoutManager); |
| } |
| |
| /** |
| * Notifies this object to create its native peer. |
| * |
| * @see #isDisplayable() |
| * @see #removeNotify() |
| */ |
| public void addNotify() |
| { |
| if (peer == null) |
| peer = getToolkit().createPanel(this); |
| super.addNotify(); |
| } |
| |
| /** |
| * Gets the AccessibleContext associated with this panel, creating one if |
| * necessary. This always returns an instance of {@link AccessibleAWTPanel}. |
| * |
| * @return the accessibility context of this panel |
| * @since 1.3 |
| */ |
| public AccessibleContext getAccessibleContext() |
| { |
| if (context == null) |
| context = new AccessibleAWTPanel(); |
| return context; |
| } |
| |
| /** |
| * This class provides accessibility support for Panels, and is the |
| * runtime type returned by {@link #getAccessibleContext()}. |
| * |
| * @author Eric Blake (ebb9@email.byu.edu) |
| * @since 1.3 |
| */ |
| protected class AccessibleAWTPanel extends AccessibleAWTContainer |
| { |
| /** |
| * Compatible with JDK 1.4+. |
| */ |
| private static final long serialVersionUID = -6409552226660031050L; |
| |
| /** |
| * The default constructor. |
| */ |
| protected AccessibleAWTPanel() |
| { |
| } |
| |
| /** |
| * Get the role of this accessible object, a panel. |
| * |
| * @return the role of the object |
| * @see AccessibleRole#PANEL |
| */ |
| public AccessibleRole getAccessibleRole() |
| { |
| return AccessibleRole.PANEL; |
| } |
| } |
| |
| /** |
| * Generate a unique name for this panel. |
| * |
| * @return A unique name for this panel. |
| */ |
| String generateName () |
| { |
| return "panel" + getUniqueLong (); |
| } |
| |
| private static synchronized long getUniqueLong () |
| { |
| return next_panel_number++; |
| } |
| } |