| /* |
| * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.awt.event; |
| |
| import java.awt.AWTEvent; |
| import java.awt.Component; |
| import java.awt.Container; |
| |
| /** |
| * An event which indicates a change to the <code>Component</code> |
| * hierarchy to which <code>Component</code> belongs. |
| * <ul> |
| * <li>Hierarchy Change Events (HierarchyListener) |
| * <ul> |
| * <li> addition of an ancestor |
| * <li> removal of an ancestor |
| * <li> hierarchy made displayable |
| * <li> hierarchy made undisplayable |
| * <li> hierarchy shown on the screen (both visible and displayable) |
| * <li> hierarchy hidden on the screen (either invisible or undisplayable) |
| * </ul> |
| * <li>Ancestor Reshape Events (HierarchyBoundsListener) |
| * <ul> |
| * <li> an ancestor was resized |
| * <li> an ancestor was moved |
| * </ul> |
| * </ul> |
| * <p> |
| * Hierarchy events are provided for notification purposes ONLY. |
| * The AWT will automatically handle changes to the hierarchy internally so |
| * that GUI layout and displayability works properly regardless of whether a |
| * program is receiving these events or not. |
| * <p> |
| * This event is generated by a Container object (such as a Panel) when the |
| * Container is added, removed, moved, or resized, and passed down the |
| * hierarchy. It is also generated by a Component object when that object's |
| * <code>addNotify</code>, <code>removeNotify</code>, <code>show</code>, or |
| * <code>hide</code> method is called. The {@code ANCESTOR_MOVED} and |
| * {@code ANCESTOR_RESIZED} |
| * events are dispatched to every <code>HierarchyBoundsListener</code> or |
| * <code>HierarchyBoundsAdapter</code> object which registered to receive |
| * such events using the Component's <code>addHierarchyBoundsListener</code> |
| * method. (<code>HierarchyBoundsAdapter</code> objects implement the <code> |
| * HierarchyBoundsListener</code> interface.) The {@code HIERARCHY_CHANGED} events are |
| * dispatched to every <code>HierarchyListener</code> object which registered |
| * to receive such events using the Component's <code>addHierarchyListener |
| * </code> method. Each such listener object gets this <code>HierarchyEvent |
| * </code> when the event occurs. |
| * <p> |
| * An unspecified behavior will be caused if the {@code id} parameter |
| * of any particular {@code HierarchyEvent} instance is not |
| * in the range from {@code HIERARCHY_FIRST} to {@code HIERARCHY_LAST}. |
| * <br> |
| * The {@code changeFlags} parameter of any {@code HierarchyEvent} instance takes one of the following |
| * values: |
| * <ul> |
| * <li> {@code HierarchyEvent.PARENT_CHANGED} |
| * <li> {@code HierarchyEvent.DISPLAYABILITY_CHANGED} |
| * <li> {@code HierarchyEvent.SHOWING_CHANGED} |
| * </ul> |
| * Assigning the value different from listed above will cause unspecified behavior. |
| * |
| * @author David Mendenhall |
| * @see HierarchyListener |
| * @see HierarchyBoundsAdapter |
| * @see HierarchyBoundsListener |
| * @since 1.3 |
| */ |
| public class HierarchyEvent extends AWTEvent { |
| /* |
| * serialVersionUID |
| */ |
| private static final long serialVersionUID = -5337576970038043990L; |
| |
| /** |
| * Marks the first integer id for the range of hierarchy event ids. |
| */ |
| public static final int HIERARCHY_FIRST = 1400; // 1300 used by sun.awt.windows.ModalityEvent |
| |
| /** |
| * The event id indicating that modification was made to the |
| * entire hierarchy tree. |
| */ |
| public static final int HIERARCHY_CHANGED = HIERARCHY_FIRST; |
| |
| /** |
| * The event id indicating an ancestor-Container was moved. |
| */ |
| public static final int ANCESTOR_MOVED = 1 + HIERARCHY_FIRST; |
| |
| /** |
| * The event id indicating an ancestor-Container was resized. |
| */ |
| public static final int ANCESTOR_RESIZED = 2 + HIERARCHY_FIRST; |
| |
| /** |
| * Marks the last integer id for the range of ancestor event ids. |
| */ |
| public static final int HIERARCHY_LAST = ANCESTOR_RESIZED; |
| |
| /** |
| * A change flag indicates that the <code>HIERARCHY_CHANGED</code> event |
| * was generated by a reparenting operation. |
| */ |
| public static final int PARENT_CHANGED = 0x1; |
| |
| /** |
| * A change flag indicates that the <code>HIERARCHY_CHANGED</code> event |
| * was generated due to the changing of the hierarchy displayability. |
| * To discern the |
| * current displayability of the hierarchy, call the |
| * <code>Component.isDisplayable</code> method. Displayability changes occur |
| * in response to explicit or implicit calls of the |
| * <code>Component.addNotify</code> and |
| * <code>Component.removeNotify</code> methods. |
| * |
| * @see java.awt.Component#isDisplayable() |
| * @see java.awt.Component#addNotify() |
| * @see java.awt.Component#removeNotify() |
| */ |
| public static final int DISPLAYABILITY_CHANGED = 0x2; |
| |
| /** |
| * A change flag indicates that the <code>HIERARCHY_CHANGED</code> event |
| * was generated due to the changing of the hierarchy showing state. |
| * To discern the |
| * current showing state of the hierarchy, call the |
| * <code>Component.isShowing</code> method. Showing state changes occur |
| * when either the displayability or visibility of the |
| * hierarchy occurs. Visibility changes occur in response to explicit |
| * or implicit calls of the <code>Component.show</code> and |
| * <code>Component.hide</code> methods. |
| * |
| * @see java.awt.Component#isShowing() |
| * @see java.awt.Component#addNotify() |
| * @see java.awt.Component#removeNotify() |
| * @see java.awt.Component#show() |
| * @see java.awt.Component#hide() |
| */ |
| public static final int SHOWING_CHANGED = 0x4; |
| |
| Component changed; |
| Container changedParent; |
| long changeFlags; |
| |
| /** |
| * Constructs an <code>HierarchyEvent</code> object to identify a |
| * change in the <code>Component</code> hierarchy. |
| * <p>This method throws an |
| * <code>IllegalArgumentException</code> if <code>source</code> |
| * is <code>null</code>. |
| * |
| * @param source The <code>Component</code> object that |
| * originated the event |
| * @param id An integer indicating the type of event. |
| * For information on allowable values, see |
| * the class description for {@link HierarchyEvent} |
| * @param changed The <code>Component</code> at the top of |
| * the hierarchy which was changed |
| * @param changedParent The parent of the <code>changed</code> component. |
| * This |
| * may be the parent before or after the |
| * change, depending on the type of change |
| * @throws IllegalArgumentException if <code>source</code> is {@code null} |
| * @see #getSource() |
| * @see #getID() |
| * @see #getChanged() |
| * @see #getChangedParent() |
| */ |
| public HierarchyEvent(Component source, int id, Component changed, |
| Container changedParent) { |
| super(source, id); |
| this.changed = changed; |
| this.changedParent = changedParent; |
| } |
| |
| /** |
| * Constructs an <code>HierarchyEvent</code> object to identify |
| * a change in the <code>Component</code> hierarchy. |
| * <p> This method throws an |
| * <code>IllegalArgumentException</code> if <code>source</code> |
| * is <code>null</code>. |
| * |
| * @param source The <code>Component</code> object that |
| * originated the event |
| * @param id An integer indicating the type of event. |
| * For information on allowable values, see |
| * the class description for {@link HierarchyEvent} |
| * @param changed The <code>Component</code> at the top |
| * of the hierarchy which was changed |
| * @param changedParent The parent of the <code>changed</code> component. |
| * This |
| * may be the parent before or after the |
| * change, depending on the type of change |
| * @param changeFlags A bitmask which indicates the type(s) of |
| * the <code>HIERARCHY_CHANGED</code> events |
| * represented in this event object. |
| * For information on allowable values, see |
| * the class description for {@link HierarchyEvent} |
| * @throws IllegalArgumentException if <code>source</code> is null |
| * @see #getSource() |
| * @see #getID() |
| * @see #getChanged() |
| * @see #getChangedParent() |
| * @see #getChangeFlags() |
| */ |
| public HierarchyEvent(Component source, int id, Component changed, |
| Container changedParent, long changeFlags) { |
| super(source, id); |
| this.changed = changed; |
| this.changedParent = changedParent; |
| this.changeFlags = changeFlags; |
| } |
| |
| /** |
| * Returns the originator of the event. |
| * |
| * @return the <code>Component</code> object that originated |
| * the event, or <code>null</code> if the object is not a |
| * <code>Component</code>. |
| */ |
| public Component getComponent() { |
| return (source instanceof Component) ? (Component)source : null; |
| } |
| |
| /** |
| * Returns the Component at the top of the hierarchy which was |
| * changed. |
| * |
| * @return the changed Component |
| */ |
| public Component getChanged() { |
| return changed; |
| } |
| |
| /** |
| * Returns the parent of the Component returned by <code> |
| * getChanged()</code>. For a HIERARCHY_CHANGED event where the |
| * change was of type PARENT_CHANGED via a call to <code> |
| * Container.add</code>, the parent returned is the parent |
| * after the add operation. For a HIERARCHY_CHANGED event where |
| * the change was of type PARENT_CHANGED via a call to <code> |
| * Container.remove</code>, the parent returned is the parent |
| * before the remove operation. For all other events and types, |
| * the parent returned is the parent during the operation. |
| * |
| * @return the parent of the changed Component |
| */ |
| public Container getChangedParent() { |
| return changedParent; |
| } |
| |
| /** |
| * Returns a bitmask which indicates the type(s) of |
| * HIERARCHY_CHANGED events represented in this event object. |
| * The bits have been bitwise-ored together. |
| * |
| * @return the bitmask, or 0 if this is not an HIERARCHY_CHANGED |
| * event |
| */ |
| public long getChangeFlags() { |
| return changeFlags; |
| } |
| |
| /** |
| * Returns a parameter string identifying this event. |
| * This method is useful for event-logging and for debugging. |
| * |
| * @return a string identifying the event and its attributes |
| */ |
| public String paramString() { |
| String typeStr; |
| switch(id) { |
| case ANCESTOR_MOVED: |
| typeStr = "ANCESTOR_MOVED ("+changed+","+changedParent+")"; |
| break; |
| case ANCESTOR_RESIZED: |
| typeStr = "ANCESTOR_RESIZED ("+changed+","+changedParent+")"; |
| break; |
| case HIERARCHY_CHANGED: { |
| typeStr = "HIERARCHY_CHANGED ("; |
| boolean first = true; |
| if ((changeFlags & PARENT_CHANGED) != 0) { |
| first = false; |
| typeStr += "PARENT_CHANGED"; |
| } |
| if ((changeFlags & DISPLAYABILITY_CHANGED) != 0) { |
| if (first) { |
| first = false; |
| } else { |
| typeStr += ","; |
| } |
| typeStr += "DISPLAYABILITY_CHANGED"; |
| } |
| if ((changeFlags & SHOWING_CHANGED) != 0) { |
| if (first) { |
| first = false; |
| } else { |
| typeStr += ","; |
| } |
| typeStr += "SHOWING_CHANGED"; |
| } |
| if (!first) { |
| typeStr += ","; |
| } |
| typeStr += changed + "," + changedParent + ")"; |
| break; |
| } |
| default: |
| typeStr = "unknown type"; |
| } |
| return typeStr; |
| } |
| } |
