1 /*
2  * This file is part of the LibreOffice project.
3  *
4  * This Source Code Form is subject to the terms of the Mozilla Public
5  * License, v. 2.0. If a copy of the MPL was not distributed with this
6  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
7  *
8  * This file incorporates work covered by the following license notice:
9  *
10  *   Licensed to the Apache Software Foundation (ASF) under one or more
11  *   contributor license agreements. See the NOTICE file distributed
12  *   with this work for additional information regarding copyright
13  *   ownership. The ASF licenses this file to you under the Apache
14  *   License, Version 2.0 (the "License"); you may not use this file
15  *   except in compliance with the License. You may obtain a copy of
16  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
17  */
18 
19 import com.sun.star.accessibility.*;
20 
21 /** Objects of this class (usually one, singleton?) listen to accessible
22     events of all objects in all trees.
23 */
24 public class EventListener
25 {
26     private boolean mbVerbose = false;
27 
EventListener(AccessibilityTreeModel aTreeModel)28     public EventListener (AccessibilityTreeModel aTreeModel)
29     {
30         maTreeModel = aTreeModel;
31     }
32 
33 
34     /** This method handles accessibility objects that are being disposed.
35      */
disposing(XAccessibleContext xContext)36     public void disposing (XAccessibleContext xContext)
37     {
38         if (mbVerbose)
39             System.out.println("disposing " + xContext);
40         maTreeModel.removeNode (xContext);
41     }
42 
43     /** This method is called from accessible objects that broadcast
44         modifications of themselves or from their children.  The event is
45         processed only, except printing some messages, if the tree is not
46         locked.  It should be locked during changes to its internal
47         structure like expanding nodes.
48     */
notifyEvent(AccessibleEventObject aEvent)49     public void notifyEvent (AccessibleEventObject aEvent)
50     {
51         EventHandler aHandler;
52 
53         switch (aEvent.EventId)
54         {
55             case AccessibleEventId.CHILD:
56                 aHandler = new ChildEventHandler (aEvent, maTreeModel);
57                 break;
58 
59             case AccessibleEventId.BOUNDRECT_CHANGED:
60             case AccessibleEventId.VISIBLE_DATA_CHANGED:
61                 aHandler = new GeometryEventHandler (aEvent, maTreeModel);
62                 break;
63 
64 
65             case AccessibleEventId.NAME_CHANGED:
66             case AccessibleEventId.DESCRIPTION_CHANGED:
67             case AccessibleEventId.STATE_CHANGED:
68             case AccessibleEventId.SELECTION_CHANGED:
69                 aHandler = new ContextEventHandler (aEvent, maTreeModel);
70                 break;
71 
72             case AccessibleEventId.TABLE_MODEL_CHANGED:
73             case AccessibleEventId.TABLE_CAPTION_CHANGED:
74             case AccessibleEventId.TABLE_COLUMN_DESCRIPTION_CHANGED:
75             case AccessibleEventId.TABLE_COLUMN_HEADER_CHANGED:
76             case AccessibleEventId.TABLE_ROW_DESCRIPTION_CHANGED:
77             case AccessibleEventId.TABLE_ROW_HEADER_CHANGED:
78             case AccessibleEventId.TABLE_SUMMARY_CHANGED:
79                 aHandler = new TableEventHandler (aEvent, maTreeModel);
80                 break;
81 
82             case AccessibleEventId.ACTION_CHANGED:
83             case AccessibleEventId.HYPERTEXT_CHANGED:
84             case AccessibleEventId.ACTIVE_DESCENDANT_CHANGED:
85             case AccessibleEventId.CARET_CHANGED:
86             case AccessibleEventId.TEXT_CHANGED:
87             case AccessibleEventId.VALUE_CHANGED:
88                 aHandler = new EventHandler (aEvent, maTreeModel);
89                 break;
90 
91             default:
92                 aHandler = null;
93                 break;
94         }
95 
96         if (aHandler == null)
97             System.out.println ("    unhandled event");
98         else
99         {
100             if (mbVerbose)
101                 aHandler.Print (System.out);
102             aHandler.Process ();
103         }
104     }
105 
106 
107     private final AccessibilityTreeModel maTreeModel;
108 }
109