1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/**************************************************************
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*************************************************************/
import com.sun.star.accessibility.XAccessible;
import com.sun.star.accessibility.XAccessibleEventListener;
import com.sun.star.accessibility.AccessibleEventObject;
import com.sun.star.lang.EventObject;
import com.sun.star.awt.XTopWindowListener;
import com.sun.star.uno.UnoRuntime;
import java.util.LinkedList;
/** This class acts as a proxy for the simple screen reader. It waits for
two types of events:
1. Accessibility events signal modifications concerning accessibility
objects.
2. Top window events inform the listener about new or removed windows.
This class exists because events had to be handled in a seperate thread
to avoid dead locks: The thread that receives an event must no call back
to the Office directly.
Soon this should not be necessary anymore. There is now a flag which
switches between synchronous and asynchronous callbacks.
All reveived events are eventually forwarded to the actual listener. In
this way it decouples the Office from the listener.
*/
class EventListenerProxy
implements Runnable, XAccessibleEventListener, XTopWindowListener
{
public EventListenerProxy (EventHandler aListener)
{
maListener = aListener;
mbAsynchron = true;
if (mbAsynchron)
{
maEventQueue = new LinkedList();
new Thread (this, "EventListenerProxy").start();
}
}
private void addEvent (Runnable aEventObject)
{
if (mbAsynchron)
synchronized (maEventQueue)
{
maEventQueue.addLast (aEventObject);
// Tell the queue that there is a new event in the queue.
maEventQueue.notify();
}
else
{
System.out.println ("running " + aEventObject);
aEventObject.run();
System.out.println (" done");
}
}
/** In an infinite loop, check for events to deliver, then wait on lock
(which will be notified when new events arrive)
*/
public void run ()
{
while (true)
{
// Process all events that are currently in the queue.
Runnable aEvent;
do
{
synchronized (maEventQueue)
{
if (maEventQueue.size() > 0)
aEvent = (Runnable)maEventQueue.removeFirst();
else
aEvent = null;
}
if (aEvent != null)
{
try
{
aEvent.run();
}
catch (Throwable aException)
{
MessageArea.println(
"Exception during event delivery: " + aException);
aException.printStackTrace();
}
}
}
while (aEvent != null);
// Now that the queue is empty go to sleep again.
try
{
synchronized (maEventQueue)
{
maEventQueue.wait();
}
}
catch (Exception aException)
{
// Ignore this exception since there is not much
// that we can do about it.
}
}
}
public void disposing( final EventObject aEvent)
{
addEvent (new Runnable()
{
public void run()
{
maListener.disposing (aEvent);
}
} );
}
public void notifyEvent (final AccessibleEventObject aEvent)
{
addEvent (
new Runnable()
{
public void run()
{
maListener.notifyEvent (aEvent);
}
} );
}
public void windowOpened (final com.sun.star.lang.EventObject aEvent)
{
addEvent (
new Runnable()
{
public void run()
{
maListener.windowOpened (
(XAccessible) UnoRuntime.queryInterface(
XAccessible.class,
aEvent.Source));
}
} );
}
public void windowClosing (final com.sun.star.lang.EventObject aEvent)
{
// Ignored.
}
public void windowClosed (final com.sun.star.lang.EventObject aEvent)
{
addEvent (
new Runnable()
{
public void run()
{
maListener.windowClosed (
(XAccessible) UnoRuntime.queryInterface(
XAccessible.class,
aEvent.Source));
}
} );
}
public void windowMinimized (com.sun.star.lang.EventObject aEvent)
{
// Ignored.
}
public void windowNormalized (com.sun.star.lang.EventObject aEvent)
{
// Ignored.
}
public void windowActivated (com.sun.star.lang.EventObject aEvent)
{
// Ignored.
}
public void windowDeactivated (com.sun.star.lang.EventObject aEvent)
{
// Ignored.
}
/** The queue of event objects, LinkedList<Runnable>.
The queue object will also serve as lock for the consumer/producer type
syncronization.
*/
private LinkedList maEventQueue;
/** This is the actual listener that the events will eventually forwarded to.
*/
private EventHandler maListener;
/** This flag determines whether event forwarding is done asynchroniously
or synchroniously.
*/
private boolean mbAsynchron;
}
|
