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
|
// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROME_BROWSER_GTK_ACCESSIBILITY_EVENT_ROUTER_GTK_H_
#define CHROME_BROWSER_GTK_ACCESSIBILITY_EVENT_ROUTER_GTK_H_
#include <gtk/gtk.h>
#include <string>
#include <vector>
#include "base/basictypes.h"
#include "base/hash_tables.h"
#include "base/singleton.h"
#include "chrome/common/accessibility_events.h"
class Profile;
// Allows us to use (GtkWidget*) in a hash_map with gcc.
namespace __gnu_cxx {
template<>
struct hash<GtkWidget*> {
size_t operator()(GtkWidget* widget) const {
return reinterpret_cast<size_t>(widget);
}
};
} // namespace __gnu_cxx
// Singleton class that adds a signal emission hook to many gtk events, and
// then sends an accessibility notification whenever a relevant event is
// sent to an accessible control.
//
// Gtk widgets are not accessible by default. When you register a root widget,
// that widget and all of its descendants will start sending accessibility
// event notifications. You can then override the default behavior for
// specific descendants using other methods.
//
// You can use Profile::PauseAccessibilityEvents to prevent a flurry
// of accessibility events when a window is being created or initialized.
class AccessibilityEventRouter {
public:
// Internal information about a particular widget to override the
// information we get directly from gtk.
struct WidgetInfo {
// If nonempty, will use this name instead of the widget's label.
std::string name;
// If true, will ignore this widget and not send accessibility events.
bool ignore;
};
// Get the single instance of this class.
static AccessibilityEventRouter* GetInstance();
// Start sending accessibility events for this widget and all of its
// descendants. Notifications will go to the specified profile.
void AddRootWidget(GtkWidget* root_widget, Profile* profile);
// Stop sending accessibility events for this widget and all of its
// descendants.
void RemoveRootWidget(GtkWidget* root_widget);
// Don't send any events for this widget.
void IgnoreWidget(GtkWidget* widget);
// Use the following string as the name of this widget, instead of the
// gtk label associated with the widget.
void SetWidgetName(GtkWidget* widget, std::string name);
// Forget all information about this widget.
void RemoveWidget(GtkWidget* widget);
//
// The following methods are only for use by gtk signal handlers.
//
// Returns true if this widget is a descendant of one of our registered
// root widgets and not in the set of ignored widgets. If |profile| is
// not null, return the profile where notifications associated with this
// widget should be sent.
bool IsWidgetAccessible(GtkWidget* widget, Profile** profile);
// Return the name of a widget.
std::string GetWidgetName(GtkWidget* widget);
// Called by the signal handler. Checks the type of the widget and
// calls one of the more specific Send*Notification methods, below.
void DispatchAccessibilityNotification(
GtkWidget* widget, NotificationType type);
// Each of these methods constructs an AccessibilityControlInfo object
// and sends a notification of a specific accessibility event.
void SendRadioButtonNotification(
GtkWidget* widget, NotificationType type, Profile* profile);
void SendCheckboxNotification(
GtkWidget* widget, NotificationType type, Profile* profile);
void SendButtonNotification(
GtkWidget* widget, NotificationType type, Profile* profile);
void SendTextBoxNotification(
GtkWidget* widget, NotificationType type, Profile* profile);
void SendTabNotification(
GtkWidget* widget, NotificationType type, Profile* profile);
void InstallEventListeners();
void RemoveEventListeners();
private:
AccessibilityEventRouter();
virtual ~AccessibilityEventRouter() {}
friend struct DefaultSingletonTraits<AccessibilityEventRouter>;
// The set of all root widgets; only descendants of these will generate
// accessibility notifications.
base::hash_map<GtkWidget*, Profile*> root_widget_profile_map_;
// Extra information about specific widgets.
base::hash_map<GtkWidget*, WidgetInfo> widget_info_map_;
// Installed event listener hook ids so we can remove them later.
gulong focus_hook_;
gulong click_hook_;
gulong toggle_hook_;
gulong switch_page_hook_;
std::vector<gulong> event_listener_hook_ids_;
};
#endif // CHROME_BROWSER_GTK_ACCESSIBILITY_EVENT_ROUTER_GTK_H_
|
