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
|
// 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.
#include "ceee/ie/plugin/bho/tool_band_visibility.h"
#include "base/logging.h"
#include "ceee/ie/common/ie_tab_interfaces.h"
#include "ceee/ie/common/ceee_module_util.h"
#include "ceee/ie/plugin/toolband/tool_band.h"
// The ToolBandVisibility class allows us to recover from a number of
// features of IE that can cause our toolband to become invisible
// unexpectedly.
// A brief discussion of toolband visibility in IE.
//
// See MS knowledge base article Q219427 for more detail.
//
// IE does some interesting tricks to cache toolband layout information. One
// side effect of this is that sometimes it can get confused about whether a
// toolband should be shown or not.
//
// In theory all that is needed to recover from this is a call to
// IWebBrowser2::ShowBrowserBar. Unfortunately, there are some
// gotchas.
// It's not easy to tell when IE has refused to display your
// toolband. The only way to be sure is to either call
// ShowBrowserBar on every startup or wait for some reasonable
// time to see if IE showed the toolband and then kick it if it
// didn't.
// In IE6, a single call to ShowBrowserBar is often not enough to
// unhide a hidden toolband. It's sometimes necessary to call
// ShowBrowserBar THREE times (show, then hide, then show) to get
// things into a sane state.
// TODO(cindylau@chromium.org): In IE6, just calling ShowBrowserBar
// will usually cause IE to scrunch our toolband up at the end of
// a line instead of giving it its own line. We can combat this
// by requesting to be shown on our own line, but if we do that
// in all cases we'll anger users who WANT our toolband to share
// a line with others.
// Some other toolbands (notably SnagIt versions 6 and 7) will
// cause toolbands to get hidden when opening a new tab in IE7.
// Visibility must be checked on every new tab and window to be
// sure.
// Calls to ShowBrowserBar are slow and we should avoid them
// whenever possible.
// Calls to ShowBrowserBar should be made from the same UI thread
// responsible for the browser object we use to unhide the
// toolband. Failure to do this can cause the toolband to
// believe it belongs to a different thread than it does.
// TODO(cindylau@chromium.org): IE tracks layout information in the
// registry. When toolbands are added or removed the installing
// toolband MUST clear the registry (badness, including possible
// crashes in IE will result if not). When this layout
// information is cleared all third party toolbands are hidden.
// This code attempts to address all of these issues.
// The core is the VisibilityUtil class.
// When VisibilityUtil::CheckVisibility is called it checks for common
// indicators that a toolband is hidden. If it sees a smoking gun
// it unhides the toolband. Otherwise it creates a notification window and
// a timer. If a toolband doesn't report itself as active for a particular
// browser window before the timer fires it unhides the toolband.
namespace {
const int kVisibilityTimerId = 1;
const DWORD kVisibilityCheckDelay = 2000; // 2 seconds.
} // anonymous namespace
std::set<IUnknown*> ToolBandVisibility::visibility_set_;
CComAutoCriticalSection ToolBandVisibility::visibility_set_crit_;
ToolBandVisibility::ToolBandVisibility()
: web_browser_(NULL) {
}
ToolBandVisibility::~ToolBandVisibility() {
DCHECK(m_hWnd == NULL);
}
void ToolBandVisibility::ReportToolBandVisible(IWebBrowser2* web_browser) {
DCHECK(web_browser);
CComQIPtr<IUnknown, &IID_IUnknown> browser_identity(web_browser);
DCHECK(browser_identity != NULL);
if (browser_identity == NULL)
return;
CComCritSecLock<CComAutoCriticalSection> lock(visibility_set_crit_);
visibility_set_.insert(browser_identity);
}
bool ToolBandVisibility::IsToolBandVisible(IWebBrowser2* web_browser) {
DCHECK(web_browser);
CComQIPtr<IUnknown, &IID_IUnknown> browser_identity(web_browser);
DCHECK(browser_identity != NULL);
if (browser_identity == NULL)
return false;
CComCritSecLock<CComAutoCriticalSection> lock(visibility_set_crit_);
return visibility_set_.count(browser_identity) != 0;
}
void ToolBandVisibility::ClearCachedVisibility(IWebBrowser2* web_browser) {
CComCritSecLock<CComAutoCriticalSection> lock(visibility_set_crit_);
if (web_browser) {
CComQIPtr<IUnknown, &IID_IUnknown> browser_identity(web_browser);
DCHECK(browser_identity != NULL);
if (browser_identity == NULL)
return;
visibility_set_.erase(browser_identity);
} else {
visibility_set_.clear();
}
}
void ToolBandVisibility::CheckToolBandVisibility(IWebBrowser2* web_browser) {
DCHECK(web_browser);
web_browser_ = web_browser;
if (!ceee_module_util::GetOptionToolbandIsHidden() &&
CreateNotificationWindow()) {
SetWindowTimer(kVisibilityTimerId, kVisibilityCheckDelay);
}
}
void ToolBandVisibility::TearDown() {
if (web_browser_ != NULL) {
ClearCachedVisibility(web_browser_);
}
if (m_hWnd != NULL) {
CloseNotificationWindow();
}
}
bool ToolBandVisibility::CreateNotificationWindow() {
return Create(HWND_MESSAGE) != NULL;
}
void ToolBandVisibility::CloseNotificationWindow() {
DestroyWindow();
}
void ToolBandVisibility::SetWindowTimer(UINT timer_id, UINT delay) {
SetTimer(timer_id, delay, NULL);
}
void ToolBandVisibility::KillWindowTimer(UINT timer_id) {
KillTimer(timer_id);
}
void ToolBandVisibility::OnTimer(UINT_PTR nIDEvent) {
DCHECK(nIDEvent == kVisibilityTimerId);
KillWindowTimer(nIDEvent);
if (!IsToolBandVisible(web_browser_)) {
UnhideToolBand();
}
ClearCachedVisibility(web_browser_);
CloseNotificationWindow();
}
void ToolBandVisibility::UnhideToolBand() {
// Ignore ShowDW calls that are triggered by our calls here to
// ShowBrowserBar.
ceee_module_util::SetIgnoreShowDWChanges(true);
CComVariant toolband_class(CLSID_ToolBand);
CComVariant show(false);
CComVariant empty;
show = true;
web_browser_->ShowBrowserBar(&toolband_class, &show, &empty);
// Force IE to ignore bad caching. This is a problem generally before IE7,
// and at least sometimes even in IE7 (bb1291042).
show = false;
web_browser_->ShowBrowserBar(&toolband_class, &show, &empty);
show = true;
web_browser_->ShowBrowserBar(&toolband_class, &show, &empty);
ceee_module_util::SetIgnoreShowDWChanges(false);
}
|
