Implement first part of supporting global extension commands.

chrome/browser/extensions/global_shortcut_listener.cc

Index: chrome/browser/extensions/global_shortcut_listener.cc
diff --git a/chrome/browser/extensions/global_shortcut_listener.cc b/chrome/browser/extensions/global_shortcut_listener.cc
new file mode 100644
index 0000000000000000000000000000000000000000..4ace06bce5a56b27dd7e4c760c9520496d432d21
--- /dev/null
+++ b/chrome/browser/extensions/global_shortcut_listener.cc
@@ -0,0 +1,56 @@
+// Copyright (c) 2013 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 "chrome/browser/extensions/global_shortcut_listener.h"
+#include "chrome/browser/profiles/profile.h"
+#include "ui/base/accelerators/accelerator.h"
+
+namespace extensions {
+
+GlobalShortcutListener::GlobalShortcutListener() {
+}
+
+GlobalShortcutListener::~GlobalShortcutListener() {
+  STLDeleteContainerPairSecondPointers(accelerator_map_.begin(),
+                                       accelerator_map_.end());
+}
+
+void GlobalShortcutListener::RegisterAccelerator(
+    const ui::Accelerator& accelerator, Observer* observer) {
+  AcceleratorMap::const_iterator it = accelerator_map_.find(accelerator);
+  if (it == accelerator_map_.end()) {
+    Observers* observers = new Observers;
+    observers->AddObserver(observer);
+    accelerator_map_[accelerator] = observers;
+  } else {
+    // Make sure we don't register the same accelerator twice.
+    DCHECK(!accelerator_map_[accelerator]->HasObserver(observer));
+    accelerator_map_[accelerator]->AddObserver(observer);
+  }

[zhchbin, 2013/09/20 07:49:23]

On linux I need to know which accelerator is registering or unregistering, so
that we can listen global hotkey via "XGrabKey". I think it's same on MAC, via
"RegisterEventHotKey".

AFAICS, On linux and mac we didn't have an easy way that can listen for all
keyboard event.

[Finnur, 2013/09/20 13:01:12]

I'm not sure I understand this comment. You have both the |accelerator| and
|observer| here. What am I missing?

On 2013/09/20 07:49:23, zhchbin wrote:

[zhchbin, 2013/09/21 02:07:50]

I mean to said that this function should add some logic that is implemented
platform specified. Something in my mind:

GlobalShortcutListener::RegisterAccelerator(
    const ui::Accelerator& accelerator, Observer* observer) {
  if (RegisterAcceleratorImpl(accelerator)) {
    ...  // Cross platform code.
  }
}

Then on windows:

GlobalShortcutListenerWin::RegisterAcceleratorImpl(
  const ui::Accelerator& accelerator) {
  // Register using "RegisterHotkey"
}

On Linux

GlobalShortcutListenerLinux::RegisterAcceleratorImpl(
  const ui::Accelerator& accelerator) {
  // Register using "XGrabKey"
}

On Mac

GlobalShortcutListenerCocoa::RegisterAcceleratorImpl(
  const ui::Accelerator& accelerator) {
  // Register using "RegisterEventHotKey"
}

Just the picture about how to implement it on different platforms.


On 2013/09/20 13:01:12, Finnur wrote:

[Finnur, 2013/09/21 12:23:50]

I see. I'll take a look on Monday.

On 2013/09/21 02:07:50, zhchbin wrote:

+}
+
+void GlobalShortcutListener::UnregisterAccelerator(
+    const ui::Accelerator& accelerator, Observer* observer) {
+  AcceleratorMap::const_iterator it = accelerator_map_.find(accelerator);
+  // Make sure we're unregistering something that has been registered.
+  DCHECK(it != accelerator_map_.end());
+  DCHECK(it->second->HasObserver(observer));
+  it->second->RemoveObserver(observer);
+  if (!it->second->might_have_observers())
+    accelerator_map_.erase(it);
+}
+
+bool GlobalShortcutListener::NotifyKeyPressed(
+    const ui::Accelerator& accelerator) {
+  AcceleratorMap::const_iterator it = accelerator_map_.find(accelerator);
+  if (it == accelerator_map_.end())
+    return false;  // No-one is listening to this key.
+  // The observer list should not be empty.
+  DCHECK(it->second->might_have_observers());
+
+  FOR_EACH_OBSERVER(Observer, *(it->second), OnKeyPressed(accelerator));
+  return true;
+}
+
+}  // namespace extensions