Enable keyboard accelerators while a menu is open

ui/views/controls/menu/menu_event_filter.cc

Index: ui/views/controls/menu/menu_event_filter.cc
diff --git a/ui/views/controls/menu/menu_event_filter.cc b/ui/views/controls/menu/menu_event_filter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e054fe1b35bd580ff4caafef8822d0882edbba3a
--- /dev/null
+++ b/ui/views/controls/menu/menu_event_filter.cc
@@ -0,0 +1,134 @@
+// Copyright 2015 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 "ui/views/controls/menu/menu_event_filter.h"
+
+#include "ui/aura/window.h"
+#include "ui/aura/window_property.h"
+#include "ui/base/accelerators/accelerator.h"
+#include "ui/events/keycodes/keyboard_code_conversion.h"
+#include "ui/views/controls/menu/menu_controller.h"
+
+DECLARE_WINDOW_PROPERTY_TYPE(views::MenuEventFilter::Delegate*);
+
+DEFINE_LOCAL_WINDOW_PROPERTY_KEY(views::MenuEventFilter::Delegate*,
+                                 kMenuEventFilterDelegateKey,
+                                 nullptr);
+
+namespace views {
+
+namespace {
+
+const int kKeyFlagsMask = ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN |
+                          ui::EF_ALT_DOWN | ui::EF_COMMAND_DOWN;
+
+// Defines a NULL-Object delegate for non-ash platforms.
+class DefaultMenuDelegate : public MenuEventFilter::Delegate {
+ public:
+  DefaultMenuDelegate() {}
+  ~DefaultMenuDelegate() override {}
+
+  // MenuEventFilter::Delegate:
+  void StoreInHistory(const ui::Accelerator& accelerator) override {}
+  bool ProcessAccelerator(const ui::Accelerator& accelerator,
+                          MenuEventFilter* owner) override {
+    return true;
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DefaultMenuDelegate);
+};
+
+}  // namespace
+
+MenuEventFilter::MenuEventFilter()
+    : default_delegate_(new DefaultMenuDelegate),
+      filter_delegate_(nullptr) {
+}
+
+MenuEventFilter::~MenuEventFilter() {
+}
+
+// static
+void MenuEventFilter::SetMenuEventFilterDelegate(
+    aura::Window* root_window,
+    MenuEventFilter::Delegate* delegate) {
+  DCHECK(root_window);
+  DCHECK(delegate);
+  DCHECK_EQ(root_window->GetRootWindow(), root_window);
+  root_window->SetProperty(kMenuEventFilterDelegateKey, delegate);
+}
+
+// static
+MenuEventFilter::Delegate* MenuEventFilter::GetMenuEventFilterDelegate(
+    aura::Window* root_window) {
+  DCHECK(root_window);
+  DCHECK_EQ(root_window->GetRootWindow(), root_window);
+  return root_window->GetProperty(kMenuEventFilterDelegateKey);
+}
+
+void MenuEventFilter::OnKeyEvent(ui::KeyEvent* event) {
+  DCHECK(event);
+
+  MenuEventFilter::Delegate* delegate =
+      filter_delegate_ ? filter_delegate_ : default_delegate_.get();
+  DCHECK(delegate);
+
+  // First record the current accelerator (this is normally done by the
+  // AcceleratorFilter, but since the MenuEventFilter will precede the
+  // AcceleratorFilter in the pre-target handlers list, we have to do it here).
+  ui::Accelerator accelerator(*event);
+  delegate->StoreInHistory(accelerator);
+
+  MenuController* menu_controller = MenuController::GetActiveInstance();
+  CHECK(menu_controller);
+
+  bool should_stop_propagation = true;
+  const int flags = event->flags();
+  if (event->type() != ui::ET_KEY_PRESSED || (flags & kKeyFlagsMask) != 0) {
+    should_stop_propagation =
+        delegate->ProcessAccelerator(accelerator, this);
+  } else {
+    if (menu_controller->OnKeyDown(event->key_code())) {
+      char c = ui::GetCharacterFromKeyCode(event->key_code(), flags);
+      if (!menu_controller->SelectByChar(c)) {
+        should_stop_propagation = delegate->ProcessAccelerator(accelerator,
+                                                               this);
+      }
+    }
+  }
+
+  if (menu_controller->exit_type() != MenuController::EXIT_NONE)
+    menu_controller->TerminateNestedMessageLoop();
+
+  if (should_stop_propagation)
+    event->StopPropagation();
+}
+
+void MenuEventFilter::OnTouchEvent(ui::TouchEvent* event) {
+  if (event->type() == ui::ET_TOUCH_RELEASED ||
+      event->type() == ui::ET_TOUCH_CANCELLED) {
+    // Don't allow the event copy to clear the native touch id
+    // mapping, or we'll lose the mapping before the initial event
+    // has finished being dispatched.
+    event->set_should_remove_native_touch_id_mapping(false);
+  }
+}
+
+void MenuEventFilter::SetDelegate(MenuEventFilter::Delegate* delegate) {
+  DCHECK(delegate);
+  filter_delegate_ = delegate;
+}
+
+void MenuEventFilter::ClearDelegate() {
+  filter_delegate_ = nullptr;
+}
+
+void MenuEventFilter::CloseMenu() const {
+  MenuController* menu_controller = MenuController::GetActiveInstance();
+  CHECK(menu_controller);
+  menu_controller->CancelAll();
+}
+
+}  // namespace views