root/ui/views/controls/menu/menu_controller.cc

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DEFINITIONS

This source file includes following definitions.
  1. MatchesMnemonic
  2. TitleMatchesMnemonic
  3. GetOwnerRootWindow
  4. root_
  5. OnWindowActivated
  6. OnWindowDestroying
  7. OnCancelMode
  8. Cleanup
  9. GetFirstHotTrackedView
  10. GetFirstFocusableView
  11. GetInitialFocusableView
  12. GetNextFocusableView
  13. start_y_
  14. Update
  15. StopScrolling
  16. submenu
  17. Run
  18. context_menu
  19. GetActiveInstance
  20. Run
  21. Cancel
  22. OnMousePressed
  23. OnMouseDragged
  24. OnMouseReleased
  25. OnMouseMoved
  26. OnMouseEntered
  27. OnMouseWheel
  28. OnGestureEvent
  29. GetDropFormats
  30. AreDropTypesRequired
  31. CanDrop
  32. OnDragEntered
  33. OnDragUpdated
  34. OnDragExited
  35. OnPerformDrop
  36. OnDragEnteredScrollButton
  37. OnDragExitedScrollButton
  38. UpdateSubmenuSelection
  39. OnWidgetDestroying
  40. TurnOffMenuSelectionHoldForTest
  41. SetSelection
  42. SetSelectionOnPointerDown
  43. StartDrag
  44. OnKeyDown
  45. item_selected_by_touch_
  46. RunMessageLoop
  47. SendAcceleratorToHotTrackedView
  48. UpdateInitialLocation
  49. Accept
  50. ShowSiblingMenu
  51. ShowContextMenu
  52. CloseAllNestedMenus
  53. GetMenuItemAt
  54. GetEmptyMenuItemAt
  55. IsScrollButtonAt
  56. GetMenuPart
  57. GetMenuPartByScreenCoordinateUsingMenu
  58. GetMenuPartByScreenCoordinateImpl
  59. DoesSubmenuContainLocation
  60. CommitPendingSelection
  61. CloseMenu
  62. OpenMenu
  63. OpenMenuImpl
  64. MenuChildrenChanged
  65. BuildPathsAndCalculateDiff
  66. BuildMenuItemPath
  67. StartShowTimer
  68. StopShowTimer
  69. StartCancelAllTimer
  70. StopCancelAllTimer
  71. CalculateMenuBounds
  72. CalculateBubbleMenuBounds
  73. MenuDepth
  74. IncrementSelection
  75. FindNextSelectableMenuItem
  76. OpenSubmenuChangeSelectionIfCan
  77. CloseSubmenu
  78. FindChildForMnemonic
  79. AcceptOrSelect
  80. SelectByChar
  81. RepostEvent
  82. SetDropMenuItem
  83. UpdateScrolling
  84. StopScrolling
  85. UpdateActiveMouseView
  86. SendMouseReleaseToActiveView
  87. SendMouseCaptureLostToActiveView
  88. SetActiveMouseView
  89. GetActiveMouseView
  90. SetExitType
  91. ShouldQuitNow
  92. HandleMouseLocation
  93. GetScreen

// Copyright (c) 2012 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_controller.h"

#if defined(OS_WIN)
#include <windowsx.h>
#endif

#include "base/i18n/case_conversion.h"
#include "base/i18n/rtl.h"
#include "base/run_loop.h"
#include "base/strings/utf_string_conversions.h"
#include "base/time/time.h"
#include "ui/aura/env.h"
#include "ui/aura/window.h"
#include "ui/aura/window_event_dispatcher.h"
#include "ui/base/dragdrop/drag_utils.h"
#include "ui/base/dragdrop/os_exchange_data.h"
#include "ui/base/l10n/l10n_util.h"
#include "ui/events/event_constants.h"
#include "ui/events/event_utils.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/gfx/screen.h"
#include "ui/gfx/vector2d.h"
#include "ui/native_theme/native_theme.h"
#include "ui/views/controls/button/menu_button.h"
#include "ui/views/controls/menu/menu_config.h"
#include "ui/views/controls/menu/menu_controller_delegate.h"
#include "ui/views/controls/menu/menu_host_root_view.h"
#include "ui/views/controls/menu/menu_message_pump_dispatcher.h"
#include "ui/views/controls/menu/menu_scroll_view_container.h"
#include "ui/views/controls/menu/submenu_view.h"
#include "ui/views/drag_utils.h"
#include "ui/views/event_utils.h"
#include "ui/views/focus/view_storage.h"
#include "ui/views/mouse_constants.h"
#include "ui/views/view_constants.h"
#include "ui/views/views_delegate.h"
#include "ui/views/widget/root_view.h"
#include "ui/views/widget/tooltip_manager.h"
#include "ui/views/widget/widget.h"
#include "ui/wm/public/activation_change_observer.h"
#include "ui/wm/public/activation_client.h"
#include "ui/wm/public/dispatcher_client.h"
#include "ui/wm/public/drag_drop_client.h"

#if defined(OS_WIN)
#include "ui/base/win/internal_constants.h"
#include "ui/views/win/hwnd_util.h"
#endif

using base::Time;
using base::TimeDelta;
using ui::OSExchangeData;

// Period of the scroll timer (in milliseconds).
static const int kScrollTimerMS = 30;

// Amount of time from when the drop exits the menu and the menu is hidden.
static const int kCloseOnExitTime = 1200;

// If a context menu is invoked by touch, we shift the menu by this offset so
// that the finger does not obscure the menu.
static const int kCenteredContextMenuYOffset = -15;

namespace views {

namespace {

// When showing context menu on mouse down, the user might accidentally select
// the menu item on the subsequent mouse up. To prevent this, we add the
// following delay before the user is able to select an item.
static int menu_selection_hold_time_ms = kMinimumMsPressedToActivate;

// The spacing offset for the bubble tip.
const int kBubbleTipSizeLeftRight = 12;
const int kBubbleTipSizeTopBottom = 11;

// The maximum distance (in DIPS) that the mouse can be moved before it should
// trigger a mouse menu item activation (regardless of how long the menu has
// been showing).
const float kMaximumLengthMovedToActivate = 4.0f;

// Returns true if the mnemonic of |menu| matches key.
bool MatchesMnemonic(MenuItemView* menu, base::char16 key) {
  return key != 0 && menu->GetMnemonic() == key;
}

// Returns true if |menu| doesn't have a mnemonic and first character of the its
// title is |key|.
bool TitleMatchesMnemonic(MenuItemView* menu, base::char16 key) {
  if (menu->GetMnemonic())
    return false;

  base::string16 lower_title = base::i18n::ToLower(menu->title());
  return !lower_title.empty() && lower_title[0] == key;
}

aura::Window* GetOwnerRootWindow(views::Widget* owner) {
  return owner ? owner->GetNativeWindow()->GetRootWindow() : NULL;
}

// ActivationChangeObserverImpl is used to observe activation changes and close
// the menu. Additionally it listens for the root window to be destroyed and
// cancel the menu as well.
class ActivationChangeObserverImpl
    : public aura::client::ActivationChangeObserver,
      public aura::WindowObserver,
      public ui::EventHandler {
 public:
  ActivationChangeObserverImpl(MenuController* controller, aura::Window* root)
      : controller_(controller),
        root_(root) {
    aura::client::GetActivationClient(root_)->AddObserver(this);
    root_->AddObserver(this);
    root_->AddPreTargetHandler(this);
  }

  virtual ~ActivationChangeObserverImpl() {
    Cleanup();
  }

  // aura::client::ActivationChangeObserver:
  virtual void OnWindowActivated(aura::Window* gained_active,
                                 aura::Window* lost_active) OVERRIDE {
    if (!controller_->drag_in_progress())
      controller_->CancelAll();
  }

  // aura::WindowObserver:
  virtual void OnWindowDestroying(aura::Window* window) OVERRIDE {
    Cleanup();
  }

  // ui::EventHandler:
  virtual void OnCancelMode(ui::CancelModeEvent* event) OVERRIDE {
    controller_->CancelAll();
  }

 private:
  void Cleanup() {
    if (!root_)
      return;
    // The ActivationClient may have been destroyed by the time we get here.
    aura::client::ActivationClient* client =
        aura::client::GetActivationClient(root_);
    if (client)
      client->RemoveObserver(this);
    root_->RemovePreTargetHandler(this);
    root_->RemoveObserver(this);
    root_ = NULL;
  }

  MenuController* controller_;
  aura::Window* root_;

  DISALLOW_COPY_AND_ASSIGN(ActivationChangeObserverImpl);
};

}  // namespace

// Returns the first descendant of |view| that is hot tracked.
static CustomButton* GetFirstHotTrackedView(View* view) {
  if (!view)
    return NULL;
  CustomButton* button = CustomButton::AsCustomButton(view);
  if (button) {
    if (button->IsHotTracked())
      return button;
  }

  for (int i = 0; i < view->child_count(); ++i) {
    CustomButton* hot_view = GetFirstHotTrackedView(view->child_at(i));
    if (hot_view)
      return hot_view;
  }
  return NULL;
}

// Recurses through the child views of |view| returning the first view starting
// at |start| that is focusable. A value of -1 for |start| indicates to start at
// the first view (if |forward| is false, iterating starts at the last view). If
// |forward| is true the children are considered first to last, otherwise last
// to first.
static View* GetFirstFocusableView(View* view, int start, bool forward) {
  if (forward) {
    for (int i = start == -1 ? 0 : start; i < view->child_count(); ++i) {
      View* deepest = GetFirstFocusableView(view->child_at(i), -1, forward);
      if (deepest)
        return deepest;
    }
  } else {
    for (int i = start == -1 ? view->child_count() - 1 : start; i >= 0; --i) {
      View* deepest = GetFirstFocusableView(view->child_at(i), -1, forward);
      if (deepest)
        return deepest;
    }
  }
  return view->IsFocusable() ? view : NULL;
}

// Returns the first child of |start| that is focusable.
static View* GetInitialFocusableView(View* start, bool forward) {
  return GetFirstFocusableView(start, -1, forward);
}

// Returns the next view after |start_at| that is focusable. Returns NULL if
// there are no focusable children of |ancestor| after |start_at|.
static View* GetNextFocusableView(View* ancestor,
                                  View* start_at,
                                  bool forward) {
  DCHECK(ancestor->Contains(start_at));
  View* parent = start_at;
  do {
    View* new_parent = parent->parent();
    int index = new_parent->GetIndexOf(parent);
    index += forward ? 1 : -1;
    if (forward || index != -1) {
      View* next = GetFirstFocusableView(new_parent, index, forward);
      if (next)
        return next;
    }
    parent = new_parent;
  } while (parent != ancestor);
  return NULL;
}

// MenuScrollTask --------------------------------------------------------------

// MenuScrollTask is used when the SubmenuView does not all fit on screen and
// the mouse is over the scroll up/down buttons. MenuScrollTask schedules
// itself with a RepeatingTimer. When Run is invoked MenuScrollTask scrolls
// appropriately.

class MenuController::MenuScrollTask {
 public:
  MenuScrollTask() : submenu_(NULL), is_scrolling_up_(false), start_y_(0) {
    pixels_per_second_ = MenuItemView::pref_menu_height() * 20;
  }

  void Update(const MenuController::MenuPart& part) {
    if (!part.is_scroll()) {
      StopScrolling();
      return;
    }
    DCHECK(part.submenu);
    SubmenuView* new_menu = part.submenu;
    bool new_is_up = (part.type == MenuController::MenuPart::SCROLL_UP);
    if (new_menu == submenu_ && is_scrolling_up_ == new_is_up)
      return;

    start_scroll_time_ = base::Time::Now();
    start_y_ = part.submenu->GetVisibleBounds().y();
    submenu_ = new_menu;
    is_scrolling_up_ = new_is_up;

    if (!scrolling_timer_.IsRunning()) {
      scrolling_timer_.Start(FROM_HERE,
                             TimeDelta::FromMilliseconds(kScrollTimerMS),
                             this, &MenuScrollTask::Run);
    }
  }

  void StopScrolling() {
    if (scrolling_timer_.IsRunning()) {
      scrolling_timer_.Stop();
      submenu_ = NULL;
    }
  }

  // The menu being scrolled. Returns null if not scrolling.
  SubmenuView* submenu() const { return submenu_; }

 private:
  void Run() {
    DCHECK(submenu_);
    gfx::Rect vis_rect = submenu_->GetVisibleBounds();
    const int delta_y = static_cast<int>(
        (base::Time::Now() - start_scroll_time_).InMilliseconds() *
        pixels_per_second_ / 1000);
    vis_rect.set_y(is_scrolling_up_ ?
        std::max(0, start_y_ - delta_y) :
        std::min(submenu_->height() - vis_rect.height(), start_y_ + delta_y));
    submenu_->ScrollRectToVisible(vis_rect);
  }

  // SubmenuView being scrolled.
  SubmenuView* submenu_;

  // Direction scrolling.
  bool is_scrolling_up_;

  // Timer to periodically scroll.
  base::RepeatingTimer<MenuScrollTask> scrolling_timer_;

  // Time we started scrolling at.
  base::Time start_scroll_time_;

  // How many pixels to scroll per second.
  int pixels_per_second_;

  // Y-coordinate of submenu_view_ when scrolling started.
  int start_y_;

  DISALLOW_COPY_AND_ASSIGN(MenuScrollTask);
};

// MenuController:SelectByCharDetails ----------------------------------------

struct MenuController::SelectByCharDetails {
  SelectByCharDetails()
      : first_match(-1),
        has_multiple(false),
        index_of_item(-1),
        next_match(-1) {
  }

  // Index of the first menu with the specified mnemonic.
  int first_match;

  // If true there are multiple menu items with the same mnemonic.
  bool has_multiple;

  // Index of the selected item; may remain -1.
  int index_of_item;

  // If there are multiple matches this is the index of the item after the
  // currently selected item whose mnemonic matches. This may remain -1 even
  // though there are matches.
  int next_match;
};

// MenuController:State ------------------------------------------------------

MenuController::State::State()
    : item(NULL),
      submenu_open(false),
      anchor(MenuItemView::TOPLEFT),
      context_menu(false) {}

MenuController::State::~State() {}

// MenuController ------------------------------------------------------------

// static
MenuController* MenuController::active_instance_ = NULL;

// static
MenuController* MenuController::GetActiveInstance() {
  return active_instance_;
}

MenuItemView* MenuController::Run(Widget* parent,
                                  MenuButton* button,
                                  MenuItemView* root,
                                  const gfx::Rect& bounds,
                                  MenuItemView::AnchorPosition position,
                                  bool context_menu,
                                  int* result_event_flags) {
  exit_type_ = EXIT_NONE;
  possible_drag_ = false;
  drag_in_progress_ = false;
  closing_event_time_ = base::TimeDelta();
  menu_start_time_ = base::TimeTicks::Now();
  menu_start_mouse_press_loc_ = gfx::Point();

  // If we are shown on mouse press, we will eat the subsequent mouse down and
  // the parent widget will not be able to reset its state (it might have mouse
  // capture from the mouse down). So we clear its state here.
  if (parent) {
    View* root_view = parent->GetRootView();
    if (root_view) {
      root_view->SetMouseHandler(NULL);
      const ui::Event* event =
          static_cast<internal::RootView*>(root_view)->current_event();
      if (event && event->type() == ui::ET_MOUSE_PRESSED) {
        gfx::Point screen_loc(
            static_cast<const ui::MouseEvent*>(event)->location());
        View::ConvertPointToScreen(
            static_cast<View*>(event->target()), &screen_loc);
        menu_start_mouse_press_loc_ = screen_loc;
      }
    }
  }

  bool nested_menu = showing_;
  if (showing_) {
    // Only support nesting of blocking_run menus, nesting of
    // blocking/non-blocking shouldn't be needed.
    DCHECK(blocking_run_);

    // We're already showing, push the current state.
    menu_stack_.push_back(state_);

    // The context menu should be owned by the same parent.
    DCHECK_EQ(owner_, parent);
  } else {
    showing_ = true;
  }

  // Reset current state.
  pending_state_ = State();
  state_ = State();
  UpdateInitialLocation(bounds, position, context_menu);

  if (owner_)
    owner_->RemoveObserver(this);
  owner_ = parent;
  if (owner_)
    owner_->AddObserver(this);

  // Set the selection, which opens the initial menu.
  SetSelection(root, SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);

  if (!blocking_run_) {
    // Start the timer to hide the menu. This is needed as we get no
    // notification when the drag has finished.
    StartCancelAllTimer();
    return NULL;
  }

  if (button)
    menu_button_ = button;

  // Make sure Chrome doesn't attempt to shut down while the menu is showing.
  if (ViewsDelegate::views_delegate)
    ViewsDelegate::views_delegate->AddRef();

  // We need to turn on nestable tasks as in some situations (pressing alt-f for
  // one) the menus are run from a task. If we don't do this and are invoked
  // from a task none of the tasks we schedule are processed and the menu
  // appears totally broken.
  message_loop_depth_++;
  DCHECK_LE(message_loop_depth_, 2);
  RunMessageLoop(nested_menu);
  message_loop_depth_--;

  if (ViewsDelegate::views_delegate)
    ViewsDelegate::views_delegate->ReleaseRef();

  // Close any open menus.
  SetSelection(NULL, SELECTION_UPDATE_IMMEDIATELY | SELECTION_EXIT);

#if defined(OS_WIN)
  // On Windows, if we select the menu item by touch and if the window at the
  // location is another window on the same thread, that window gets a
  // WM_MOUSEACTIVATE message and ends up activating itself, which is not
  // correct. We workaround this by setting a property on the window at the
  // current cursor location. We check for this property in our
  // WM_MOUSEACTIVATE handler and don't activate the window if the property is
  // set.
  if (item_selected_by_touch_) {
    item_selected_by_touch_ = false;
    POINT cursor_pos;
    ::GetCursorPos(&cursor_pos);
     HWND window = ::WindowFromPoint(cursor_pos);
     if (::GetWindowThreadProcessId(window, NULL) ==
                                    ::GetCurrentThreadId()) {
       ::SetProp(window, ui::kIgnoreTouchMouseActivateForWindow,
                 reinterpret_cast<HANDLE>(true));
     }
  }
#endif

  if (nested_menu) {
    DCHECK(!menu_stack_.empty());
    // We're running from within a menu, restore the previous state.
    // The menus are already showing, so we don't have to show them.
    state_ = menu_stack_.back();
    pending_state_ = menu_stack_.back();
    menu_stack_.pop_back();
  } else {
    showing_ = false;
    did_capture_ = false;
  }

  MenuItemView* result = result_;
  // In case we're nested, reset result_.
  result_ = NULL;

  if (result_event_flags)
    *result_event_flags = accept_event_flags_;

  if (exit_type_ == EXIT_OUTERMOST) {
    SetExitType(EXIT_NONE);
  } else {
    if (nested_menu && result) {
      // We're nested and about to return a value. The caller might enter
      // another blocking loop. We need to make sure all menus are hidden
      // before that happens otherwise the menus will stay on screen.
      CloseAllNestedMenus();
      SetSelection(NULL, SELECTION_UPDATE_IMMEDIATELY | SELECTION_EXIT);

      // Set exit_all_, which makes sure all nested loops exit immediately.
      if (exit_type_ != EXIT_DESTROYED)
        SetExitType(EXIT_ALL);
    }
  }

  // If we stopped running because one of the menus was destroyed chances are
  // the button was also destroyed.
  if (exit_type_ != EXIT_DESTROYED && menu_button_) {
    menu_button_->SetState(CustomButton::STATE_NORMAL);
    menu_button_->SchedulePaint();
  }
  return result;
}

void MenuController::Cancel(ExitType type) {
  // If the menu has already been destroyed, no further cancellation is
  // needed.  We especially don't want to set the |exit_type_| to a lesser
  // value.
  if (exit_type_ == EXIT_DESTROYED || exit_type_ == type)
    return;

  if (!showing_) {
    // This occurs if we're in the process of notifying the delegate for a drop
    // and the delegate cancels us.
    return;
  }

  MenuItemView* selected = state_.item;
  SetExitType(type);

  SendMouseCaptureLostToActiveView();

  // Hide windows immediately.
  SetSelection(NULL, SELECTION_UPDATE_IMMEDIATELY | SELECTION_EXIT);

  if (!blocking_run_) {
    // If we didn't block the caller we need to notify the menu, which
    // triggers deleting us.
    DCHECK(selected);
    showing_ = false;
    delegate_->DropMenuClosed(
        internal::MenuControllerDelegate::NOTIFY_DELEGATE,
        selected->GetRootMenuItem());
    // WARNING: the call to MenuClosed deletes us.
    return;
  }
}

void MenuController::OnMousePressed(SubmenuView* source,
                                    const ui::MouseEvent& event) {
  SetSelectionOnPointerDown(source, event);
}

void MenuController::OnMouseDragged(SubmenuView* source,
                                    const ui::MouseEvent& event) {
  MenuPart part = GetMenuPart(source, event.location());
  UpdateScrolling(part);

  if (!blocking_run_)
    return;

  if (possible_drag_) {
    if (View::ExceededDragThreshold(event.location() - press_pt_))
      StartDrag(source, press_pt_);
    return;
  }
  MenuItemView* mouse_menu = NULL;
  if (part.type == MenuPart::MENU_ITEM) {
    if (!part.menu)
      part.menu = source->GetMenuItem();
    else
      mouse_menu = part.menu;
    SetSelection(part.menu ? part.menu : state_.item, SELECTION_OPEN_SUBMENU);
  } else if (part.type == MenuPart::NONE) {
    ShowSiblingMenu(source, event.location());
  }
  UpdateActiveMouseView(source, event, mouse_menu);
}

void MenuController::OnMouseReleased(SubmenuView* source,
                                     const ui::MouseEvent& event) {
  if (!blocking_run_)
    return;

  DCHECK(state_.item);
  possible_drag_ = false;
  DCHECK(blocking_run_);
  MenuPart part = GetMenuPart(source, event.location());
  if (event.IsRightMouseButton() && part.type == MenuPart::MENU_ITEM) {
    MenuItemView* menu = part.menu;
    // |menu| is NULL means this event is from an empty menu or a separator.
    // If it is from an empty menu, use parent context menu instead of that.
    if (menu == NULL &&
        part.submenu->child_count() == 1 &&
        part.submenu->child_at(0)->id() == MenuItemView::kEmptyMenuItemViewID) {
      menu = part.parent;
    }

    if (menu != NULL && ShowContextMenu(menu, source, event,
                                        ui::MENU_SOURCE_MOUSE))
      return;
  }

  // We can use Ctrl+click or the middle mouse button to recursively open urls
  // for selected folder menu items. If it's only a left click, show the
  // contents of the folder.
  if (!part.is_scroll() && part.menu &&
      !(part.menu->HasSubmenu() &&
        (event.flags() & ui::EF_LEFT_MOUSE_BUTTON))) {
    if (GetActiveMouseView()) {
      SendMouseReleaseToActiveView(source, event);
      return;
    }
    // If a mouse release was received quickly after showing.
    base::TimeDelta time_shown = base::TimeTicks::Now() - menu_start_time_;
    if (time_shown.InMilliseconds() < menu_selection_hold_time_ms) {
      // And it wasn't far from the mouse press location.
      gfx::Point screen_loc(event.location());
      View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);
      gfx::Vector2d moved = screen_loc - menu_start_mouse_press_loc_;
      if (moved.Length() < kMaximumLengthMovedToActivate) {
        // Ignore the mouse release as it was likely this menu was shown under
        // the mouse and the action was just a normal click.
        return;
      }
    }
    if (part.menu->GetDelegate()->ShouldExecuteCommandWithoutClosingMenu(
            part.menu->GetCommand(), event)) {
      part.menu->GetDelegate()->ExecuteCommand(part.menu->GetCommand(),
                                               event.flags());
      return;
    }
    if (!part.menu->NonIconChildViewsCount() &&
        part.menu->GetDelegate()->IsTriggerableEvent(part.menu, event)) {
      base::TimeDelta shown_time = base::TimeTicks::Now() - menu_start_time_;
      if (!state_.context_menu || !View::ShouldShowContextMenuOnMousePress() ||
          shown_time.InMilliseconds() > menu_selection_hold_time_ms) {
        Accept(part.menu, event.flags());
      }
      return;
    }
  } else if (part.type == MenuPart::MENU_ITEM) {
    // User either clicked on empty space, or a menu that has children.
    SetSelection(part.menu ? part.menu : state_.item,
                 SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
  }
  SendMouseCaptureLostToActiveView();
}

void MenuController::OnMouseMoved(SubmenuView* source,
                                  const ui::MouseEvent& event) {
  HandleMouseLocation(source, event.location());
}

void MenuController::OnMouseEntered(SubmenuView* source,
                                    const ui::MouseEvent& event) {
  // MouseEntered is always followed by a mouse moved, so don't need to
  // do anything here.
}

bool MenuController::OnMouseWheel(SubmenuView* source,
                                  const ui::MouseWheelEvent& event) {
  MenuPart part = GetMenuPart(source, event.location());
  return part.submenu && part.submenu->OnMouseWheel(event);
}

void MenuController::OnGestureEvent(SubmenuView* source,
                                    ui::GestureEvent* event) {
  MenuPart part = GetMenuPart(source, event->location());
  if (event->type() == ui::ET_GESTURE_TAP_DOWN) {
    SetSelectionOnPointerDown(source, *event);
    event->StopPropagation();
  } else if (event->type() == ui::ET_GESTURE_LONG_PRESS) {
    if (part.type == MenuPart::MENU_ITEM && part.menu) {
      if (ShowContextMenu(part.menu, source, *event, ui::MENU_SOURCE_TOUCH))
        event->StopPropagation();
    }
  } else if (event->type() == ui::ET_GESTURE_TAP) {
    if (!part.is_scroll() && part.menu &&
        !(part.menu->HasSubmenu())) {
      if (part.menu->GetDelegate()->IsTriggerableEvent(
          part.menu, *event)) {
        Accept(part.menu, event->flags());
        item_selected_by_touch_ = true;
      }
      event->StopPropagation();
    } else if (part.type == MenuPart::MENU_ITEM) {
      // User either tapped on empty space, or a menu that has children.
      SetSelection(part.menu ? part.menu : state_.item,
                   SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
      event->StopPropagation();
    }
  } else if (event->type() == ui::ET_GESTURE_TAP_CANCEL &&
             part.menu &&
             part.type == MenuPart::MENU_ITEM) {
    // Move the selection to the parent menu so that the selection in the
    // current menu is unset. Make sure the submenu remains open by sending the
    // appropriate SetSelectionTypes flags.
    SetSelection(part.menu->GetParentMenuItem(),
        SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
    event->StopPropagation();
  }

  if (event->stopped_propagation())
      return;

  if (!part.submenu)
    return;
  part.submenu->OnGestureEvent(event);
}

bool MenuController::GetDropFormats(
      SubmenuView* source,
      int* formats,
      std::set<OSExchangeData::CustomFormat>* custom_formats) {
  return source->GetMenuItem()->GetDelegate()->GetDropFormats(
      source->GetMenuItem(), formats, custom_formats);
}

bool MenuController::AreDropTypesRequired(SubmenuView* source) {
  return source->GetMenuItem()->GetDelegate()->AreDropTypesRequired(
      source->GetMenuItem());
}

bool MenuController::CanDrop(SubmenuView* source, const OSExchangeData& data) {
  return source->GetMenuItem()->GetDelegate()->CanDrop(source->GetMenuItem(),
                                                       data);
}

void MenuController::OnDragEntered(SubmenuView* source,
                                   const ui::DropTargetEvent& event) {
  valid_drop_coordinates_ = false;
}

int MenuController::OnDragUpdated(SubmenuView* source,
                                  const ui::DropTargetEvent& event) {
  StopCancelAllTimer();

  gfx::Point screen_loc(event.location());
  View::ConvertPointToScreen(source, &screen_loc);
  if (valid_drop_coordinates_ && screen_loc == drop_pt_)
    return last_drop_operation_;
  drop_pt_ = screen_loc;
  valid_drop_coordinates_ = true;

  MenuItemView* menu_item = GetMenuItemAt(source, event.x(), event.y());
  bool over_empty_menu = false;
  if (!menu_item) {
    // See if we're over an empty menu.
    menu_item = GetEmptyMenuItemAt(source, event.x(), event.y());
    if (menu_item)
      over_empty_menu = true;
  }
  MenuDelegate::DropPosition drop_position = MenuDelegate::DROP_NONE;
  int drop_operation = ui::DragDropTypes::DRAG_NONE;
  if (menu_item) {
    gfx::Point menu_item_loc(event.location());
    View::ConvertPointToTarget(source, menu_item, &menu_item_loc);
    MenuItemView* query_menu_item;
    if (!over_empty_menu) {
      int menu_item_height = menu_item->height();
      if (menu_item->HasSubmenu() &&
          (menu_item_loc.y() > kDropBetweenPixels &&
           menu_item_loc.y() < (menu_item_height - kDropBetweenPixels))) {
        drop_position = MenuDelegate::DROP_ON;
      } else {
        drop_position = (menu_item_loc.y() < menu_item_height / 2) ?
            MenuDelegate::DROP_BEFORE : MenuDelegate::DROP_AFTER;
      }
      query_menu_item = menu_item;
    } else {
      query_menu_item = menu_item->GetParentMenuItem();
      drop_position = MenuDelegate::DROP_ON;
    }
    drop_operation = menu_item->GetDelegate()->GetDropOperation(
        query_menu_item, event, &drop_position);

    // If the menu has a submenu, schedule the submenu to open.
    SetSelection(menu_item, menu_item->HasSubmenu() ? SELECTION_OPEN_SUBMENU :
                 SELECTION_DEFAULT);

    if (drop_position == MenuDelegate::DROP_NONE ||
        drop_operation == ui::DragDropTypes::DRAG_NONE)
      menu_item = NULL;
  } else {
    SetSelection(source->GetMenuItem(), SELECTION_OPEN_SUBMENU);
  }
  SetDropMenuItem(menu_item, drop_position);
  last_drop_operation_ = drop_operation;
  return drop_operation;
}

void MenuController::OnDragExited(SubmenuView* source) {
  StartCancelAllTimer();

  if (drop_target_) {
    StopShowTimer();
    SetDropMenuItem(NULL, MenuDelegate::DROP_NONE);
  }
}

int MenuController::OnPerformDrop(SubmenuView* source,
                                  const ui::DropTargetEvent& event) {
  DCHECK(drop_target_);
  // NOTE: the delegate may delete us after invoking OnPerformDrop, as such
  // we don't call cancel here.

  MenuItemView* item = state_.item;
  DCHECK(item);

  MenuItemView* drop_target = drop_target_;
  MenuDelegate::DropPosition drop_position = drop_position_;

  // Close all menus, including any nested menus.
  SetSelection(NULL, SELECTION_UPDATE_IMMEDIATELY | SELECTION_EXIT);
  CloseAllNestedMenus();

  // Set state such that we exit.
  showing_ = false;
  SetExitType(EXIT_ALL);

  // If over an empty menu item, drop occurs on the parent.
  if (drop_target->id() == MenuItemView::kEmptyMenuItemViewID)
    drop_target = drop_target->GetParentMenuItem();

  if (!IsBlockingRun()) {
    delegate_->DropMenuClosed(
        internal::MenuControllerDelegate::DONT_NOTIFY_DELEGATE,
        item->GetRootMenuItem());
  }

  // WARNING: the call to MenuClosed deletes us.

  return drop_target->GetDelegate()->OnPerformDrop(
      drop_target, drop_position, event);
}

void MenuController::OnDragEnteredScrollButton(SubmenuView* source,
                                               bool is_up) {
  MenuPart part;
  part.type = is_up ? MenuPart::SCROLL_UP : MenuPart::SCROLL_DOWN;
  part.submenu = source;
  UpdateScrolling(part);

  // Do this to force the selection to hide.
  SetDropMenuItem(source->GetMenuItemAt(0), MenuDelegate::DROP_NONE);

  StopCancelAllTimer();
}

void MenuController::OnDragExitedScrollButton(SubmenuView* source) {
  StartCancelAllTimer();
  SetDropMenuItem(NULL, MenuDelegate::DROP_NONE);
  StopScrolling();
}

void MenuController::UpdateSubmenuSelection(SubmenuView* submenu) {
  if (submenu->IsShowing()) {
    gfx::Point point = GetScreen()->GetCursorScreenPoint();
    const SubmenuView* root_submenu =
        submenu->GetMenuItem()->GetRootMenuItem()->GetSubmenu();
    View::ConvertPointFromScreen(
        root_submenu->GetWidget()->GetRootView(), &point);
    HandleMouseLocation(submenu, point);
  }
}

void MenuController::OnWidgetDestroying(Widget* widget) {
  DCHECK_EQ(owner_, widget);
  owner_->RemoveObserver(this);
  owner_ = NULL;
}

// static
void MenuController::TurnOffMenuSelectionHoldForTest() {
  menu_selection_hold_time_ms = -1;
}

void MenuController::SetSelection(MenuItemView* menu_item,
                                  int selection_types) {
  size_t paths_differ_at = 0;
  std::vector<MenuItemView*> current_path;
  std::vector<MenuItemView*> new_path;
  BuildPathsAndCalculateDiff(pending_state_.item, menu_item, &current_path,
                             &new_path, &paths_differ_at);

  size_t current_size = current_path.size();
  size_t new_size = new_path.size();

  bool pending_item_changed = pending_state_.item != menu_item;
  if (pending_item_changed && pending_state_.item) {
    CustomButton* button = GetFirstHotTrackedView(pending_state_.item);
    if (button)
      button->SetHotTracked(false);
  }

  // Notify the old path it isn't selected.
  MenuDelegate* current_delegate =
      current_path.empty() ? NULL : current_path.front()->GetDelegate();
  for (size_t i = paths_differ_at; i < current_size; ++i) {
    if (current_delegate &&
        current_path[i]->GetType() == MenuItemView::SUBMENU) {
      current_delegate->WillHideMenu(current_path[i]);
    }
    current_path[i]->SetSelected(false);
  }

  // Notify the new path it is selected.
  for (size_t i = paths_differ_at; i < new_size; ++i) {
    new_path[i]->ScrollRectToVisible(new_path[i]->GetLocalBounds());
    new_path[i]->SetSelected(true);
  }

  if (menu_item && menu_item->GetDelegate())
    menu_item->GetDelegate()->SelectionChanged(menu_item);

  DCHECK(menu_item || (selection_types & SELECTION_EXIT) != 0);

  pending_state_.item = menu_item;
  pending_state_.submenu_open = (selection_types & SELECTION_OPEN_SUBMENU) != 0;

  // Stop timers.
  StopCancelAllTimer();
  // Resets show timer only when pending menu item is changed.
  if (pending_item_changed)
    StopShowTimer();

  if (selection_types & SELECTION_UPDATE_IMMEDIATELY)
    CommitPendingSelection();
  else if (pending_item_changed)
    StartShowTimer();

  // Notify an accessibility focus event on all menu items except for the root.
  if (menu_item &&
      (MenuDepth(menu_item) != 1 ||
       menu_item->GetType() != MenuItemView::SUBMENU)) {
    menu_item->NotifyAccessibilityEvent(
        ui::AX_EVENT_FOCUS, true);
  }
}

void MenuController::SetSelectionOnPointerDown(SubmenuView* source,
                                               const ui::LocatedEvent& event) {
  if (!blocking_run_)
    return;

  DCHECK(!GetActiveMouseView());

  MenuPart part = GetMenuPart(source, event.location());
  if (part.is_scroll())
    return;  // Ignore presses on scroll buttons.

  // When this menu is opened through a touch event, a simulated right-click
  // is sent before the menu appears.  Ignore it.
  if ((event.flags() & ui::EF_RIGHT_MOUSE_BUTTON) &&
      (event.flags() & ui::EF_FROM_TOUCH))
    return;

  if (part.type == MenuPart::NONE ||
      (part.type == MenuPart::MENU_ITEM && part.menu &&
       part.menu->GetRootMenuItem() != state_.item->GetRootMenuItem())) {
    // Remember the time when we repost the event. The owner can then use this
    // to figure out if this menu was finished with the same click which is
    // sent to it thereafter. Note that the time stamp front he event cannot be
    // used since the reposting will set a new timestamp when the event gets
    // processed. As such it is better to take the current time which will be
    // closer to the time when it arrives again in the menu handler.
    closing_event_time_ = ui::EventTimeForNow();

    // Mouse wasn't pressed over any menu, or the active menu, cancel.

#if defined(OS_WIN)
    // We're going to close and we own the mouse capture. We need to repost the
    // mouse down, otherwise the window the user clicked on won't get the event.
    if (!state_.item) {
      // We some times get an event after closing all the menus. Ignore it. Make
      // sure the menu is in fact not visible. If the menu is visible, then
      // we're in a bad state where we think the menu isn't visibile but it is.
      DCHECK(!source->GetWidget()->IsVisible());
    } else {
      RepostEvent(source, event);
    }
#endif

    // And close.
    ExitType exit_type = EXIT_ALL;
    if (!menu_stack_.empty()) {
      // We're running nested menus. Only exit all if the mouse wasn't over one
      // of the menus from the last run.
      gfx::Point screen_loc(event.location());
      View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);
      MenuPart last_part = GetMenuPartByScreenCoordinateUsingMenu(
          menu_stack_.back().item, screen_loc);
      if (last_part.type != MenuPart::NONE)
        exit_type = EXIT_OUTERMOST;
    }
    Cancel(exit_type);

#if defined(OS_CHROMEOS)
    // We're going to exit the menu and want to repost the event so that is
    // is handled normally after the context menu has exited. We call
    // RepostEvent after Cancel so that mouse capture has been released so
    // that finding the event target is unaffected by the current capture.
    RepostEvent(source, event);
#endif
    // Do not repost events for Linux Aura because this behavior is more
    // consistent with the behavior of other Linux apps.
    return;
  }

  // On a press we immediately commit the selection, that way a submenu
  // pops up immediately rather than after a delay.
  int selection_types = SELECTION_UPDATE_IMMEDIATELY;
  if (!part.menu) {
    part.menu = part.parent;
    selection_types |= SELECTION_OPEN_SUBMENU;
  } else {
    if (part.menu->GetDelegate()->CanDrag(part.menu)) {
      possible_drag_ = true;
      press_pt_ = event.location();
    }
    if (part.menu->HasSubmenu())
      selection_types |= SELECTION_OPEN_SUBMENU;
  }
  SetSelection(part.menu, selection_types);
}

void MenuController::StartDrag(SubmenuView* source,
                               const gfx::Point& location) {
  MenuItemView* item = state_.item;
  DCHECK(item);
  // Points are in the coordinates of the submenu, need to map to that of
  // the selected item. Additionally source may not be the parent of
  // the selected item, so need to map to screen first then to item.
  gfx::Point press_loc(location);
  View::ConvertPointToScreen(source->GetScrollViewContainer(), &press_loc);
  View::ConvertPointFromScreen(item, &press_loc);
  gfx::Point widget_loc(press_loc);
  View::ConvertPointToWidget(item, &widget_loc);
  scoped_ptr<gfx::Canvas> canvas(GetCanvasForDragImage(
      source->GetWidget(), gfx::Size(item->width(), item->height())));
  item->PaintButton(canvas.get(), MenuItemView::PB_FOR_DRAG);

  OSExchangeData data;
  item->GetDelegate()->WriteDragData(item, &data);
  drag_utils::SetDragImageOnDataObject(*canvas, item->size(),
                                       press_loc.OffsetFromOrigin(),
                                       &data);
  StopScrolling();
  int drag_ops = item->GetDelegate()->GetDragOperations(item);
  drag_in_progress_ = true;
  // TODO(varunjain): Properly determine and send DRAG_EVENT_SOURCE below.
  item->GetWidget()->RunShellDrag(NULL, data, widget_loc, drag_ops,
      ui::DragDropTypes::DRAG_EVENT_SOURCE_MOUSE);
  drag_in_progress_ = false;

  if (GetActiveInstance() == this) {
    if (showing_) {
      // We're still showing, close all menus.
      CloseAllNestedMenus();
      Cancel(EXIT_ALL);
    }  // else case, drop was on us.
  }  // else case, someone canceled us, don't do anything
}

bool MenuController::OnKeyDown(ui::KeyboardCode key_code) {
  DCHECK(blocking_run_);

  switch (key_code) {
    case ui::VKEY_UP:
      IncrementSelection(-1);
      break;

    case ui::VKEY_DOWN:
      IncrementSelection(1);
      break;

    // Handling of VK_RIGHT and VK_LEFT is different depending on the UI
    // layout.
    case ui::VKEY_RIGHT:
      if (base::i18n::IsRTL())
        CloseSubmenu();
      else
        OpenSubmenuChangeSelectionIfCan();
      break;

    case ui::VKEY_LEFT:
      if (base::i18n::IsRTL())
        OpenSubmenuChangeSelectionIfCan();
      else
        CloseSubmenu();
      break;

    case ui::VKEY_SPACE:
      if (SendAcceleratorToHotTrackedView() == ACCELERATOR_PROCESSED_EXIT)
        return false;
      break;

    case ui::VKEY_F4:
      if (!is_combobox_)
        break;
      // Fallthrough to accept on F4, so combobox menus match Windows behavior.
    case ui::VKEY_RETURN:
      if (pending_state_.item) {
        if (pending_state_.item->HasSubmenu()) {
          OpenSubmenuChangeSelectionIfCan();
        } else {
          SendAcceleratorResultType result = SendAcceleratorToHotTrackedView();
          if (result == ACCELERATOR_NOT_PROCESSED &&
              pending_state_.item->enabled()) {
            Accept(pending_state_.item, 0);
            return false;
          } else if (result == ACCELERATOR_PROCESSED_EXIT) {
            return false;
          }
        }
      }
      break;

    case ui::VKEY_ESCAPE:
      if (!state_.item->GetParentMenuItem() ||
          (!state_.item->GetParentMenuItem()->GetParentMenuItem() &&
           (!state_.item->HasSubmenu() ||
            !state_.item->GetSubmenu()->IsShowing()))) {
        // User pressed escape and only one menu is shown, cancel it.
        Cancel(EXIT_OUTERMOST);
        return false;
      }
      CloseSubmenu();
      break;

    default:
      break;
  }
  return true;
}

MenuController::MenuController(ui::NativeTheme* theme,
                               bool blocking,
                               internal::MenuControllerDelegate* delegate)
    : blocking_run_(blocking),
      showing_(false),
      exit_type_(EXIT_NONE),
      did_capture_(false),
      result_(NULL),
      accept_event_flags_(0),
      drop_target_(NULL),
      drop_position_(MenuDelegate::DROP_UNKNOWN),
      owner_(NULL),
      possible_drag_(false),
      drag_in_progress_(false),
      valid_drop_coordinates_(false),
      last_drop_operation_(MenuDelegate::DROP_UNKNOWN),
      showing_submenu_(false),
      menu_button_(NULL),
      active_mouse_view_id_(ViewStorage::GetInstance()->CreateStorageID()),
      delegate_(delegate),
      message_loop_depth_(0),
      menu_config_(theme),
      closing_event_time_(base::TimeDelta()),
      menu_start_time_(base::TimeTicks()),
      is_combobox_(false),
      item_selected_by_touch_(false) {
  active_instance_ = this;
}

MenuController::~MenuController() {
  DCHECK(!showing_);
  if (owner_)
    owner_->RemoveObserver(this);
  if (active_instance_ == this)
    active_instance_ = NULL;
  StopShowTimer();
  StopCancelAllTimer();
}

void MenuController::RunMessageLoop(bool nested_menu) {
  internal::MenuMessagePumpDispatcher nested_dispatcher(this);

  // |owner_| may be NULL.
  aura::Window* root = GetOwnerRootWindow(owner_);
  if (root) {
    scoped_ptr<ActivationChangeObserverImpl> observer;
    if (!nested_menu)
      observer.reset(new ActivationChangeObserverImpl(this, root));
    aura::client::GetDispatcherClient(root)
        ->RunWithDispatcher(&nested_dispatcher);
  } else {
    base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
    base::MessageLoop::ScopedNestableTaskAllower allow(loop);
    base::RunLoop run_loop(&nested_dispatcher);
    run_loop.Run();
  }
}

MenuController::SendAcceleratorResultType
    MenuController::SendAcceleratorToHotTrackedView() {
  CustomButton* hot_view = GetFirstHotTrackedView(pending_state_.item);
  if (!hot_view)
    return ACCELERATOR_NOT_PROCESSED;

  ui::Accelerator accelerator(ui::VKEY_RETURN, ui::EF_NONE);
  hot_view->AcceleratorPressed(accelerator);
  CustomButton* button = static_cast<CustomButton*>(hot_view);
  button->SetHotTracked(true);
  return (exit_type_ == EXIT_NONE) ?
      ACCELERATOR_PROCESSED : ACCELERATOR_PROCESSED_EXIT;
}

void MenuController::UpdateInitialLocation(
    const gfx::Rect& bounds,
    MenuItemView::AnchorPosition position,
    bool context_menu) {
  pending_state_.context_menu = context_menu;
  pending_state_.initial_bounds = bounds;
  if (bounds.height() > 1) {
    // Inset the bounds slightly, otherwise drag coordinates don't line up
    // nicely and menus close prematurely.
    pending_state_.initial_bounds.Inset(0, 1);
  }

  // Reverse anchor position for RTL languages.
  if (base::i18n::IsRTL() &&
      (position == MenuItemView::TOPRIGHT ||
       position == MenuItemView::TOPLEFT)) {
    pending_state_.anchor = position == MenuItemView::TOPRIGHT ?
        MenuItemView::TOPLEFT : MenuItemView::TOPRIGHT;
  } else {
    pending_state_.anchor = position;
  }

  // Calculate the bounds of the monitor we'll show menus on. Do this once to
  // avoid repeated system queries for the info.
  pending_state_.monitor_bounds = GetScreen()->GetDisplayNearestPoint(
      bounds.origin()).work_area();
#if defined(USE_ASH)
  if (!pending_state_.monitor_bounds.Contains(bounds)) {
    // Use the monitor area if the work area doesn't contain the bounds. This
    // handles showing a menu from the launcher.
    gfx::Rect monitor_area = GetScreen()->GetDisplayNearestPoint(
        bounds.origin()).bounds();
    if (monitor_area.Contains(bounds))
      pending_state_.monitor_bounds = monitor_area;
  }
#endif
}

void MenuController::Accept(MenuItemView* item, int event_flags) {
  DCHECK(IsBlockingRun());
  result_ = item;
  if (item && !menu_stack_.empty() &&
      !item->GetDelegate()->ShouldCloseAllMenusOnExecute(item->GetCommand())) {
    SetExitType(EXIT_OUTERMOST);
  } else {
    SetExitType(EXIT_ALL);
  }
  accept_event_flags_ = event_flags;
}

bool MenuController::ShowSiblingMenu(SubmenuView* source,
                                     const gfx::Point& mouse_location) {
  if (!menu_stack_.empty() || !menu_button_)
    return false;

  View* source_view = source->GetScrollViewContainer();
  if (mouse_location.x() >= 0 &&
      mouse_location.x() < source_view->width() &&
      mouse_location.y() >= 0 &&
      mouse_location.y() < source_view->height()) {
    // The mouse is over the menu, no need to continue.
    return false;
  }

  gfx::NativeWindow window_under_mouse = GetScreen()->GetWindowUnderCursor();
  // TODO(oshima): Replace with views only API.
  if (!owner_ || window_under_mouse != owner_->GetNativeWindow())
    return false;

  // The user moved the mouse outside the menu and over the owning window. See
  // if there is a sibling menu we should show.
  gfx::Point screen_point(mouse_location);
  View::ConvertPointToScreen(source_view, &screen_point);
  MenuItemView::AnchorPosition anchor;
  bool has_mnemonics;
  MenuButton* button = NULL;
  MenuItemView* alt_menu = source->GetMenuItem()->GetDelegate()->
      GetSiblingMenu(source->GetMenuItem()->GetRootMenuItem(),
                     screen_point, &anchor, &has_mnemonics, &button);
  if (!alt_menu || (state_.item && state_.item->GetRootMenuItem() == alt_menu))
    return false;

  delegate_->SiblingMenuCreated(alt_menu);

  if (!button) {
    // If the delegate returns a menu, they must also return a button.
    NOTREACHED();
    return false;
  }

  // There is a sibling menu, update the button state, hide the current menu
  // and show the new one.
  menu_button_->SetState(CustomButton::STATE_NORMAL);
  menu_button_->SchedulePaint();
  menu_button_ = button;
  menu_button_->SetState(CustomButton::STATE_PRESSED);
  menu_button_->SchedulePaint();

  // Need to reset capture when we show the menu again, otherwise we aren't
  // going to get any events.
  did_capture_ = false;
  gfx::Point screen_menu_loc;
  View::ConvertPointToScreen(button, &screen_menu_loc);

  // It is currently not possible to show a submenu recursively in a bubble.
  DCHECK(!MenuItemView::IsBubble(anchor));
  // Subtract 1 from the height to make the popup flush with the button border.
  UpdateInitialLocation(gfx::Rect(screen_menu_loc.x(), screen_menu_loc.y(),
                                  button->width(), button->height() - 1),
                        anchor, state_.context_menu);
  alt_menu->PrepareForRun(
      false, has_mnemonics,
      source->GetMenuItem()->GetRootMenuItem()->show_mnemonics_);
  alt_menu->controller_ = this;
  SetSelection(alt_menu, SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
  return true;
}

bool MenuController::ShowContextMenu(MenuItemView* menu_item,
                                     SubmenuView* source,
                                     const ui::LocatedEvent& event,
                                     ui::MenuSourceType source_type) {
  // Set the selection immediately, making sure the submenu is only open
  // if it already was.
  int selection_types = SELECTION_UPDATE_IMMEDIATELY;
  if (state_.item == pending_state_.item && state_.submenu_open)
    selection_types |= SELECTION_OPEN_SUBMENU;
  SetSelection(pending_state_.item, selection_types);
  gfx::Point loc(event.location());
  View::ConvertPointToScreen(source->GetScrollViewContainer(), &loc);

  if (menu_item->GetDelegate()->ShowContextMenu(
          menu_item, menu_item->GetCommand(), loc, source_type)) {
    SendMouseCaptureLostToActiveView();
    return true;
  }
  return false;
}

void MenuController::CloseAllNestedMenus() {
  for (std::list<State>::iterator i = menu_stack_.begin();
       i != menu_stack_.end(); ++i) {
    MenuItemView* last_item = i->item;
    for (MenuItemView* item = last_item; item;
         item = item->GetParentMenuItem()) {
      CloseMenu(item);
      last_item = item;
    }
    i->submenu_open = false;
    i->item = last_item;
  }
}

MenuItemView* MenuController::GetMenuItemAt(View* source, int x, int y) {
  // Walk the view hierarchy until we find a menu item (or the root).
  View* child_under_mouse = source->GetEventHandlerForPoint(gfx::Point(x, y));
  while (child_under_mouse &&
         child_under_mouse->id() != MenuItemView::kMenuItemViewID) {
    child_under_mouse = child_under_mouse->parent();
  }
  if (child_under_mouse && child_under_mouse->enabled() &&
      child_under_mouse->id() == MenuItemView::kMenuItemViewID) {
    return static_cast<MenuItemView*>(child_under_mouse);
  }
  return NULL;
}

MenuItemView* MenuController::GetEmptyMenuItemAt(View* source, int x, int y) {
  View* child_under_mouse = source->GetEventHandlerForPoint(gfx::Point(x, y));
  if (child_under_mouse &&
      child_under_mouse->id() == MenuItemView::kEmptyMenuItemViewID) {
    return static_cast<MenuItemView*>(child_under_mouse);
  }
  return NULL;
}

bool MenuController::IsScrollButtonAt(SubmenuView* source,
                                      int x,
                                      int y,
                                      MenuPart::Type* part) {
  MenuScrollViewContainer* scroll_view = source->GetScrollViewContainer();
  View* child_under_mouse =
      scroll_view->GetEventHandlerForPoint(gfx::Point(x, y));
  if (child_under_mouse && child_under_mouse->enabled()) {
    if (child_under_mouse == scroll_view->scroll_up_button()) {
      *part = MenuPart::SCROLL_UP;
      return true;
    }
    if (child_under_mouse == scroll_view->scroll_down_button()) {
      *part = MenuPart::SCROLL_DOWN;
      return true;
    }
  }
  return false;
}

MenuController::MenuPart MenuController::GetMenuPart(
    SubmenuView* source,
    const gfx::Point& source_loc) {
  gfx::Point screen_loc(source_loc);
  View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);
  return GetMenuPartByScreenCoordinateUsingMenu(state_.item, screen_loc);
}

MenuController::MenuPart MenuController::GetMenuPartByScreenCoordinateUsingMenu(
    MenuItemView* item,
    const gfx::Point& screen_loc) {
  MenuPart part;
  for (; item; item = item->GetParentMenuItem()) {
    if (item->HasSubmenu() && item->GetSubmenu()->IsShowing() &&
        GetMenuPartByScreenCoordinateImpl(item->GetSubmenu(), screen_loc,
                                          &part)) {
      return part;
    }
  }
  return part;
}

bool MenuController::GetMenuPartByScreenCoordinateImpl(
    SubmenuView* menu,
    const gfx::Point& screen_loc,
    MenuPart* part) {
  // Is the mouse over the scroll buttons?
  gfx::Point scroll_view_loc = screen_loc;
  View* scroll_view_container = menu->GetScrollViewContainer();
  View::ConvertPointFromScreen(scroll_view_container, &scroll_view_loc);
  if (scroll_view_loc.x() < 0 ||
      scroll_view_loc.x() >= scroll_view_container->width() ||
      scroll_view_loc.y() < 0 ||
      scroll_view_loc.y() >= scroll_view_container->height()) {
    // Point isn't contained in menu.
    return false;
  }
  if (IsScrollButtonAt(menu, scroll_view_loc.x(), scroll_view_loc.y(),
                       &(part->type))) {
    part->submenu = menu;
    return true;
  }

  // Not over the scroll button. Check the actual menu.
  if (DoesSubmenuContainLocation(menu, screen_loc)) {
    gfx::Point menu_loc = screen_loc;
    View::ConvertPointFromScreen(menu, &menu_loc);
    part->menu = GetMenuItemAt(menu, menu_loc.x(), menu_loc.y());
    part->type = MenuPart::MENU_ITEM;
    part->submenu = menu;
    if (!part->menu)
      part->parent = menu->GetMenuItem();
    return true;
  }

  // While the mouse isn't over a menu item or the scroll buttons of menu, it
  // is contained by menu and so we return true. If we didn't return true other
  // menus would be searched, even though they are likely obscured by us.
  return true;
}

bool MenuController::DoesSubmenuContainLocation(SubmenuView* submenu,
                                                const gfx::Point& screen_loc) {
  gfx::Point view_loc = screen_loc;
  View::ConvertPointFromScreen(submenu, &view_loc);
  gfx::Rect vis_rect = submenu->GetVisibleBounds();
  return vis_rect.Contains(view_loc.x(), view_loc.y());
}

void MenuController::CommitPendingSelection() {
  StopShowTimer();

  size_t paths_differ_at = 0;
  std::vector<MenuItemView*> current_path;
  std::vector<MenuItemView*> new_path;
  BuildPathsAndCalculateDiff(state_.item, pending_state_.item, &current_path,
                             &new_path, &paths_differ_at);

  // Hide the old menu.
  for (size_t i = paths_differ_at; i < current_path.size(); ++i) {
    if (current_path[i]->HasSubmenu()) {
      current_path[i]->GetSubmenu()->Hide();
    }
  }

  // Copy pending to state_, making sure to preserve the direction menus were
  // opened.
  std::list<bool> pending_open_direction;
  state_.open_leading.swap(pending_open_direction);
  state_ = pending_state_;
  state_.open_leading.swap(pending_open_direction);

  int menu_depth = MenuDepth(state_.item);
  if (menu_depth == 0) {
    state_.open_leading.clear();
  } else {
    int cached_size = static_cast<int>(state_.open_leading.size());
    DCHECK_GE(menu_depth, 0);
    while (cached_size-- >= menu_depth)
      state_.open_leading.pop_back();
  }

  if (!state_.item) {
    // Nothing to select.
    StopScrolling();
    return;
  }

  // Open all the submenus preceeding the last menu item (last menu item is
  // handled next).
  if (new_path.size() > 1) {
    for (std::vector<MenuItemView*>::iterator i = new_path.begin();
         i != new_path.end() - 1; ++i) {
      OpenMenu(*i);
    }
  }

  if (state_.submenu_open) {
    // The submenu should be open, open the submenu if the item has a submenu.
    if (state_.item->HasSubmenu()) {
      OpenMenu(state_.item);
    } else {
      state_.submenu_open = false;
    }
  } else if (state_.item->HasSubmenu() &&
             state_.item->GetSubmenu()->IsShowing()) {
    state_.item->GetSubmenu()->Hide();
  }

  if (scroll_task_.get() && scroll_task_->submenu()) {
    // Stop the scrolling if none of the elements of the selection contain
    // the menu being scrolled.
    bool found = false;
    for (MenuItemView* item = state_.item; item && !found;
         item = item->GetParentMenuItem()) {
      found = (item->HasSubmenu() && item->GetSubmenu()->IsShowing() &&
               item->GetSubmenu() == scroll_task_->submenu());
    }
    if (!found)
      StopScrolling();
  }
}

void MenuController::CloseMenu(MenuItemView* item) {
  DCHECK(item);
  if (!item->HasSubmenu())
    return;
  item->GetSubmenu()->Hide();
}

void MenuController::OpenMenu(MenuItemView* item) {
  DCHECK(item);
  if (item->GetSubmenu()->IsShowing()) {
    return;
  }

  OpenMenuImpl(item, true);
  did_capture_ = true;
}

void MenuController::OpenMenuImpl(MenuItemView* item, bool show) {
  // TODO(oshima|sky): Don't show the menu if drag is in progress and
  // this menu doesn't support drag drop. See crbug.com/110495.
  if (show) {
    int old_count = item->GetSubmenu()->child_count();
    item->GetDelegate()->WillShowMenu(item);
    if (old_count != item->GetSubmenu()->child_count()) {
      // If the number of children changed then we may need to add empty items.
      item->AddEmptyMenus();
    }
  }
  bool prefer_leading =
      state_.open_leading.empty() ? true : state_.open_leading.back();
  bool resulting_direction;
  gfx::Rect bounds = MenuItemView::IsBubble(state_.anchor) ?
      CalculateBubbleMenuBounds(item, prefer_leading, &resulting_direction) :
      CalculateMenuBounds(item, prefer_leading, &resulting_direction);
  state_.open_leading.push_back(resulting_direction);
  bool do_capture = (!did_capture_ && blocking_run_);
  showing_submenu_ = true;
  if (show) {
    // Menus are the only place using kGroupingPropertyKey, so any value (other
    // than 0) is fine.
    const int kGroupingId = 1001;
    item->GetSubmenu()->ShowAt(owner_, bounds, do_capture);
    item->GetSubmenu()->GetWidget()->SetNativeWindowProperty(
        TooltipManager::kGroupingPropertyKey,
        reinterpret_cast<void*>(kGroupingId));
  } else {
    item->GetSubmenu()->Reposition(bounds);
  }
  showing_submenu_ = false;
}

void MenuController::MenuChildrenChanged(MenuItemView* item) {
  DCHECK(item);
  // Menu shouldn't be updated during drag operation.
  DCHECK(!GetActiveMouseView());

  // If the current item or pending item is a descendant of the item
  // that changed, move the selection back to the changed item.
  const MenuItemView* ancestor = state_.item;
  while (ancestor && ancestor != item)
    ancestor = ancestor->GetParentMenuItem();
  if (!ancestor) {
    ancestor = pending_state_.item;
    while (ancestor && ancestor != item)
      ancestor = ancestor->GetParentMenuItem();
    if (!ancestor)
      return;
  }
  SetSelection(item, SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
  if (item->HasSubmenu())
    OpenMenuImpl(item, false);
}

void MenuController::BuildPathsAndCalculateDiff(
    MenuItemView* old_item,
    MenuItemView* new_item,
    std::vector<MenuItemView*>* old_path,
    std::vector<MenuItemView*>* new_path,
    size_t* first_diff_at) {
  DCHECK(old_path && new_path && first_diff_at);
  BuildMenuItemPath(old_item, old_path);
  BuildMenuItemPath(new_item, new_path);

  size_t common_size = std::min(old_path->size(), new_path->size());

  // Find the first difference between the two paths, when the loop
  // returns, diff_i is the first index where the two paths differ.
  for (size_t i = 0; i < common_size; ++i) {
    if ((*old_path)[i] != (*new_path)[i]) {
      *first_diff_at = i;
      return;
    }
  }

  *first_diff_at = common_size;
}

void MenuController::BuildMenuItemPath(MenuItemView* item,
                                       std::vector<MenuItemView*>* path) {
  if (!item)
    return;
  BuildMenuItemPath(item->GetParentMenuItem(), path);
  path->push_back(item);
}

void MenuController::StartShowTimer() {
  show_timer_.Start(FROM_HERE,
                    TimeDelta::FromMilliseconds(menu_config_.show_delay),
                    this, &MenuController::CommitPendingSelection);
}

void MenuController::StopShowTimer() {
  show_timer_.Stop();
}

void MenuController::StartCancelAllTimer() {
  cancel_all_timer_.Start(FROM_HERE,
                          TimeDelta::FromMilliseconds(kCloseOnExitTime),
                          this, &MenuController::CancelAll);
}

void MenuController::StopCancelAllTimer() {
  cancel_all_timer_.Stop();
}

gfx::Rect MenuController::CalculateMenuBounds(MenuItemView* item,
                                              bool prefer_leading,
                                              bool* is_leading) {
  DCHECK(item);

  SubmenuView* submenu = item->GetSubmenu();
  DCHECK(submenu);

  gfx::Size pref = submenu->GetScrollViewContainer()->GetPreferredSize();

  // Don't let the menu go too wide.
  pref.set_width(std::min(pref.width(),
                            item->GetDelegate()->GetMaxWidthForMenu(item)));
  if (!state_.monitor_bounds.IsEmpty())
    pref.set_width(std::min(pref.width(), state_.monitor_bounds.width()));

  // Assume we can honor prefer_leading.
  *is_leading = prefer_leading;

  int x, y;

  const MenuConfig& menu_config = item->GetMenuConfig();

  if (!item->GetParentMenuItem()) {
    // First item, position relative to initial location.
    x = state_.initial_bounds.x();

    // Offsets for context menu prevent menu items being selected by
    // simply opening the menu (bug 142992).
    if (menu_config.offset_context_menus && state_.context_menu)
      x += 1;

    y = state_.initial_bounds.bottom();
    if (state_.anchor == MenuItemView::TOPRIGHT) {
      x = x + state_.initial_bounds.width() - pref.width();
      if (menu_config.offset_context_menus && state_.context_menu)
        x -= 1;
    } else if (state_.anchor == MenuItemView::BOTTOMCENTER) {
      x = x - (pref.width() - state_.initial_bounds.width()) / 2;
      if (pref.height() >
          state_.initial_bounds.y() + kCenteredContextMenuYOffset) {
        // Menu does not fit above the anchor. We move it to below.
        y = state_.initial_bounds.y() - kCenteredContextMenuYOffset;
      } else {
        y = std::max(0, state_.initial_bounds.y() - pref.height()) +
            kCenteredContextMenuYOffset;
      }
    }

    if (!state_.monitor_bounds.IsEmpty() &&
        y + pref.height() > state_.monitor_bounds.bottom()) {
      // The menu doesn't fit fully below the button on the screen. The menu
      // position with respect to the bounds will be preserved if it has
      // already been drawn. When the requested positioning is below the bounds
      // it will shrink the menu to make it fit below.
      // If the requested positioning is best fit, it will first try to fit the
      // menu below. If that does not fit it will try to place it above. If
      // that will not fit it will place it at the bottom of the work area and
      // moving it off the initial_bounds region to avoid overlap.
      // In all other requested position styles it will be flipped above and
      // the height will be shrunken to the usable height.
      if (item->actual_menu_position() == MenuItemView::POSITION_BELOW_BOUNDS) {
        pref.set_height(std::min(pref.height(),
                                 state_.monitor_bounds.bottom() - y));
      } else if (item->actual_menu_position() ==
                 MenuItemView::POSITION_BEST_FIT) {
        MenuItemView::MenuPosition orientation =
            MenuItemView::POSITION_BELOW_BOUNDS;
        if (state_.monitor_bounds.height() < pref.height()) {
          // Handle very tall menus.
          pref.set_height(state_.monitor_bounds.height());
          y = state_.monitor_bounds.y();
        } else if (state_.monitor_bounds.y() + pref.height() <
            state_.initial_bounds.y()) {
          // Flipping upwards if there is enough space.
          y = state_.initial_bounds.y() - pref.height();
          orientation = MenuItemView::POSITION_ABOVE_BOUNDS;
        } else {
          // It is allowed to move the menu a bit around in order to get the
          // best fit and to avoid showing scroll elements.
          y = state_.monitor_bounds.bottom() - pref.height();
        }
        if (orientation == MenuItemView::POSITION_BELOW_BOUNDS) {
          // The menu should never overlap the owning button. So move it.
          // We use the anchor view style to determine the preferred position
          // relative to the owning button.
          if (state_.anchor == MenuItemView::TOPLEFT) {
            // The menu starts with the same x coordinate as the owning button.
            if (x + state_.initial_bounds.width() + pref.width() >
                state_.monitor_bounds.right())
              x -= pref.width();  // Move the menu to the left of the button.
            else
              x += state_.initial_bounds.width(); // Move the menu right.
          } else {
            // The menu should end with the same x coordinate as the owning
            // button.
            if (state_.monitor_bounds.x() >
                state_.initial_bounds.x() - pref.width())
              x = state_.initial_bounds.right();  // Move right of the button.
            else
              x = state_.initial_bounds.x() - pref.width(); // Move left.
          }
        }
        item->set_actual_menu_position(orientation);
      } else {
        pref.set_height(std::min(pref.height(),
            state_.initial_bounds.y() - state_.monitor_bounds.y()));
        y = state_.initial_bounds.y() - pref.height();
        item->set_actual_menu_position(MenuItemView::POSITION_ABOVE_BOUNDS);
      }
    } else if (item->actual_menu_position() ==
               MenuItemView::POSITION_ABOVE_BOUNDS) {
      pref.set_height(std::min(pref.height(),
          state_.initial_bounds.y() - state_.monitor_bounds.y()));
      y = state_.initial_bounds.y() - pref.height();
    } else {
      item->set_actual_menu_position(MenuItemView::POSITION_BELOW_BOUNDS);
    }
    if (state_.monitor_bounds.width() != 0 &&
        menu_config.offset_context_menus && state_.context_menu) {
      if (x + pref.width() > state_.monitor_bounds.right())
        x = state_.initial_bounds.x() - pref.width() - 1;
      if (x < state_.monitor_bounds.x())
        x = state_.monitor_bounds.x();
    }
  } else {
    // Not the first menu; position it relative to the bounds of the menu
    // item.
    gfx::Point item_loc;
    View::ConvertPointToScreen(item, &item_loc);

    // We must make sure we take into account the UI layout. If the layout is
    // RTL, then a 'leading' menu is positioned to the left of the parent menu
    // item and not to the right.
    bool layout_is_rtl = base::i18n::IsRTL();
    bool create_on_the_right = (prefer_leading && !layout_is_rtl) ||
                               (!prefer_leading && layout_is_rtl);
    int submenu_horizontal_inset = menu_config.submenu_horizontal_inset;

    if (create_on_the_right) {
      x = item_loc.x() + item->width() - submenu_horizontal_inset;
      if (state_.monitor_bounds.width() != 0 &&
          x + pref.width() > state_.monitor_bounds.right()) {
        if (layout_is_rtl)
          *is_leading = true;
        else
          *is_leading = false;
        x = item_loc.x() - pref.width() + submenu_horizontal_inset;
      }
    } else {
      x = item_loc.x() - pref.width() + submenu_horizontal_inset;
      if (state_.monitor_bounds.width() != 0 && x < state_.monitor_bounds.x()) {
        if (layout_is_rtl)
          *is_leading = false;
        else
          *is_leading = true;
        x = item_loc.x() + item->width() - submenu_horizontal_inset;
      }
    }
    y = item_loc.y() - menu_config.menu_vertical_border_size;
    if (state_.monitor_bounds.width() != 0) {
      pref.set_height(std::min(pref.height(), state_.monitor_bounds.height()));
      if (y + pref.height() > state_.monitor_bounds.bottom())
        y = state_.monitor_bounds.bottom() - pref.height();
      if (y < state_.monitor_bounds.y())
        y = state_.monitor_bounds.y();
    }
  }

  if (state_.monitor_bounds.width() != 0) {
    if (x + pref.width() > state_.monitor_bounds.right())
      x = state_.monitor_bounds.right() - pref.width();
    if (x < state_.monitor_bounds.x())
      x = state_.monitor_bounds.x();
  }
  return gfx::Rect(x, y, pref.width(), pref.height());
}

gfx::Rect MenuController::CalculateBubbleMenuBounds(MenuItemView* item,
                                                    bool prefer_leading,
                                                    bool* is_leading) {
  DCHECK(item);
  DCHECK(!item->GetParentMenuItem());

  // Assume we can honor prefer_leading.
  *is_leading = prefer_leading;

  SubmenuView* submenu = item->GetSubmenu();
  DCHECK(submenu);

  gfx::Size pref = submenu->GetScrollViewContainer()->GetPreferredSize();
  const gfx::Rect& owner_bounds = pending_state_.initial_bounds;

  // First the size gets reduced to the possible space.
  if (!state_.monitor_bounds.IsEmpty()) {
    int max_width = state_.monitor_bounds.width();
    int max_height = state_.monitor_bounds.height();
    // In case of bubbles, the maximum width is limited by the space
    // between the display corner and the target area + the tip size.
    if (state_.anchor == MenuItemView::BUBBLE_LEFT) {
      max_width = owner_bounds.x() - state_.monitor_bounds.x() +
                  kBubbleTipSizeLeftRight;
    } else if (state_.anchor == MenuItemView::BUBBLE_RIGHT) {
      max_width = state_.monitor_bounds.right() - owner_bounds.right() +
                  kBubbleTipSizeLeftRight;
    } else if (state_.anchor == MenuItemView::BUBBLE_ABOVE) {
      max_height = owner_bounds.y() - state_.monitor_bounds.y() +
                   kBubbleTipSizeTopBottom;
    } else if (state_.anchor == MenuItemView::BUBBLE_BELOW) {
      max_height = state_.monitor_bounds.bottom() - owner_bounds.bottom() +
                   kBubbleTipSizeTopBottom;
    }
    // The space for the menu to cover should never get empty.
    DCHECK_GE(max_width, kBubbleTipSizeLeftRight);
    DCHECK_GE(max_height, kBubbleTipSizeTopBottom);
    pref.set_width(std::min(pref.width(), max_width));
    pref.set_height(std::min(pref.height(), max_height));
  }
  // Also make sure that the menu does not go too wide.
  pref.set_width(std::min(pref.width(),
                          item->GetDelegate()->GetMaxWidthForMenu(item)));

  int x, y;
  if (state_.anchor == MenuItemView::BUBBLE_ABOVE ||
      state_.anchor == MenuItemView::BUBBLE_BELOW) {
    if (state_.anchor == MenuItemView::BUBBLE_ABOVE)
      y = owner_bounds.y() - pref.height() + kBubbleTipSizeTopBottom;
    else
      y = owner_bounds.bottom() - kBubbleTipSizeTopBottom;

    x = owner_bounds.CenterPoint().x() - pref.width() / 2;
    int x_old = x;
    if (x < state_.monitor_bounds.x()) {
      x = state_.monitor_bounds.x();
    } else if (x + pref.width() > state_.monitor_bounds.right()) {
      x = state_.monitor_bounds.right() - pref.width();
    }
    submenu->GetScrollViewContainer()->SetBubbleArrowOffset(
        pref.width() / 2 - x + x_old);
  } else {
    if (state_.anchor == MenuItemView::BUBBLE_RIGHT)
      x = owner_bounds.right() - kBubbleTipSizeLeftRight;
    else
      x = owner_bounds.x() - pref.width() + kBubbleTipSizeLeftRight;

    y = owner_bounds.CenterPoint().y() - pref.height() / 2;
    int y_old = y;
    if (y < state_.monitor_bounds.y()) {
      y = state_.monitor_bounds.y();
    } else if (y + pref.height() > state_.monitor_bounds.bottom()) {
      y = state_.monitor_bounds.bottom() - pref.height();
    }
    submenu->GetScrollViewContainer()->SetBubbleArrowOffset(
        pref.height() / 2 - y + y_old);
  }
  return gfx::Rect(x, y, pref.width(), pref.height());
}

// static
int MenuController::MenuDepth(MenuItemView* item) {
  return item ? (MenuDepth(item->GetParentMenuItem()) + 1) : 0;
}

void MenuController::IncrementSelection(int delta) {
  MenuItemView* item = pending_state_.item;
  DCHECK(item);
  if (pending_state_.submenu_open && item->HasSubmenu() &&
      item->GetSubmenu()->IsShowing()) {
    // A menu is selected and open, but none of its children are selected,
    // select the first menu item.
    if (item->GetSubmenu()->GetMenuItemCount()) {
      SetSelection(item->GetSubmenu()->GetMenuItemAt(0), SELECTION_DEFAULT);
      return;
    }
  }

  if (item->has_children()) {
    CustomButton* button = GetFirstHotTrackedView(item);
    if (button) {
      button->SetHotTracked(false);
      View* to_make_hot = GetNextFocusableView(item, button, delta == 1);
      CustomButton* button_hot = CustomButton::AsCustomButton(to_make_hot);
      if (button_hot) {
        button_hot->SetHotTracked(true);
        return;
      }
    } else {
      View* to_make_hot = GetInitialFocusableView(item, delta == 1);
      CustomButton* button_hot = CustomButton::AsCustomButton(to_make_hot);
      if (button_hot) {
        button_hot->SetHotTracked(true);
        return;
      }
    }
  }

  MenuItemView* parent = item->GetParentMenuItem();
  if (parent) {
    int parent_count = parent->GetSubmenu()->GetMenuItemCount();
    if (parent_count > 1) {
      for (int i = 0; i < parent_count; ++i) {
        if (parent->GetSubmenu()->GetMenuItemAt(i) == item) {
          MenuItemView* to_select =
              FindNextSelectableMenuItem(parent, i, delta);
          if (!to_select)
            break;
          SetSelection(to_select, SELECTION_DEFAULT);
          View* to_make_hot = GetInitialFocusableView(to_select, delta == 1);
          CustomButton* button_hot = CustomButton::AsCustomButton(to_make_hot);
          if (button_hot)
            button_hot->SetHotTracked(true);
          break;
        }
      }
    }
  }
}

MenuItemView* MenuController::FindNextSelectableMenuItem(MenuItemView* parent,
                                                         int index,
                                                         int delta) {
  int start_index = index;
  int parent_count = parent->GetSubmenu()->GetMenuItemCount();
  // Loop through the menu items skipping any invisible menus. The loop stops
  // when we wrap or find a visible child.
  do {
    index = (index + delta + parent_count) % parent_count;
    if (index == start_index)
      return NULL;
    MenuItemView* child = parent->GetSubmenu()->GetMenuItemAt(index);
    if (child->visible())
      return child;
  } while (index != start_index);
  return NULL;
}

void MenuController::OpenSubmenuChangeSelectionIfCan() {
  MenuItemView* item = pending_state_.item;
  if (item->HasSubmenu() && item->enabled()) {
    if (item->GetSubmenu()->GetMenuItemCount() > 0) {
      SetSelection(item->GetSubmenu()->GetMenuItemAt(0),
                   SELECTION_UPDATE_IMMEDIATELY);
    } else {
      // No menu items, just show the sub-menu.
      SetSelection(item, SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
    }
  }
}

void MenuController::CloseSubmenu() {
  MenuItemView* item = state_.item;
  DCHECK(item);
  if (!item->GetParentMenuItem())
    return;
  if (item->HasSubmenu() && item->GetSubmenu()->IsShowing())
    SetSelection(item, SELECTION_UPDATE_IMMEDIATELY);
  else if (item->GetParentMenuItem()->GetParentMenuItem())
    SetSelection(item->GetParentMenuItem(), SELECTION_UPDATE_IMMEDIATELY);
}

MenuController::SelectByCharDetails MenuController::FindChildForMnemonic(
    MenuItemView* parent,
    base::char16 key,
    bool (*match_function)(MenuItemView* menu, base::char16 mnemonic)) {
  SubmenuView* submenu = parent->GetSubmenu();
  DCHECK(submenu);
  SelectByCharDetails details;

  for (int i = 0, menu_item_count = submenu->GetMenuItemCount();
       i < menu_item_count; ++i) {
    MenuItemView* child = submenu->GetMenuItemAt(i);
    if (child->enabled() && child->visible()) {
      if (child == pending_state_.item)
        details.index_of_item = i;
      if (match_function(child, key)) {
        if (details.first_match == -1)
          details.first_match = i;
        else
          details.has_multiple = true;
        if (details.next_match == -1 && details.index_of_item != -1 &&
            i > details.index_of_item)
          details.next_match = i;
      }
    }
  }
  return details;
}

bool MenuController::AcceptOrSelect(MenuItemView* parent,
                                    const SelectByCharDetails& details) {
  // This should only be invoked if there is a match.
  DCHECK(details.first_match != -1);
  DCHECK(parent->HasSubmenu());
  SubmenuView* submenu = parent->GetSubmenu();
  DCHECK(submenu);
  if (!details.has_multiple) {
    // There's only one match, activate it (or open if it has a submenu).
    if (submenu->GetMenuItemAt(details.first_match)->HasSubmenu()) {
      SetSelection(submenu->GetMenuItemAt(details.first_match),
                   SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
    } else {
      Accept(submenu->GetMenuItemAt(details.first_match), 0);
      return true;
    }
  } else if (details.index_of_item == -1 || details.next_match == -1) {
    SetSelection(submenu->GetMenuItemAt(details.first_match),
                 SELECTION_DEFAULT);
  } else {
    SetSelection(submenu->GetMenuItemAt(details.next_match),
                 SELECTION_DEFAULT);
  }
  return false;
}

bool MenuController::SelectByChar(base::char16 character) {
  base::char16 char_array[] = { character, 0 };
  base::char16 key = base::i18n::ToLower(char_array)[0];
  MenuItemView* item = pending_state_.item;
  if (!item->HasSubmenu() || !item->GetSubmenu()->IsShowing())
    item = item->GetParentMenuItem();
  DCHECK(item);
  DCHECK(item->HasSubmenu());
  DCHECK(item->GetSubmenu());
  if (item->GetSubmenu()->GetMenuItemCount() == 0)
    return false;

  // Look for matches based on mnemonic first.
  SelectByCharDetails details =
      FindChildForMnemonic(item, key, &MatchesMnemonic);
  if (details.first_match != -1)
    return AcceptOrSelect(item, details);

  if (is_combobox_) {
    item->GetSubmenu()->GetTextInputClient()->InsertChar(character, 0);
  } else {
    // If no mnemonics found, look at first character of titles.
    details = FindChildForMnemonic(item, key, &TitleMatchesMnemonic);
    if (details.first_match != -1)
      return AcceptOrSelect(item, details);
  }

  return false;
}

void MenuController::RepostEvent(SubmenuView* source,
                                 const ui::LocatedEvent& event) {
  gfx::Point screen_loc(event.location());
  View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);

  gfx::NativeView native_view = source->GetWidget()->GetNativeView();
  gfx::Screen* screen = gfx::Screen::GetScreenFor(native_view);
  gfx::NativeWindow window = screen->GetWindowAtScreenPoint(screen_loc);

  // On Windows, it is ok for window to be NULL. Please refer to the
  // RepostLocatedEvent function for more information.
#if defined(OS_WIN)
  // Release the capture.
  SubmenuView* submenu = state_.item->GetRootMenuItem()->GetSubmenu();
  submenu->ReleaseCapture();

  gfx::NativeView view = submenu->GetWidget()->GetNativeView();
  if (view && window) {
    DWORD view_tid = GetWindowThreadProcessId(HWNDForNativeView(view), NULL);
    if (view_tid != GetWindowThreadProcessId(HWNDForNativeView(window), NULL)) {
      // Even though we have mouse capture, windows generates a mouse event if
      // the other window is in a separate thread. Only repost an event if
      // |view| was created on the same thread, else the target window can get
      // double events leading to bad behavior.
      return;
    }
  }
#else
  if (!window)
    return;
#endif

  scoped_ptr<ui::LocatedEvent> clone;
  if (event.IsMouseEvent()) {
    clone.reset(new ui::MouseEvent(static_cast<const ui::MouseEvent&>(event)));
  } else if (event.IsGestureEvent()) {
    // TODO(rbyers): Gesture event repost is tricky to get right
    // crbug.com/170987.
    return;
  } else {
    NOTREACHED();
    return;
  }
  clone->set_location(screen_loc);

  RepostLocatedEvent(window, *clone);
}


void MenuController::SetDropMenuItem(
    MenuItemView* new_target,
    MenuDelegate::DropPosition new_position) {
  if (new_target == drop_target_ && new_position == drop_position_)
    return;

  if (drop_target_) {
    drop_target_->GetParentMenuItem()->GetSubmenu()->SetDropMenuItem(
        NULL, MenuDelegate::DROP_NONE);
  }
  drop_target_ = new_target;
  drop_position_ = new_position;
  if (drop_target_) {
    drop_target_->GetParentMenuItem()->GetSubmenu()->SetDropMenuItem(
        drop_target_, drop_position_);
  }
}

void MenuController::UpdateScrolling(const MenuPart& part) {
  if (!part.is_scroll() && !scroll_task_.get())
    return;

  if (!scroll_task_.get())
    scroll_task_.reset(new MenuScrollTask());
  scroll_task_->Update(part);
}

void MenuController::StopScrolling() {
  scroll_task_.reset(NULL);
}

void MenuController::UpdateActiveMouseView(SubmenuView* event_source,
                                           const ui::MouseEvent& event,
                                           View* target_menu) {
  View* target = NULL;
  gfx::Point target_menu_loc(event.location());
  if (target_menu && target_menu->has_children()) {
    // Locate the deepest child view to send events to.  This code assumes we
    // don't have to walk up the tree to find a view interested in events. This
    // is currently true for the cases we are embedding views, but if we embed
    // more complex hierarchies it'll need to change.
    View::ConvertPointToScreen(event_source->GetScrollViewContainer(),
                               &target_menu_loc);
    View::ConvertPointFromScreen(target_menu, &target_menu_loc);
    target = target_menu->GetEventHandlerForPoint(target_menu_loc);
    if (target == target_menu || !target->enabled())
      target = NULL;
  }
  View* active_mouse_view = GetActiveMouseView();
  if (target != active_mouse_view) {
    SendMouseCaptureLostToActiveView();
    active_mouse_view = target;
    SetActiveMouseView(active_mouse_view);
    if (active_mouse_view) {
      gfx::Point target_point(target_menu_loc);
      View::ConvertPointToTarget(
          target_menu, active_mouse_view, &target_point);
      ui::MouseEvent mouse_entered_event(ui::ET_MOUSE_ENTERED,
                                         target_point, target_point,
                                         0, 0);
      active_mouse_view->OnMouseEntered(mouse_entered_event);

      ui::MouseEvent mouse_pressed_event(ui::ET_MOUSE_PRESSED,
                                         target_point, target_point,
                                         event.flags(),
                                         event.changed_button_flags());
      active_mouse_view->OnMousePressed(mouse_pressed_event);
    }
  }

  if (active_mouse_view) {
    gfx::Point target_point(target_menu_loc);
    View::ConvertPointToTarget(target_menu, active_mouse_view, &target_point);
    ui::MouseEvent mouse_dragged_event(ui::ET_MOUSE_DRAGGED,
                                       target_point, target_point,
                                       event.flags(),
                                       event.changed_button_flags());
    active_mouse_view->OnMouseDragged(mouse_dragged_event);
  }
}

void MenuController::SendMouseReleaseToActiveView(SubmenuView* event_source,
                                                  const ui::MouseEvent& event) {
  View* active_mouse_view = GetActiveMouseView();
  if (!active_mouse_view)
    return;

  gfx::Point target_loc(event.location());
  View::ConvertPointToScreen(event_source->GetScrollViewContainer(),
                             &target_loc);
  View::ConvertPointFromScreen(active_mouse_view, &target_loc);
  ui::MouseEvent release_event(ui::ET_MOUSE_RELEASED, target_loc, target_loc,
                               event.flags(), event.changed_button_flags());
  // Reset active mouse view before sending mouse released. That way if it calls
  // back to us, we aren't in a weird state.
  SetActiveMouseView(NULL);
  active_mouse_view->OnMouseReleased(release_event);
}

void MenuController::SendMouseCaptureLostToActiveView() {
  View* active_mouse_view = GetActiveMouseView();
  if (!active_mouse_view)
    return;

  // Reset the active_mouse_view_ before sending mouse capture lost. That way if
  // it calls back to us, we aren't in a weird state.
  SetActiveMouseView(NULL);
  active_mouse_view->OnMouseCaptureLost();
}

void MenuController::SetActiveMouseView(View* view) {
  if (view)
    ViewStorage::GetInstance()->StoreView(active_mouse_view_id_, view);
  else
    ViewStorage::GetInstance()->RemoveView(active_mouse_view_id_);
}

View* MenuController::GetActiveMouseView() {
  return ViewStorage::GetInstance()->RetrieveView(active_mouse_view_id_);
}

void MenuController::SetExitType(ExitType type) {
  exit_type_ = type;
  // Exit nested message loops as soon as possible. We do this as
  // MessagePumpDispatcher is only invoked before native events, which means
  // its entirely possible for a Widget::CloseNow() task to be processed before
  // the next native message. We quite the nested message loop as soon as
  // possible to avoid having deleted views classes (such as widgets and
  // rootviews) on the stack when the nested message loop stops.
  //
  // It's safe to invoke QuitNestedMessageLoop() multiple times, it only effects
  // the current loop.
  bool quit_now = ShouldQuitNow() && exit_type_ != EXIT_NONE &&
      message_loop_depth_;

  if (quit_now) {
    if (owner_) {
      aura::Window* root = owner_->GetNativeWindow()->GetRootWindow();
      aura::client::GetDispatcherClient(root)->QuitNestedMessageLoop();
    } else {
      base::MessageLoop::current()->QuitNow();
    }
  }
}

bool MenuController::ShouldQuitNow() const {
  aura::Window* root = GetOwnerRootWindow(owner_);
  return !aura::client::GetDragDropClient(root) ||
         !aura::client::GetDragDropClient(root)->IsDragDropInProgress();
}

void MenuController::HandleMouseLocation(SubmenuView* source,
                                         const gfx::Point& mouse_location) {
  if (showing_submenu_)
    return;

  // Ignore mouse events if we're closing the menu.
  if (exit_type_ != EXIT_NONE)
    return;

  MenuPart part = GetMenuPart(source, mouse_location);

  UpdateScrolling(part);

  if (!blocking_run_)
    return;

  if (part.type == MenuPart::NONE && ShowSiblingMenu(source, mouse_location))
    return;

  if (part.type == MenuPart::MENU_ITEM && part.menu) {
    SetSelection(part.menu, SELECTION_OPEN_SUBMENU);
  } else if (!part.is_scroll() && pending_state_.item &&
             pending_state_.item->GetParentMenuItem() &&
             (!pending_state_.item->HasSubmenu() ||
              !pending_state_.item->GetSubmenu()->IsShowing())) {
    // On exit if the user hasn't selected an item with a submenu, move the
    // selection back to the parent menu item.
    SetSelection(pending_state_.item->GetParentMenuItem(),
                 SELECTION_OPEN_SUBMENU);
  }
}

gfx::Screen* MenuController::GetScreen() {
  aura::Window* root = GetOwnerRootWindow(owner_);
  return root ? gfx::Screen::GetScreenFor(root)
              : gfx::Screen::GetNativeScreen();
}

}  // namespace views

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