ash/login/ui/login_base_bubble_view.cc - chromium/src - Git at Google

 // Copyright 2017 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 "ash/login/ui/login_base_bubble_view.h"

 #include <memory>

 #include "ash/login/ui/views_utils.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/shell.h"
 #include "ash/style/ash_color_provider.h"
 #include "ui/accessibility/ax_enums.mojom.h"
 #include "ui/aura/client/focus_change_observer.h"
 #include "ui/aura/client/focus_client.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animator.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/views/animation/ink_drop.h"
 #include "ui/views/background.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/wm/core/coordinate_conversion.h"

 namespace ash {
 namespace {

 // Total width of the bubble view.
 constexpr int kBubbleTotalWidthDp = 192;

 // Padding around the bubble view.
 constexpr int kBubblePaddingDp = 16;

 // Spacing between the child view inside the bubble view.
 constexpr int kBubbleBetweenChildSpacingDp = 16;

 // Border radius of the rounded bubble.
 constexpr int kBubbleBorderRadius = 8;

 // The amount of time for bubble show/hide animation.
 constexpr base::TimeDelta kBubbleAnimationDuration = base::Milliseconds(300);

 }  // namespace

 // This class handles keyboard, mouse, and focus events, and dismisses the
 // associated bubble in response.
 class LoginBubbleHandler : public ui::EventHandler {
  public:
   explicit LoginBubbleHandler(LoginBaseBubbleView* bubble) : bubble_(bubble) {
     Shell::Get()->AddPreTargetHandler(this);
   }

   LoginBubbleHandler(const LoginBubbleHandler&) = delete;
   LoginBubbleHandler& operator=(const LoginBubbleHandler&) = delete;

   ~LoginBubbleHandler() override { Shell::Get()->RemovePreTargetHandler(this); }

   // ui::EventHandler:
   void OnMouseEvent(ui::MouseEvent* event) override {
     if (event->type() == ui::ET_MOUSE_PRESSED)
       ProcessPressedEvent(event->AsLocatedEvent());
   }

   void OnGestureEvent(ui::GestureEvent* event) override {
     if (event->type() == ui::ET_GESTURE_TAP ||
         event->type() == ui::ET_GESTURE_TAP_DOWN) {
       ProcessPressedEvent(event->AsLocatedEvent());
     }
   }

   void OnKeyEvent(ui::KeyEvent* event) override {
     if (event->type() != ui::ET_KEY_PRESSED ||
         event->key_code() == ui::VKEY_PROCESSKEY) {
       return;
     }

     if (!bubble_->GetVisible())
       return;

     // Hide the bubble if the bubble opener is about to lose focus from tab
     // traversal.
     if (bubble_->GetBubbleOpener() && bubble_->GetBubbleOpener()->HasFocus() &&
         event->key_code() != ui::VKEY_TAB) {
       return;
     }

     if (login_views_utils::HasFocusInAnyChildView(bubble_))
       return;

     if (!bubble_->is_persistent())
       bubble_->Hide();
   }

  private:
   void ProcessPressedEvent(const ui::LocatedEvent* event) {
     if (!bubble_->GetVisible())
       return;

     gfx::Point screen_location = event->location();
     ::wm::ConvertPointToScreen(static_cast<aura::Window*>(event->target()),
                                &screen_location);

     // Don't do anything with clicks inside the bubble.
     if (bubble_->GetBoundsInScreen().Contains(screen_location))
       return;

     // Let the bubble opener handle clicks on itself.
     if (bubble_->GetBubbleOpener() &&
         bubble_->GetBubbleOpener()->GetBoundsInScreen().Contains(
             screen_location)) {
       return;
     }

     if (!bubble_->is_persistent())
       bubble_->Hide();
   }

   LoginBaseBubbleView* bubble_;
 };

 LoginBaseBubbleView::LoginBaseBubbleView(views::View* anchor_view)
     : LoginBaseBubbleView(anchor_view, nullptr) {}

 LoginBaseBubbleView::LoginBaseBubbleView(views::View* anchor_view,
                                          aura::Window* parent_window)
     : anchor_view_(anchor_view),
       bubble_handler_(std::make_unique<LoginBubbleHandler>(this)) {
   views::BoxLayout* layout_manager =
       SetLayoutManager(std::make_unique<views::BoxLayout>(
           views::BoxLayout::Orientation::kVertical,
           gfx::Insets(kBubblePaddingDp), kBubbleBetweenChildSpacingDp));
   layout_manager->set_cross_axis_alignment(
       views::BoxLayout::CrossAxisAlignment::kStart);

   SetVisible(false);
 }

 void LoginBaseBubbleView::EnsureLayer() {
   if (layer())
     return;
   // Layer rendering is needed for animation.
   SetPaintToLayer();
   SkColor background_color = AshColorProvider::Get()->GetBaseLayerColor(
       AshColorProvider::BaseLayerType::kTransparent80);
   SetBackground(views::CreateRoundedRectBackground(background_color,
                                                    kBubbleBorderRadius));
   layer()->SetBackgroundBlur(ColorProvider::kBackgroundBlurSigma);
   layer()->SetFillsBoundsOpaquely(false);
 }

 LoginBaseBubbleView::~LoginBaseBubbleView() = default;

 void LoginBaseBubbleView::Show() {
   if (layer())
     layer()->GetAnimator()->RemoveObserver(this);

   SetSize(GetPreferredSize());
   SetPosition(CalculatePosition());

   ScheduleAnimation(true /*visible*/);

   // Tell ChromeVox to read bubble contents.
   if (notify_a11y_alert_on_show_) {
     NotifyAccessibilityEvent(ax::mojom::Event::kAlert,
                              true /*send_native_event*/);
   }
 }

 void LoginBaseBubbleView::Hide() {
   ScheduleAnimation(false /*visible*/);
 }

 LoginButton* LoginBaseBubbleView::GetBubbleOpener() const {
   return nullptr;
 }

 gfx::Point LoginBaseBubbleView::CalculatePosition() {
   if (!GetAnchorView())
     return gfx::Point();

   // Views' positions are defined in the parents' coordinate system. Therefore,
   // the position of the bubble needs to be returned in its parent's coordinate
   // system. kTryBeforeThenAfter and kTryAfterThenBefore use strategies implying
   // to know the bounds of the entire window; therefore, resulting position is
   // calculated by using the root view's coordinates system. kShowAbove and
   // kShowBelow are less complicated, they only use the coordinate system of the
   // the anchor view's parent.

   // In RTL case, we are doing mirroring in `ConvertPointToTarget` when finding
   // the position of the bubble. However, there's no need to mirror since the
   // coordinate system is from right to left and the origin is the right upper
   // corner. `GetMirroredXWithWidthInView` is called to cancel out the mirroring
   // effect and returning the correct position for the bubble.
   gfx::Point anchor_position = GetAnchorView()->bounds().origin();
   gfx::Point origin;
   ConvertPointToTarget(GetAnchorView()->parent() /*source*/,
                        GetAnchorView()->GetWidget()->GetRootView() /*target*/,
                        &origin);
   origin.set_x(parent()->GetMirroredXWithWidthInView(
       origin.x(), GetAnchorView()->parent()->width()));
   anchor_position += origin.OffsetFromOrigin();
   auto bounds = GetBoundsAvailableToShowBubble();
   gfx::Size bubble_size(width() + 2 * horizontal_padding_,
                         height() + vertical_padding_);

   gfx::Point result;
   View* source;
   switch (positioning_strategy_) {
     case PositioningStrategy::kTryBeforeThenAfter:
       result = login_views_utils::CalculateBubblePositionBeforeAfterStrategy(
           {anchor_position, GetAnchorView()->size()}, bubble_size, bounds);
       source = GetAnchorView()->GetWidget()->GetRootView();
       break;
     case PositioningStrategy::kTryAfterThenBefore:
       result = login_views_utils::CalculateBubblePositionAfterBeforeStrategy(
           {anchor_position, GetAnchorView()->size()}, bubble_size, bounds);
       source = GetAnchorView()->GetWidget()->GetRootView();
       break;
     case PositioningStrategy::kShowAbove: {
       gfx::Point top_center = GetAnchorView()->bounds().top_center();
       result = top_center - gfx::Vector2d(GetPreferredSize().width() / 2,
                                           GetPreferredSize().height());
       source = GetAnchorView()->parent();
       break;
     }
     case PositioningStrategy::kShowBelow: {
       result = GetAnchorView()->bounds().bottom_left();
       source = GetAnchorView()->parent();
       break;
     }
   }
   // Get position of the bubble surrounded by paddings.
   result.Offset(horizontal_padding_, 0);
   ConvertPointToTarget(source /*source*/, parent() /*target*/, &result);
   return result;
 }

 void LoginBaseBubbleView::SetAnchorView(views::View* anchor_view) {
   anchor_view_ = anchor_view;
 }

 void LoginBaseBubbleView::OnLayerAnimationEnded(
     ui::LayerAnimationSequence* sequence) {
   layer()->GetAnimator()->RemoveObserver(this);
   SetVisible(false);
   DestroyLayer();
 }

 void LoginBaseBubbleView::OnLayerAnimationAborted(
     ui::LayerAnimationSequence* sequence) {
   // The animation for this view should never be aborted.
   NOTREACHED();
 }

 gfx::Size LoginBaseBubbleView::CalculatePreferredSize() const {
   gfx::Size size;
   size.set_width(kBubbleTotalWidthDp);
   size.set_height(GetHeightForWidth(kBubbleTotalWidthDp));
   return size;
 }

 void LoginBaseBubbleView::Layout() {
   views::View::Layout();

   // If a Layout() is called while the bubble is visible (i.e. due to Show()),
   // its bounds may change because of the parent's LayoutManager. This allows
   // the bubbles to always determine their own size and position.
   if (GetVisible()) {
     SetSize(GetPreferredSize());
     SetPosition(CalculatePosition());
   }
 }

 void LoginBaseBubbleView::OnBlur() {
   Hide();
 }

 void LoginBaseBubbleView::OnThemeChanged() {
   views::View::OnThemeChanged();
   SkColor background_color = AshColorProvider::Get()->GetBaseLayerColor(
       AshColorProvider::BaseLayerType::kTransparent80);
   SetBackground(views::CreateRoundedRectBackground(background_color,
                                                    kBubbleBorderRadius));
 }

 void LoginBaseBubbleView::SetPadding(int horizontal_padding,
                                      int vertical_padding) {
   horizontal_padding_ = horizontal_padding;
   vertical_padding_ = vertical_padding;
 }

 gfx::Rect LoginBaseBubbleView::GetBoundsAvailableToShowBubble() const {
   auto bounds = GetRootViewBounds();
   auto work_area = GetWorkArea();
   // Get min means here to exclude either shelf or virtual keyaboard.
   bounds.set_height(std::min(bounds.height(), work_area.height()));
   return bounds;
 }

 gfx::Rect LoginBaseBubbleView::GetRootViewBounds() const {
   return GetAnchorView()->GetWidget()->GetRootView()->GetLocalBounds();
 }

 gfx::Rect LoginBaseBubbleView::GetWorkArea() const {
   return display::Screen::GetScreen()
       ->GetDisplayNearestWindow(GetAnchorView()->GetWidget()->GetNativeWindow())
       .work_area();
 }

 void LoginBaseBubbleView::ScheduleAnimation(bool visible) {
   if (GetBubbleOpener()) {
     views::InkDrop::Get(GetBubbleOpener())
         ->AnimateToState(visible ? views::InkDropState::ACTIVATED
                                  : views::InkDropState::DEACTIVATED,
                          nullptr /*event*/);
   }

   if (layer())
     layer()->GetAnimator()->StopAnimating();

   EnsureLayer();
   float opacity_start = 0.0f;
   float opacity_end = 1.0f;
   if (!visible) {
     std::swap(opacity_start, opacity_end);
     // We only need to handle animation ending if we're hiding the bubble.
     layer()->GetAnimator()->AddObserver(this);
   } else {
     SetVisible(true);
   }

   layer()->SetOpacity(opacity_start);
   {
     ui::ScopedLayerAnimationSettings settings(layer()->GetAnimator());
     settings.SetTransitionDuration(kBubbleAnimationDuration);
     settings.SetTweenType(visible ? gfx::Tween::EASE_OUT : gfx::Tween::EASE_IN);
     settings.SetPreemptionStrategy(
         ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
     layer()->SetOpacity(opacity_end);
   }
 }

 }  // namespace ash
	// Copyright 2017 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 "ash/login/ui/login_base_bubble_view.h"

	#include <memory>

	#include "ash/login/ui/views_utils.h"
	#include "ash/public/cpp/shell_window_ids.h"
	#include "ash/shell.h"
	#include "ash/style/ash_color_provider.h"
	#include "ui/accessibility/ax_enums.mojom.h"
	#include "ui/aura/client/focus_change_observer.h"
	#include "ui/aura/client/focus_client.h"
	#include "ui/compositor/layer.h"
	#include "ui/compositor/layer_animator.h"
	#include "ui/compositor/scoped_layer_animation_settings.h"
	#include "ui/events/event_handler.h"
	#include "ui/gfx/geometry/point.h"
	#include "ui/views/animation/ink_drop.h"
	#include "ui/views/background.h"
	#include "ui/views/layout/box_layout.h"
	#include "ui/wm/core/coordinate_conversion.h"

	namespace ash {
	namespace {

	// Total width of the bubble view.
	constexpr int kBubbleTotalWidthDp = 192;

	// Padding around the bubble view.
	constexpr int kBubblePaddingDp = 16;

	// Spacing between the child view inside the bubble view.
	constexpr int kBubbleBetweenChildSpacingDp = 16;

	// Border radius of the rounded bubble.
	constexpr int kBubbleBorderRadius = 8;

	// The amount of time for bubble show/hide animation.
	constexpr base::TimeDelta kBubbleAnimationDuration = base::Milliseconds(300);

	} // namespace

	// This class handles keyboard, mouse, and focus events, and dismisses the
	// associated bubble in response.
	class LoginBubbleHandler : public ui::EventHandler {
	public:
	explicit LoginBubbleHandler(LoginBaseBubbleView* bubble) : bubble_(bubble) {
	Shell::Get()->AddPreTargetHandler(this);
	}

	LoginBubbleHandler(const LoginBubbleHandler&) = delete;
	LoginBubbleHandler& operator=(const LoginBubbleHandler&) = delete;

	~LoginBubbleHandler() override { Shell::Get()->RemovePreTargetHandler(this); }

	// ui::EventHandler:
	void OnMouseEvent(ui::MouseEvent* event) override {
	if (event->type() == ui::ET_MOUSE_PRESSED)
	ProcessPressedEvent(event->AsLocatedEvent());
	}

	void OnGestureEvent(ui::GestureEvent* event) override {
	if (event->type() == ui::ET_GESTURE_TAP \|\|
	event->type() == ui::ET_GESTURE_TAP_DOWN) {
	ProcessPressedEvent(event->AsLocatedEvent());
	}
	}

	void OnKeyEvent(ui::KeyEvent* event) override {
	if (event->type() != ui::ET_KEY_PRESSED \|\|
	event->key_code() == ui::VKEY_PROCESSKEY) {
	return;
	}

	if (!bubble_->GetVisible())
	return;

	// Hide the bubble if the bubble opener is about to lose focus from tab
	// traversal.
	if (bubble_->GetBubbleOpener() && bubble_->GetBubbleOpener()->HasFocus() &&
	event->key_code() != ui::VKEY_TAB) {
	return;
	}

	if (login_views_utils::HasFocusInAnyChildView(bubble_))
	return;

	if (!bubble_->is_persistent())
	bubble_->Hide();
	}

	private:
	void ProcessPressedEvent(const ui::LocatedEvent* event) {
	if (!bubble_->GetVisible())
	return;

	gfx::Point screen_location = event->location();
	::wm::ConvertPointToScreen(static_cast<aura::Window*>(event->target()),
	&screen_location);

	// Don't do anything with clicks inside the bubble.
	if (bubble_->GetBoundsInScreen().Contains(screen_location))
	return;

	// Let the bubble opener handle clicks on itself.
	if (bubble_->GetBubbleOpener() &&
	bubble_->GetBubbleOpener()->GetBoundsInScreen().Contains(
	screen_location)) {
	return;
	}

	if (!bubble_->is_persistent())
	bubble_->Hide();
	}

	LoginBaseBubbleView* bubble_;
	};

	LoginBaseBubbleView::LoginBaseBubbleView(views::View* anchor_view)
	: LoginBaseBubbleView(anchor_view, nullptr) {}

	LoginBaseBubbleView::LoginBaseBubbleView(views::View* anchor_view,
	aura::Window* parent_window)
	: anchor_view_(anchor_view),
	bubble_handler_(std::make_unique<LoginBubbleHandler>(this)) {
	views::BoxLayout* layout_manager =
	SetLayoutManager(std::make_unique<views::BoxLayout>(
	views::BoxLayout::Orientation::kVertical,
	gfx::Insets(kBubblePaddingDp), kBubbleBetweenChildSpacingDp));
	layout_manager->set_cross_axis_alignment(
	views::BoxLayout::CrossAxisAlignment::kStart);

	SetVisible(false);
	}

	void LoginBaseBubbleView::EnsureLayer() {
	if (layer())
	return;
	// Layer rendering is needed for animation.
	SetPaintToLayer();
	SkColor background_color = AshColorProvider::Get()->GetBaseLayerColor(
	AshColorProvider::BaseLayerType::kTransparent80);
	SetBackground(views::CreateRoundedRectBackground(background_color,
	kBubbleBorderRadius));
	layer()->SetBackgroundBlur(ColorProvider::kBackgroundBlurSigma);
	layer()->SetFillsBoundsOpaquely(false);
	}

	LoginBaseBubbleView::~LoginBaseBubbleView() = default;

	void LoginBaseBubbleView::Show() {
	if (layer())
	layer()->GetAnimator()->RemoveObserver(this);

	SetSize(GetPreferredSize());
	SetPosition(CalculatePosition());

	ScheduleAnimation(true /visible/);

	// Tell ChromeVox to read bubble contents.
	if (notify_a11y_alert_on_show_) {
	NotifyAccessibilityEvent(ax::mojom::Event::kAlert,
	true /send_native_event/);
	}
	}

	void LoginBaseBubbleView::Hide() {
	ScheduleAnimation(false /visible/);
	}

	LoginButton* LoginBaseBubbleView::GetBubbleOpener() const {
	return nullptr;
	}

	gfx::Point LoginBaseBubbleView::CalculatePosition() {
	if (!GetAnchorView())
	return gfx::Point();

	// Views' positions are defined in the parents' coordinate system. Therefore,
	// the position of the bubble needs to be returned in its parent's coordinate
	// system. kTryBeforeThenAfter and kTryAfterThenBefore use strategies implying
	// to know the bounds of the entire window; therefore, resulting position is
	// calculated by using the root view's coordinates system. kShowAbove and
	// kShowBelow are less complicated, they only use the coordinate system of the
	// the anchor view's parent.

	// In RTL case, we are doing mirroring in `ConvertPointToTarget` when finding
	// the position of the bubble. However, there's no need to mirror since the
	// coordinate system is from right to left and the origin is the right upper
	// corner. `GetMirroredXWithWidthInView` is called to cancel out the mirroring
	// effect and returning the correct position for the bubble.
	gfx::Point anchor_position = GetAnchorView()->bounds().origin();
	gfx::Point origin;
	ConvertPointToTarget(GetAnchorView()->parent() /source/,
	GetAnchorView()->GetWidget()->GetRootView() /target/,
	&origin);
	origin.set_x(parent()->GetMirroredXWithWidthInView(
	origin.x(), GetAnchorView()->parent()->width()));
	anchor_position += origin.OffsetFromOrigin();
	auto bounds = GetBoundsAvailableToShowBubble();
	gfx::Size bubble_size(width() + 2 * horizontal_padding_,
	height() + vertical_padding_);

	gfx::Point result;
	View* source;
	switch (positioning_strategy_) {
	case PositioningStrategy::kTryBeforeThenAfter:
	result = login_views_utils::CalculateBubblePositionBeforeAfterStrategy(
	{anchor_position, GetAnchorView()->size()}, bubble_size, bounds);
	source = GetAnchorView()->GetWidget()->GetRootView();
	break;
	case PositioningStrategy::kTryAfterThenBefore:
	result = login_views_utils::CalculateBubblePositionAfterBeforeStrategy(
	{anchor_position, GetAnchorView()->size()}, bubble_size, bounds);
	source = GetAnchorView()->GetWidget()->GetRootView();
	break;
	case PositioningStrategy::kShowAbove: {
	gfx::Point top_center = GetAnchorView()->bounds().top_center();
	result = top_center - gfx::Vector2d(GetPreferredSize().width() / 2,
	GetPreferredSize().height());
	source = GetAnchorView()->parent();
	break;
	}
	case PositioningStrategy::kShowBelow: {
	result = GetAnchorView()->bounds().bottom_left();
	source = GetAnchorView()->parent();
	break;
	}
	}
	// Get position of the bubble surrounded by paddings.
	result.Offset(horizontal_padding_, 0);
	ConvertPointToTarget(source /source/, parent() /target/, &result);
	return result;
	}

	void LoginBaseBubbleView::SetAnchorView(views::View* anchor_view) {
	anchor_view_ = anchor_view;
	}

	void LoginBaseBubbleView::OnLayerAnimationEnded(
	ui::LayerAnimationSequence* sequence) {
	layer()->GetAnimator()->RemoveObserver(this);
	SetVisible(false);
	DestroyLayer();
	}

	void LoginBaseBubbleView::OnLayerAnimationAborted(
	ui::LayerAnimationSequence* sequence) {
	// The animation for this view should never be aborted.
	NOTREACHED();
	}

	gfx::Size LoginBaseBubbleView::CalculatePreferredSize() const {
	gfx::Size size;
	size.set_width(kBubbleTotalWidthDp);
	size.set_height(GetHeightForWidth(kBubbleTotalWidthDp));
	return size;
	}

	void LoginBaseBubbleView::Layout() {
	views::View::Layout();

	// If a Layout() is called while the bubble is visible (i.e. due to Show()),
	// its bounds may change because of the parent's LayoutManager. This allows
	// the bubbles to always determine their own size and position.
	if (GetVisible()) {
	SetSize(GetPreferredSize());
	SetPosition(CalculatePosition());
	}
	}

	void LoginBaseBubbleView::OnBlur() {
	Hide();
	}

	void LoginBaseBubbleView::OnThemeChanged() {
	views::View::OnThemeChanged();
	SkColor background_color = AshColorProvider::Get()->GetBaseLayerColor(
	AshColorProvider::BaseLayerType::kTransparent80);
	SetBackground(views::CreateRoundedRectBackground(background_color,
	kBubbleBorderRadius));
	}

	void LoginBaseBubbleView::SetPadding(int horizontal_padding,
	int vertical_padding) {
	horizontal_padding_ = horizontal_padding;
	vertical_padding_ = vertical_padding;
	}

	gfx::Rect LoginBaseBubbleView::GetBoundsAvailableToShowBubble() const {
	auto bounds = GetRootViewBounds();
	auto work_area = GetWorkArea();
	// Get min means here to exclude either shelf or virtual keyaboard.
	bounds.set_height(std::min(bounds.height(), work_area.height()));
	return bounds;
	}

	gfx::Rect LoginBaseBubbleView::GetRootViewBounds() const {
	return GetAnchorView()->GetWidget()->GetRootView()->GetLocalBounds();
	}

	gfx::Rect LoginBaseBubbleView::GetWorkArea() const {
	return display::Screen::GetScreen()
	->GetDisplayNearestWindow(GetAnchorView()->GetWidget()->GetNativeWindow())
	.work_area();
	}

	void LoginBaseBubbleView::ScheduleAnimation(bool visible) {
	if (GetBubbleOpener()) {
	views::InkDrop::Get(GetBubbleOpener())
	->AnimateToState(visible ? views::InkDropState::ACTIVATED
	: views::InkDropState::DEACTIVATED,
	nullptr /event/);
	}

	if (layer())
	layer()->GetAnimator()->StopAnimating();

	EnsureLayer();
	float opacity_start = 0.0f;
	float opacity_end = 1.0f;
	if (!visible) {
	std::swap(opacity_start, opacity_end);
	// We only need to handle animation ending if we're hiding the bubble.
	layer()->GetAnimator()->AddObserver(this);
	} else {
	SetVisible(true);
	}

	layer()->SetOpacity(opacity_start);
	{
	ui::ScopedLayerAnimationSettings settings(layer()->GetAnimator());
	settings.SetTransitionDuration(kBubbleAnimationDuration);
	settings.SetTweenType(visible ? gfx::Tween::EASE_OUT : gfx::Tween::EASE_IN);
	settings.SetPreemptionStrategy(
	ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
	layer()->SetOpacity(opacity_end);
	}
	}

	} // namespace ash