Removed use of ButtonListener in favor of a set callback.

Bug: 772945
Change-Id: I3ef3c5d1dda8d9d37ce165323fdcd384cbe8c5d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2468944
Commit-Queue: Allen Bauer <kylixrd@chromium.org>
Commit-Queue: Tao Wu <wutao@chromium.org>
Reviewed-by: Tao Wu <wutao@chromium.org>
Auto-Submit: Allen Bauer <kylixrd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816825}

ash/assistant/test/assistant_ash_test_base.cc

@@ -24,6 +24,7 @@
 #include "ash/test/ash_test_helper.h"
 #include "base/run_loop.h"
 #include "base/test/task_environment.h"
+#include "ui/views/view_utils.h"
 
 namespace ash {
 
@@ -66,8 +67,7 @@ void PressHomeButton() {
 // This includes direct and indirect children.
 // For this class to work, _ChildView must:
 //      * Inherit from |views::View|.
-//      * Have a static variable called |kClassName|.
-//      * Return |_ChildView::kClassName| from its GetClassName() method.
+//      * Implement view metadata (see comments on views::View).
 template <class _ChildView>
 class ChildViewCollector {
  public:
@@ -84,7 +84,7 @@ class ChildViewCollector {
 
  private:
   void Get(views::View* view, Views* result) {
-    if (view->GetClassName() == _ChildView::kClassName)
+    if (views::IsViewClass<_ChildView>(view))
       result->push_back(static_cast<_ChildView*>(view));
     for (views::View* child : view->children())
       Get(child, result);

ash/assistant/ui/base/assistant_button.cc

@@ -7,6 +7,7 @@
 #include "ash/assistant/model/assistant_ui_model.h"
 #include "ash/assistant/ui/base/assistant_button_listener.h"
 #include "ash/assistant/util/histogram_util.h"
+#include "base/bind.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/paint_vector_icon.h"
@@ -34,7 +35,10 @@ AssistantButton::InitParams::~InitParams() = default;
 
 AssistantButton::AssistantButton(AssistantButtonListener* listener,
                                  AssistantButtonId button_id)
-    : views::ImageButton(this), listener_(listener), id_(button_id) {
+    : views::ImageButton(base::BindRepeating(&AssistantButton::OnButtonPressed,
+                                             base::Unretained(this))),
+      listener_(listener),
+      id_(button_id) {
   constexpr SkColor kInkDropBaseColor = SK_ColorBLACK;
   constexpr float kInkDropVisibleOpacity = 0.06f;
 
@@ -121,8 +125,7 @@ std::unique_ptr<views::InkDropRipple> AssistantButton::CreateInkDropRipple()
       GetInkDropBaseColor(), GetInkDropVisibleOpacity());
 }
 
-void AssistantButton::ButtonPressed(views::Button* sender,
-                                    const ui::Event& event) {
+void AssistantButton::OnButtonPressed() {
   assistant::util::IncrementAssistantButtonClickCount(id_);
   listener_->OnButtonPressed(id_);
 }

ash/assistant/ui/base/assistant_button.h

@@ -28,8 +28,7 @@ class AssistantButtonListener;
 enum class AssistantButtonId;
 
 class COMPONENT_EXPORT(ASSISTANT_UI) AssistantButton
-    : public views::ImageButton,
-      public views::ButtonListener {
+    : public views::ImageButton {
  public:
   // Initialization parameters for customizing the Assistant button.
   struct InitParams {
@@ -56,6 +55,8 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantButton
 
   AssistantButton(AssistantButtonListener* listener,
                   AssistantButtonId button_id);
+  AssistantButton(const AssistantButton&) = delete;
+  AssistantButton& operator=(const AssistantButton&) = delete;
   ~AssistantButton() override;
 
   // Creates a button with the default Assistant styles.
@@ -75,14 +76,11 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantButton
       const override;
   std::unique_ptr<views::InkDropRipple> CreateInkDropRipple() const override;
 
-  // views::ButtonListener:
-  void ButtonPressed(views::Button* sender, const ui::Event& event) override;
-
  private:
+  void OnButtonPressed();
+
   AssistantButtonListener* listener_;
   const AssistantButtonId id_;
-
-  DISALLOW_COPY_AND_ASSIGN(AssistantButton);
 };
 
 }  // namespace ash

ash/assistant/ui/base/assistant_scroll_view.cc

@@ -9,6 +9,7 @@
 
 #include "base/optional.h"
 #include "ui/views/controls/scrollbar/overlay_scroll_bar.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 
 namespace ash {
 
@@ -93,10 +94,6 @@ AssistantScrollView::AssistantScrollView() {
 
 AssistantScrollView::~AssistantScrollView() = default;
 
-const char* AssistantScrollView::GetClassName() const {
-  return "AssistantScrollView";
-}
-
 void AssistantScrollView::OnViewPreferredSizeChanged(views::View* view) {
   DCHECK_EQ(content_view_, view);
 
@@ -131,4 +128,7 @@ void AssistantScrollView::InitLayout() {
       std::make_unique<InvisibleScrollBar>(&observers_, /*horizontal=*/false));
 }
 
+BEGIN_METADATA(AssistantScrollView, views::ScrollView)
+END_METADATA
+
 }  // namespace ash

ash/assistant/ui/base/assistant_scroll_view.h

@@ -8,6 +8,7 @@
 #include "base/component_export.h"
 #include "base/observer_list.h"
 #include "ui/views/controls/scroll_view.h"
+#include "ui/views/metadata/metadata_header_macros.h"
 #include "ui/views/view_observer.h"
 
 namespace ash {
@@ -36,14 +37,13 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantScrollView
     ~Observer() override = default;
   };
 
+  METADATA_HEADER(AssistantScrollView);
+
   AssistantScrollView();
   AssistantScrollView(const AssistantScrollView&) = delete;
   AssistantScrollView& operator=(const AssistantScrollView) = delete;
   ~AssistantScrollView() override;
 
-  // views::ScrollView:
-  const char* GetClassName() const override;
-
   // views::ViewObserver:
   void OnViewPreferredSizeChanged(views::View* view) override;
 

ash/assistant/ui/main_stage/animated_container_view.cc

@@ -14,6 +14,7 @@
 #include "chromeos/services/assistant/public/cpp/features.h"
 #include "ui/compositor/callback_layer_animation_observer.h"
 #include "ui/compositor/layer_animator.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 
 namespace ash {
 
@@ -378,4 +379,7 @@ bool AnimatedContainerView::FadeOutObserverCallback(
   return true;
 }
 
+BEGIN_METADATA(AnimatedContainerView, AssistantScrollView)
+END_METADATA
+
 }  // namespace ash

ash/assistant/ui/main_stage/animated_container_view.h

@@ -15,6 +15,7 @@
 #include "ash/public/cpp/assistant/controller/assistant_controller_observer.h"
 #include "base/scoped_observer.h"
 #include "chromeos/services/assistant/public/cpp/assistant_service.h"
+#include "ui/views/metadata/metadata_header_macros.h"
 
 namespace ui {
 class CallbackLayerAnimationObserver;
@@ -62,7 +63,11 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AnimatedContainerView
  public:
   using AssistantSuggestion = chromeos::assistant::AssistantSuggestion;
 
+  METADATA_HEADER(AnimatedContainerView);
+
   explicit AnimatedContainerView(AssistantViewDelegate* delegate);
+  AnimatedContainerView(const AnimatedContainerView&) = delete;
+  AnimatedContainerView& operator=(const AnimatedContainerView&) = delete;
   ~AnimatedContainerView() override;
 
   // AssistantScrollView:
@@ -168,8 +173,6 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AnimatedContainerView
       assistant_controller_observer_{this};
 
   base::WeakPtrFactory<AnimatedContainerView> weak_factory_{this};
-
-  DISALLOW_COPY_AND_ASSIGN(AnimatedContainerView);
 };
 
 }  // namespace ash

ash/assistant/ui/main_stage/assistant_onboarding_suggestion_view.cc

@@ -7,6 +7,7 @@
 #include "ash/assistant/ui/assistant_ui_constants.h"
 #include "ash/assistant/ui/assistant_view_delegate.h"
 #include "ash/assistant/util/resource_util.h"
+#include "base/bind.h"
 #include "base/stl_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chromeos/services/assistant/public/cpp/assistant_service.h"
@@ -17,6 +18,7 @@
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/layout/flex_layout.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 #include "ui/views/view_class_properties.h"
 
 namespace ash {
@@ -66,14 +68,13 @@ SkColor GetForegroundColor(int index) {
 
 // AssistantOnboardingSuggestionView -------------------------------------------
 
-// static
-constexpr char AssistantOnboardingSuggestionView::kClassName[];
-
 AssistantOnboardingSuggestionView::AssistantOnboardingSuggestionView(
     AssistantViewDelegate* delegate,
     const chromeos::assistant::AssistantSuggestion& suggestion,
     int index)
-    : views::Button(this),
+    : views::Button(base::BindRepeating(
+          &AssistantOnboardingSuggestionView::OnButtonPressed,
+          base::Unretained(this))),
       delegate_(delegate),
       suggestion_id_(suggestion.id),
       index_(index) {
@@ -83,10 +84,6 @@ AssistantOnboardingSuggestionView::AssistantOnboardingSuggestionView(
 AssistantOnboardingSuggestionView::~AssistantOnboardingSuggestionView() =
     default;
 
-const char* AssistantOnboardingSuggestionView::GetClassName() const {
-  return kClassName;
-}
-
 int AssistantOnboardingSuggestionView::GetHeightForWidth(int width) const {
   return kPreferredHeightDip;
 }
@@ -116,11 +113,6 @@ void AssistantOnboardingSuggestionView::RemoveLayerBeneathView(
   ink_drop_container_->RemoveLayerBeneathView(layer);
 }
 
-void AssistantOnboardingSuggestionView::ButtonPressed(views::Button* sender,
-                                                      const ui::Event& event) {
-  delegate_->OnSuggestionPressed(suggestion_id_);
-}
-
 const gfx::ImageSkia& AssistantOnboardingSuggestionView::GetIcon() const {
   return icon_->GetImage();
 }
@@ -227,4 +219,11 @@ void AssistantOnboardingSuggestionView::UpdateIcon(const gfx::ImageSkia& icon) {
     icon_->SetImage(icon);
 }
 
+void AssistantOnboardingSuggestionView::OnButtonPressed() {
+  delegate_->OnSuggestionPressed(suggestion_id_);
+}
+
+BEGIN_METADATA(AssistantOnboardingSuggestionView, views::Button)
+END_METADATA
+
 }  // namespace ash
\ No newline at end of file

ash/assistant/ui/main_stage/assistant_onboarding_suggestion_view.h

@@ -8,6 +8,7 @@
 #include "base/component_export.h"
 #include "base/unguessable_token.h"
 #include "ui/views/controls/button/button.h"
+#include "ui/views/metadata/metadata_header_macros.h"
 
 namespace chromeos {
 namespace assistant {
@@ -26,10 +27,9 @@ namespace ash {
 class AssistantViewDelegate;
 
 class COMPONENT_EXPORT(ASSISTANT_UI) AssistantOnboardingSuggestionView
-    : public views::Button,
-      public views::ButtonListener {
+    : public views::Button {
  public:
-  static constexpr char kClassName[] = "AssistantOnboardingSuggestionView";
+  METADATA_HEADER(AssistantOnboardingSuggestionView);
 
   AssistantOnboardingSuggestionView(
       AssistantViewDelegate* delegate,
@@ -43,15 +43,11 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantOnboardingSuggestionView
   ~AssistantOnboardingSuggestionView() override;
 
   // views::View:
-  const char* GetClassName() const override;
   int GetHeightForWidth(int width) const override;
   void ChildPreferredSizeChanged(views::View* child) override;
   void AddLayerBeneathView(ui::Layer* layer) override;
   void RemoveLayerBeneathView(ui::Layer* layer) override;
 
-  // views::ButtonListener:
-  void ButtonPressed(views::Button* sender, const ui::Event& event) override;
-
   // Returns the icon for the suggestion.
   const gfx::ImageSkia& GetIcon() const;
 
@@ -62,6 +58,8 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantOnboardingSuggestionView
   void InitLayout(const chromeos::assistant::AssistantSuggestion& suggestion);
   void UpdateIcon(const gfx::ImageSkia& icon);
 
+  void OnButtonPressed();
+
   AssistantViewDelegate* const delegate_;  // Owned by AssistantController.
   const base::UnguessableToken suggestion_id_;
   const int index_;

ash/assistant/ui/main_stage/assistant_onboarding_view_unittest.cc

@@ -36,6 +36,7 @@
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
+#include "ui/views/view_utils.h"
 
 namespace ash {
 
@@ -64,7 +65,7 @@ void FindDescendentByClassName(views::View* parent, T** result) {
     auto* candidate = children.front();
     children.pop();
 
-    if (candidate->GetClassName() == T::kClassName) {
+    if (views::IsViewClass<T>(candidate)) {
       *result = static_cast<T*>(candidate);
       return;
     }

ash/assistant/ui/main_stage/assistant_opt_in_view.cc

@@ -11,11 +11,14 @@
 #include "ash/assistant/ui/assistant_view_delegate.h"
 #include "ash/assistant/ui/assistant_view_ids.h"
 #include "ash/strings/grit/ash_strings.h"
+#include "base/bind.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/color_palette.h"
+#include "ui/views/controls/button/button.h"
 #include "ui/views/controls/styled_label.h"
 #include "ui/views/layout/box_layout.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 
 namespace ash {
 
@@ -48,14 +51,20 @@ base::string16 GetAction(int consent_status) {
 
 class AssistantOptInContainer : public views::Button {
  public:
-  explicit AssistantOptInContainer(views::ButtonListener* listener)
-      : views::Button(listener) {
+  METADATA_HEADER(AssistantOptInContainer);
+
+  explicit AssistantOptInContainer(views::Button::PressedCallback callback)
+      : views::Button(callback) {
     constexpr float kHighlightOpacity = 0.06f;
     SetFocusPainter(views::Painter::CreateSolidRoundRectPainter(
         SkColorSetA(SK_ColorBLACK, 0xff * kHighlightOpacity),
         kPreferredHeightDip / 2));
   }
 
+  AssistantOptInContainer(const AssistantOptInContainer&) = delete;
+
+  AssistantOptInContainer& operator=(const AssistantOptInContainer) = delete;
+
   ~AssistantOptInContainer() override = default;
 
   // views::View:
@@ -78,11 +87,11 @@ class AssistantOptInContainer : public views::Button {
     flags.setColor(gfx::kGoogleBlue500);
     canvas->DrawRoundRect(GetContentsBounds(), height() / 2, flags);
   }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(AssistantOptInContainer);
 };
 
+BEGIN_METADATA(AssistantOptInContainer, views::Button)
+END_METADATA
+
 }  // namespace
 
 // AssistantOptInView ----------------------------------------------------------
@@ -98,10 +107,6 @@ AssistantOptInView::~AssistantOptInView() {
   AssistantState::Get()->RemoveObserver(this);
 }
 
-const char* AssistantOptInView::GetClassName() const {
-  return "AssistantOptInView";
-}
-
 void AssistantOptInView::ChildPreferredSizeChanged(views::View* child) {
   PreferredSizeChanged();
 }
@@ -110,11 +115,6 @@ void AssistantOptInView::OnBoundsChanged(const gfx::Rect& previous_bounds) {
   label_->SizeToFit(width());
 }
 
-void AssistantOptInView::ButtonPressed(views::Button* sender,
-                                       const ui::Event& event) {
-  delegate_->OnOptInButtonPressed();
-}
-
 void AssistantOptInView::OnAssistantConsentStatusChanged(int consent_status) {
   UpdateLabel(consent_status);
 }
@@ -132,7 +132,8 @@ void AssistantOptInView::InitLayout() {
 
   // Container.
   container_ = AddChildView(
-      std::make_unique<AssistantOptInContainer>(/*listener=*/this));
+      std::make_unique<AssistantOptInContainer>(base::BindRepeating(
+          &AssistantOptInView::OnButtonPressed, base::Unretained(this))));
 
   layout_manager =
       container_->SetLayoutManager(std::make_unique<views::BoxLayout>(
@@ -187,4 +188,11 @@ void AssistantOptInView::UpdateLabel(int consent_status) {
   container_->SchedulePaint();
 }
 
+void AssistantOptInView::OnButtonPressed() {
+  delegate_->OnOptInButtonPressed();
+}
+
+BEGIN_METADATA(AssistantOptInView, views::View)
+END_METADATA
+
 }  // namespace ash

ash/assistant/ui/main_stage/assistant_opt_in_view.h

@@ -8,9 +8,11 @@
 #include "ash/public/cpp/assistant/assistant_state.h"
 #include "base/component_export.h"
 #include "base/macros.h"
-#include "ui/views/controls/button/button.h"
+#include "ui/views/metadata/metadata_header_macros.h"
+#include "ui/views/view.h"
 
 namespace views {
+class Button;
 class StyledLabel;
 }  // namespace views
 
@@ -22,20 +24,19 @@ class AssistantViewDelegate;
 
 class COMPONENT_EXPORT(ASSISTANT_UI) AssistantOptInView
     : public views::View,
-      public views::ButtonListener,
       public AssistantStateObserver {
  public:
+  METADATA_HEADER(AssistantOptInView);
+
   explicit AssistantOptInView(AssistantViewDelegate* delegate_);
+  AssistantOptInView(const AssistantOptInView&) = delete;
+  AssistantOptInView& operator=(const AssistantOptInView&) = delete;
   ~AssistantOptInView() override;
 
   // views::View:
-  const char* GetClassName() const override;
   void ChildPreferredSizeChanged(views::View* child) override;
   void OnBoundsChanged(const gfx::Rect& previous_bounds) override;
 
-  // views::ButtonListener:
-  void ButtonPressed(views::Button* sender, const ui::Event& event) override;
-
   // AssistantStateObserver:
   void OnAssistantConsentStatusChanged(int consent_status) override;
 
@@ -43,13 +44,13 @@ class COMPONENT_EXPORT(ASSISTANT_UI) AssistantOptInView
   void InitLayout();
   void UpdateLabel(int consent_status);
 
+  void OnButtonPressed();
+
   views::StyledLabel* label_;  // Owned by view hierarchy.
 
   views::Button* container_;
 
   AssistantViewDelegate* delegate_;
-
-  DISALLOW_COPY_AND_ASSIGN(AssistantOptInView);
 };
 
 }  // namespace ash

ash/assistant/ui/main_stage/suggestion_chip_view.cc

@@ -20,6 +20,7 @@
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/layout/box_layout.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 
 namespace ash {
 
@@ -42,22 +43,14 @@ constexpr int kPreferredHeightDip = 32;
 
 // SuggestionChipView ----------------------------------------------------------
 
-// static
-constexpr char SuggestionChipView::kClassName[];
-
 SuggestionChipView::SuggestionChipView(AssistantViewDelegate* delegate,
-                                       const AssistantSuggestion& suggestion,
-                                       views::ButtonListener* listener)
-    : Button(listener), delegate_(delegate), suggestion_id_(suggestion.id) {
+                                       const AssistantSuggestion& suggestion)
+    : delegate_(delegate), suggestion_id_(suggestion.id) {
   InitLayout(suggestion);
 }
 
 SuggestionChipView::~SuggestionChipView() = default;
 
-const char* SuggestionChipView::GetClassName() const {
-  return kClassName;
-}
-
 gfx::Size SuggestionChipView::CalculatePreferredSize() const {
   const int preferred_width = views::View::CalculatePreferredSize().width();
   return gfx::Size(preferred_width, GetHeightForWidth(preferred_width));
@@ -189,4 +182,7 @@ const base::string16& SuggestionChipView::GetText() const {
   return text_view_->GetText();
 }
 
+BEGIN_METADATA(SuggestionChipView, views::Button)
+END_METADATA
+
 }  // namespace ash

ash/assistant/ui/main_stage/suggestion_chip_view.h

@@ -9,6 +9,7 @@
 #include "base/macros.h"
 #include "chromeos/services/assistant/public/cpp/assistant_service.h"
 #include "ui/views/controls/button/button.h"
+#include "ui/views/metadata/metadata_header_macros.h"
 
 namespace views {
 class BoxLayout;
@@ -25,15 +26,15 @@ class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionChipView : public views::Button {
  public:
   using AssistantSuggestion = chromeos::assistant::AssistantSuggestion;
 
-  static constexpr char kClassName[] = "SuggestionChipView";
+  METADATA_HEADER(SuggestionChipView);
 
   SuggestionChipView(AssistantViewDelegate* delegate,
-                     const AssistantSuggestion& suggestion,
-                     views::ButtonListener* listener);
+                     const AssistantSuggestion& suggestion);
+  SuggestionChipView(const SuggestionChipView&) = delete;
+  SuggestionChipView& operator=(const SuggestionChipView&) = delete;
   ~SuggestionChipView() override;
 
   // views::View:
-  const char* GetClassName() const override;
   gfx::Size CalculatePreferredSize() const override;
   int GetHeightForWidth(int width) const override;
   void ChildVisibilityChanged(views::View* child) override;
@@ -62,8 +63,6 @@ class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionChipView : public views::Button {
   views::Label* text_view_;           // Owned by view hierarchy.
 
   base::WeakPtrFactory<SuggestionChipView> weak_factory_{this};
-
-  DISALLOW_COPY_AND_ASSIGN(SuggestionChipView);
 };
 
 }  // namespace ash

ash/assistant/ui/main_stage/suggestion_chip_view_unittest.cc

@@ -38,8 +38,7 @@ TEST_F(SuggestionChipViewTest, ShouldHandleLocalIcons) {
   SuggestionChipView suggestion_chip_view(
       /*delegate=*/nullptr,
       CreateSuggestionWithIconUrl(
-          "googleassistant://resource?type=icon&name=assistant"),
-      /*listener=*/nullptr);
+          "googleassistant://resource?type=icon&name=assistant"));
 
   const auto& actual = suggestion_chip_view.GetIcon();
   gfx::ImageSkia expected = gfx::CreateVectorIcon(
@@ -62,8 +61,7 @@ TEST_F(SuggestionChipViewTest, ShouldHandleRemoteIcons) {
   SuggestionChipView suggestion_chip_view(
       &delegate,
       CreateSuggestionWithIconUrl("https://www.gstatic.com/images/branding/"
-                                  "product/2x/googleg_48dp.png"),
-      /*listener=*/nullptr);
+                                  "product/2x/googleg_48dp.png"));
 
   const auto& actual = suggestion_chip_view.GetIcon();
   EXPECT_TRUE(actual.BackedBySameObjectAs(expected));

ash/assistant/ui/main_stage/suggestion_container_view.cc

@@ -26,6 +26,7 @@
 #include "ui/compositor/callback_layer_animation_observer.h"
 #include "ui/compositor/layer_animation_element.h"
 #include "ui/views/layout/box_layout.h"
+#include "ui/views/metadata/metadata_impl_macros.h"
 
 namespace ash {
 
@@ -115,10 +116,6 @@ SuggestionContainerView::~SuggestionContainerView() {
     AssistantSuggestionsController::Get()->GetModel()->RemoveObserver(this);
 }
 
-const char* SuggestionContainerView::GetClassName() const {
-  return "SuggestionContainerView";
-}
-
 gfx::Size SuggestionContainerView::CalculatePreferredSize() const {
   return gfx::Size(INT_MAX, GetHeightForWidth(INT_MAX));
 }
@@ -201,8 +198,11 @@ void SuggestionContainerView::OnAllViewsRemoved() {
 
 std::unique_ptr<ElementAnimator> SuggestionContainerView::AddSuggestionChip(
     const AssistantSuggestion& suggestion) {
-  auto suggestion_chip_view = std::make_unique<SuggestionChipView>(
-      delegate(), suggestion, /*listener=*/this);
+  auto suggestion_chip_view =
+      std::make_unique<SuggestionChipView>(delegate(), suggestion);
+  suggestion_chip_view->set_callback(base::BindRepeating(
+      &SuggestionContainerView::OnButtonPressed, base::Unretained(this),
+      base::Unretained(suggestion_chip_view.get())));
 
   // The chip will be animated on its own layer.
   suggestion_chip_view->SetPaintToLayer();
@@ -214,13 +214,6 @@ std::unique_ptr<ElementAnimator> SuggestionContainerView::AddSuggestionChip(
       contents()->AddChildView(std::move(suggestion_chip_view)), this);
 }
 
-void SuggestionContainerView::ButtonPressed(views::Button* sender,
-                                            const ui::Event& event) {
-  // Remember which chip was selected, so we can give it a special animation.
-  selected_chip_ = static_cast<SuggestionChipView*>(sender);
-  delegate()->OnSuggestionPressed(selected_chip_->suggestion_id());
-}
-
 void SuggestionContainerView::OnUiVisibilityChanged(
     AssistantVisibility new_visibility,
     AssistantVisibility old_visibility,
@@ -248,4 +241,13 @@ void SuggestionContainerView::OnUiVisibilityChanged(
       views::BoxLayout::MainAxisAlignment::kCenter);
 }
 
+void SuggestionContainerView::OnButtonPressed(SuggestionChipView* chip_view) {
+  // Remember which chip was selected, so we can give it a special animation.
+  selected_chip_ = chip_view;
+  delegate()->OnSuggestionPressed(selected_chip_->suggestion_id());
+}
+
+BEGIN_METADATA(SuggestionContainerView, AnimatedContainerView)
+END_METADATA
+
 }  // namespace ash

ash/assistant/ui/main_stage/suggestion_container_view.h

@@ -18,6 +18,7 @@
 #include "base/scoped_observer.h"
 #include "chromeos/services/assistant/public/cpp/assistant_service.h"
 #include "ui/views/controls/scroll_view.h"
+#include "ui/views/metadata/metadata_header_macros.h"
 
 namespace views {
 class BoxLayout;
@@ -33,16 +34,18 @@ class AssistantViewDelegate;
 class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionContainerView
     : public AnimatedContainerView,
       public AssistantSuggestionsModelObserver,
-      public AssistantUiModelObserver,
-      public views::ButtonListener {
+      public AssistantUiModelObserver {
  public:
   using AssistantSuggestion = chromeos::assistant::AssistantSuggestion;
 
+  METADATA_HEADER(SuggestionContainerView);
+
   explicit SuggestionContainerView(AssistantViewDelegate* delegate);
+  SuggestionContainerView(const SuggestionContainerView&) = delete;
+  SuggestionContainerView& operator=(const SuggestionContainerView&) = delete;
   ~SuggestionContainerView() override;
 
   // AnimatedContainerView:
-  const char* GetClassName() const override;
   gfx::Size CalculatePreferredSize() const override;
   int GetHeightForWidth(int width) const override;
   void OnContentsPreferredSizeChanged(views::View* content_view) override;
@@ -60,9 +63,6 @@ class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionContainerView
       base::Optional<AssistantEntryPoint> entry_point,
       base::Optional<AssistantExitPoint> exit_point) override;
 
-  // views::ButtonListener:
-  void ButtonPressed(views::Button* sender, const ui::Event& event) override;
-
   // The suggestion chip that was pressed by the user. May be |nullptr|.
   const SuggestionChipView* selected_chip() const { return selected_chip_; }
 
@@ -77,6 +77,8 @@ class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionContainerView
   std::unique_ptr<ElementAnimator> AddSuggestionChip(
       const AssistantSuggestion& suggestion);
 
+  void OnButtonPressed(SuggestionChipView* chip_view);
+
   views::BoxLayout* layout_manager_;  // Owned by view hierarchy.
 
   // Whether or not we have committed a query during this Assistant session.
@@ -84,8 +86,6 @@ class COMPONENT_EXPORT(ASSISTANT_UI) SuggestionContainerView
 
   // The suggestion chip that was pressed by the user. May be |nullptr|.
   const SuggestionChipView* selected_chip_ = nullptr;
-
-  DISALLOW_COPY_AND_ASSIGN(SuggestionContainerView);
 };
 
 }  // namespace ash