Add ripple effect to new-style notification header.

ui/message_center/views/notification_header_view.cc

Index: ui/message_center/views/notification_header_view.cc
diff --git a/ui/message_center/views/notification_header_view.cc b/ui/message_center/views/notification_header_view.cc
index 97cdd3615e5f54a81311eeb736c30e2a68671d70..e469f8694772c1811dab86865915e0a184292894 100644
--- a/ui/message_center/views/notification_header_view.cc
+++ b/ui/message_center/views/notification_header_view.cc
@@ -12,6 +12,9 @@
 #include "ui/message_center/vector_icons.h"
 #include "ui/message_center/views/padded_button.h"
 #include "ui/strings/grit/ui_strings.h"
+#include "ui/views/animation/flood_fill_ink_drop_ripple.h"
+#include "ui/views/animation/ink_drop_highlight.h"
+#include "ui/views/animation/ink_drop_impl.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
@@ -29,10 +32,25 @@ constexpr gfx::Insets kHeaderPadding(0, 12, 0, 2);
 constexpr int kHeaderHorizontalSpacing = 2;
 constexpr int kAppInfoConatainerTopPadding = 12;
 
+// Base ink drop color of action buttons.
+const SkColor kInkDropBaseColor = SkColorSetRGB(0x0, 0x0, 0x0);
+// Ripple ink drop opacity of action buttons.
+const float kInkDropRippleVisibleOpacity = 0.08f;
+// Highlight (hover) ink drop opacity of action buttons.
+const float kInkDropHighlightVisibleOpacity = 0.08f;
+
 }  // namespace
 
 NotificationHeaderView::NotificationHeaderView(views::ButtonListener* listener)
     : views::CustomButton(listener) {
+  SetFocusBehavior(FocusBehavior::ALWAYS);
+  SetInkDropMode(InkDropMode::ON);
+  set_has_ink_drop_action_on_click(true);
+  set_animate_on_state_change(true);
+  set_notify_enter_exit_on_child(true);
+  set_ink_drop_base_color(kInkDropBaseColor);
+  set_ink_drop_visible_opacity(kInkDropRippleVisibleOpacity);
+
   views::BoxLayout* layout = new views::BoxLayout(
       views::BoxLayout::kHorizontal, kHeaderPadding, kHeaderHorizontalSpacing);
   layout->set_cross_axis_alignment(
@@ -151,6 +169,32 @@ bool NotificationHeaderView::IsCloseButtonEnabled() {
   return close_button_enabled_;
 }
 
+std::unique_ptr<views::InkDrop> NotificationHeaderView::CreateInkDrop() {
+  return InkDropHostView::CreateDefaultFloodFillInkDropImpl();
+}
+
+std::unique_ptr<views::InkDropRipple>
+NotificationHeaderView::CreateInkDropRipple() const {
+  return base::MakeUnique<views::FloodFillInkDropRipple>(
+      size(), GetInkDropCenterBasedOnLastEvent(), GetInkDropBaseColor(),
+      ink_drop_visible_opacity());
+}
+
+std::unique_ptr<views::InkDropHighlight>
+NotificationHeaderView::CreateInkDropHighlight() const {
+  std::unique_ptr<views::InkDropHighlight> highlight =
+      base::MakeUnique<views::InkDropHighlight>(
+          size(), kInkDropSmallCornerRadius,
+          gfx::RectF(GetLocalBounds()).CenterPoint(), GetInkDropBaseColor());
+  highlight->set_visible_opacity(kInkDropHighlightVisibleOpacity);
+  return highlight;
+}
+
+void NotificationHeaderView::OnMouseEvent(ui::MouseEvent* event) {
+  // Prevent updating SetHovered in InkDropHostView.
+  View::OnMouseEvent(event);

[fukino, 2017/06/29 04:30:42]

This looks hacky (and scary)...
In ash system menu (which uses HoverHighlightView), there is no color change on
hover.
Could you check how it works?

[tetsui, 2017/06/29 07:49:14]

Done.

+}
+
 void NotificationHeaderView::UpdateControlButtonsVisibility() {
   settings_button_->SetVisible(settings_button_enabled_ &&
                                is_control_buttons_visible_);