MenuButtons enter Hover state upon Tap Down

MenuButton will now respond to TAP_DOWN gestures, entering the Hover state. It will return to a normal state if the gesture is cancelled. Tap gestures that activate the menu will still cause it to enter a Pressed state.

This experiment is behind the flag switches::kEnableTouchFeedback

TEST=MenuButtonTest.TouchFeedbackDuringTap, MenuButtonTest.TouchFeedbackDuringTapCancel
BUG=398404

Review URL: https://codereview.chromium.org/674163003

Cr-Commit-Position: refs/heads/master@{#301488}

2 files changed, 56 insertions, 6 deletions

diff --git a/ui/views/controls/button/menu_button.cc b/ui/views/controls/button/menu_button.cc
index f2b3852..aee3930 100644
--- a/ui/views/controls/button/menu_button.cc
+++ b/ui/views/controls/button/menu_button.cc
@@ -9,6 +9,7 @@
 #include "ui/base/dragdrop/drag_drop_types.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/base/ui_base_switches_util.h"
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
 #include "ui/gfx/canvas.h"
@@ -205,12 +206,23 @@ void MenuButton::OnMouseMoved(const ui::MouseEvent& event) {
 }
 
 void MenuButton::OnGestureEvent(ui::GestureEvent* event) {
-  if (state() != STATE_DISABLED && ShouldEnterPushedState(*event) &&
-      !Activate()) {
-    // When |Activate()| returns |false|, it means that a menu is shown and
-    // has handled the gesture event. So, there is no need to further process
-    // the gesture event here.
-    return;
+  if (state() != STATE_DISABLED) {
+    if (ShouldEnterPushedState(*event) && !Activate()) {
+      // When |Activate()| returns |false|, it means that a menu is shown and
+      // has handled the gesture event. So, there is no need to further process
+      // the gesture event here.
+      return;
+    }
+    if (switches::IsTouchFeedbackEnabled()) {
+      if (event->type() == ui::ET_GESTURE_TAP_DOWN) {
+        event->SetHandled();
+        SetState(Button::STATE_HOVERED);
+      } else if (state() == Button::STATE_HOVERED &&
+                 (event->type() == ui::ET_GESTURE_TAP_CANCEL ||
+                  event->type() == ui::ET_GESTURE_END)) {
+        SetState(Button::STATE_NORMAL);
+      }
+    }
   }
   LabelButton::OnGestureEvent(event);
 }
diff --git a/ui/views/controls/button/menu_button_unittest.cc b/ui/views/controls/button/menu_button_unittest.cc
index 21a72a6..a537c1f 100644
--- a/ui/views/controls/button/menu_button_unittest.cc
+++ b/ui/views/controls/button/menu_button_unittest.cc
@@ -4,9 +4,11 @@
 
 #include "ui/views/controls/button/menu_button.h"
 
+#include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
+#include "ui/base/ui_base_switches.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/views/controls/button/menu_button_listener.h"
 #include "ui/views/drag_controller.h"
@@ -27,6 +29,12 @@ class MenuButtonTest : public ViewsTestBase {
   MenuButtonTest() : widget_(nullptr), button_(nullptr) {}
   ~MenuButtonTest() override {}
 
+  void SetUp() override {
+    CommandLine::ForCurrentProcess()->AppendSwitch(
+        switches::kEnableTouchFeedback);
+    ViewsTestBase::SetUp();
+  }
+
   void TearDown() override {
     if (widget_ && !widget_->IsClosed())
       widget_->Close();
@@ -390,4 +398,34 @@ TEST_F(MenuButtonTest, DraggableMenuButtonDoesNotActivateOnDrag) {
 }
 #endif
 
+// Tests that the button enters a hovered state upon a tap down, before becoming
+// pressed at activation.
+TEST_F(MenuButtonTest, TouchFeedbackDuringTap) {
+  TestMenuButtonListener menu_button_listener;
+  CreateMenuButtonWithMenuButtonListener(&menu_button_listener);
+  ui::test::EventGenerator generator(GetContext(), widget()->GetNativeWindow());
+  generator.set_current_location(gfx::Point(10, 10));
+  generator.PressTouch();
+  EXPECT_EQ(Button::STATE_HOVERED, button()->state());
+
+  generator.ReleaseTouch();
+  EXPECT_EQ(Button::STATE_PRESSED, menu_button_listener.last_source_state());
+}
+
+// Tests that a move event that exits the button returns it to the normal state,
+// and that the button did not activate the listener.
+TEST_F(MenuButtonTest, TouchFeedbackDuringTapCancel) {
+  TestMenuButtonListener menu_button_listener;
+  CreateMenuButtonWithMenuButtonListener(&menu_button_listener);
+  ui::test::EventGenerator generator(GetContext(), widget()->GetNativeWindow());
+  generator.set_current_location(gfx::Point(10, 10));
+  generator.PressTouch();
+  EXPECT_EQ(Button::STATE_HOVERED, button()->state());
+
+  generator.MoveTouch(gfx::Point(10, 30));
+  generator.ReleaseTouch();
+  EXPECT_EQ(Button::STATE_NORMAL, button()->state());
+  EXPECT_EQ(nullptr, menu_button_listener.last_source());
+}
+
 }  // namespace views