Adding ripple effect for clicks on MD slider

ui/views/controls/slider.cc

 // 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/slider.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 158 matching lines @@
   View::OnPaint(canvas);
   OnPaintFocus(canvas);
 }
 
 float Slider::GetAnimatingValue() const{
   return move_animation_.get() && move_animation_->is_animating()
              ? animating_value_
              : value_;
 }
 
+void Slider::SetHighlighted(bool focus) {
+  return;

[bruthig, 2016/09/22 21:05:24]

nit: Remove

[yiyix, 2016/09/23 20:35:37]

Highlight needs a default implementation, so non_md_slider does not need to
implement this function. I originally have "virtual void SetHighlighted(bool
focus){};" and you asked me to move it to cc file. So does it mean that i should
have it in the .h file?

[bruthig, 2016/09/23 22:24:39]

I was just asking you to remove the return; statement.

+}
+
 bool Slider::OnMousePressed(const ui::MouseEvent& event) {
   if (!event.IsOnlyLeftMouseButton())
     return false;
   OnSliderDragStarted();
   PrepareForMove(event.location().x());
   MoveButtonTo(event.location());
   return true;
 }
 
 bool Slider::OnMouseDragged(const ui::MouseEvent& event) {
@@ skipping 11 matching lines @@
     new_value -= keyboard_increment_;
   else if (event.key_code() == ui::VKEY_RIGHT)
     new_value += keyboard_increment_;
   else
     return false;
   SetValueInternal(new_value, VALUE_CHANGED_BY_USER);
   return true;
 }
 
 void Slider::OnFocus() {
+  SetHighlighted(true);
   View::OnFocus();
   SchedulePaint();
 }
 
 void Slider::OnBlur() {
+  SetHighlighted(false);
   View::OnBlur();
   SchedulePaint();
 }
 
 void Slider::OnGestureEvent(ui::GestureEvent* event) {
   switch (event->type()) {
     // In a multi point gesture only the touch point will generate
     // an ET_GESTURE_TAP_DOWN event.
     case ui::ET_GESTURE_TAP_DOWN:
       OnSliderDragStarted();
       PrepareForMove(event->location().x());
       // Intentional fall through to next case.
     case ui::ET_GESTURE_SCROLL_BEGIN:
     case ui::ET_GESTURE_SCROLL_UPDATE:
       MoveButtonTo(event->location());
       event->SetHandled();
       break;
     case ui::ET_GESTURE_END:
       MoveButtonTo(event->location());
       event->SetHandled();
       if (event->details().touch_points() <= 1)
         OnSliderDragEnded();
       break;
     default:
       break;
   }
 }
 
 void Slider::AnimationProgressed(const gfx::Animation* animation) {
-  animating_value_ = animation->CurrentValueBetween(animating_value_, value_);
-  SchedulePaint();
+  if (move_animation_.get() && (animation == move_animation_.get())) {

[bruthig, 2016/09/22 21:05:24]

nit: Checking that |move_animation_| here is redundant.  I think it's safe to
assume |animation| will never be null.

+    float old_animating_value = animating_value_;
+    animating_value_ = animation->CurrentValueBetween(animating_value_, value_);
+    if (animating_value_ != old_animating_value)
+      SchedulePaint();
+  }
 }
 
 void Slider::GetAccessibleState(ui::AXViewState* state) {
   state->role = ui::AX_ROLE_SLIDER;
   state->name = accessible_name_;
   state->value = base::UTF8ToUTF16(
       base::StringPrintf("%d%%", static_cast<int>(value_ * 100 + 0.5)));
 }
 
 void Slider::OnSliderDragStarted() {
+  SetHighlighted(true);
   if (listener_)
     listener_->SliderDragStarted(this);
 }
 
 void Slider::OnSliderDragEnded() {
+  SetHighlighted(false);
   if (listener_)
     listener_->SliderDragEnded(this);
 }
 
 }  // namespace views