Extract the view of control buttons on notification into a separated class

ui/message_center/views/notification_control_buttons_view.cc

+// 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 "ui/message_center/views/notification_control_buttons_view.h"
+
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/compositor/layer.h"
+#include "ui/events/event.h"
+#include "ui/gfx/animation/linear_animation.h"
+#include "ui/message_center/message_center_style.h"
+#include "ui/message_center/views/message_view.h"
+#include "ui/message_center/views/padded_button.h"
+#include "ui/strings/grit/ui_strings.h"
+#include "ui/views/background.h"
+#include "ui/views/layout/box_layout.h"
+
+namespace {
+
+// This value should be the same as the duration of reveal animation of
+// the settings view of an Android notification.
+constexpr int kBackgroundColorChangeDuration = 360;
+
+// The initial background color of the view.
+constexpr SkColor kInitialBackgroundColor =
+    message_center::kControlButtonBackgroundColor;
+
+}  // anonymous namespace
+
+namespace message_center {
+
+const char NotificationControlButtonsView::kViewClassName[] =
+    "NotificationControlButtonsView";
+
+NotificationControlButtonsView::NotificationControlButtonsView(
+    MessageView* message_view)
+    : message_view_(message_view),
+      bgcolor_origin_(kInitialBackgroundColor),
+      bgcolor_target_(kInitialBackgroundColor) {
+  DCHECK(message_view);
+  SetLayoutManager(new views::BoxLayout(views::BoxLayout::kHorizontal));
+  SetBackground(views::CreateSolidBackground(kInitialBackgroundColor));
+}
+
+NotificationControlButtonsView::~NotificationControlButtonsView() = default;
+
+void NotificationControlButtonsView::ShowCloseButton(bool show) {

[yhanada, 2017/06/29 04:14:47]

What will happen if the notification is pinned then unpinned then pinned? Can
the order of the buttons change?

[yoshiki, 2017/06/29 06:29:42]

Good catch. I fixed the issue.

+  if (show && !close_button_) {
+    close_button_ = new message_center::PaddedButton(this);
+    close_button_->SetImage(views::CustomButton::STATE_NORMAL,
+                            message_center::GetCloseIcon());
+    close_button_->SetAccessibleName(l10n_util::GetStringUTF16(
+        IDS_MESSAGE_CENTER_CLOSE_NOTIFICATION_BUTTON_ACCESSIBLE_NAME));
+    close_button_->SetTooltipText(l10n_util::GetStringUTF16(
+        IDS_MESSAGE_CENTER_CLOSE_NOTIFICATION_BUTTON_TOOLTIP));
+    close_button_->SetBackground(
+        views::CreateSolidBackground(SK_ColorTRANSPARENT));
+    AddChildView(close_button_);
+  } else if (!show && close_button_) {
+    RemoveChildView(close_button_);
+    close_button_ = nullptr;
+  }
+}
+
+void NotificationControlButtonsView::ShowSettingsButton(bool show) {
+  if (show && !settings_button_) {
+    settings_button_ = new message_center::PaddedButton(this);
+    settings_button_->SetImage(views::CustomButton::STATE_NORMAL,
+                               message_center::GetSettingsIcon());
+    settings_button_->SetAccessibleName(l10n_util::GetStringUTF16(
+        IDS_MESSAGE_NOTIFICATION_SETTINGS_BUTTON_ACCESSIBLE_NAME));
+    settings_button_->SetTooltipText(l10n_util::GetStringUTF16(
+        IDS_MESSAGE_NOTIFICATION_SETTINGS_BUTTON_ACCESSIBLE_NAME));
+    settings_button_->SetBackground(
+        views::CreateSolidBackground(SK_ColorTRANSPARENT));
+    AddChildView(settings_button_);
+  } else if (!show && close_button_) {
+    RemoveChildView(settings_button_);
+    settings_button_ = nullptr;
+  }
+}
+
+void NotificationControlButtonsView::SetBackgroundColor(
+    const SkColor& target_bgcolor) {
+  if (background()->get_color() != target_bgcolor) {
+    bgcolor_origin_ = background()->get_color();
+    bgcolor_target_ = target_bgcolor;
+
+    if (bgcolor_animation_)
+      bgcolor_animation_->End();
+    bgcolor_animation_.reset(new gfx::LinearAnimation(this));
+    bgcolor_animation_->SetDuration(kBackgroundColorChangeDuration);
+    bgcolor_animation_->Start();
+  }
+}
+
+void NotificationControlButtonsView::RequestFocusOnCloseButton() {
+  if (close_button_)
+    close_button_->RequestFocus();
+}
+
+bool NotificationControlButtonsView::IsCloseButtonFocused() const {
+  return close_button_ && close_button_->HasFocus();
+}
+
+bool NotificationControlButtonsView::IsSettingsButtonFocused() const {
+  return settings_button_ && settings_button_->HasFocus();
+}
+
+const char* NotificationControlButtonsView::GetClassName() const {
+  return kViewClassName;
+}
+
+void NotificationControlButtonsView::ButtonPressed(views::Button* sender,
+                                                   const ui::Event& event) {
+  if (close_button_ && sender == close_button_) {
+    message_view_->OnCloseButtonPressed();
+  } else if (settings_button_ && sender == settings_button_) {
+    message_view_->OnSettingsButtonPressed();
+  }
+}
+
+void NotificationControlButtonsView::AnimationProgressed(
+    const gfx::Animation* animation) {
+  DCHECK_EQ(animation, bgcolor_animation_.get());
+
+  const SkColor color = gfx::Tween::ColorValueBetween(
+      animation->GetCurrentValue(), bgcolor_origin_, bgcolor_target_);
+  SetBackground(views::CreateSolidBackground(color));
+  SchedulePaint();
+}
+
+void NotificationControlButtonsView::AnimationEnded(
+    const gfx::Animation* animation) {
+  DCHECK_EQ(animation, bgcolor_animation_.get());
+  bgcolor_animation_.reset();
+  bgcolor_origin_ = bgcolor_target_;
+}
+
+void NotificationControlButtonsView::AnimationCanceled(
+    const gfx::Animation* animation) {
+  // The animation is never cancelled explicitly.
+  NOTREACHED();
+
+  bgcolor_origin_ = bgcolor_target_;
+  SetBackground(views::CreateSolidBackground(bgcolor_target_));
+  SchedulePaint();
+}
+
+}  // namespace message_center