[Mac] App Menu Animated Icon

chrome/browser/ui/cocoa/toolbar/app_toolbar_button_icon.h

+// 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.
+
+#ifndef CHROME_BROWSER_UI_COCOA_TOOLBAR_APP_TOOLBAR_BUTTON_ICON_H_
+#define CHROME_BROWSER_UI_COCOA_TOOLBAR_APP_TOOLBAR_BUTTON_ICON_H_
+
+#import <Cocoa/Cocoa.h>
+
+#include <memory>
+
+#include "base/mac/scoped_nsobject.h"
+#include "base/time/time.h"
+#include "third_party/skia/include/core/SkColor.h"
+#include "ui/gfx/animation/animation_delegate.h"
+
+namespace gfx {
+class SlideAnimation;
+}  // namespace gfx
+
+@class AppToolbarButton;
+
+// This class is used to represent and paint a dot on the app menu.
+class AppMenuDot {
+ public:
+  AppMenuDot(base::TimeDelta delay,
+             float width_open_interval,
+             float stroke_open_interval);
+
+  void DrawDot(NSPoint center_pt,
+               NSSize imageSize,
+               SkColor startColor,
+               SkColor targetColor,
+               const gfx::SlideAnimation* animation);
+
+ private:
+  // The delay before the dot starts animating in ms.
+  const base::TimeDelta delay_;
+
+  // The percentage of the overall animation duration it takes to animate the
+  // width and stroke to their open state.
+  const float width_open_interval_;
+  const float stroke_open_interval_;
+
+  DISALLOW_COPY_AND_ASSIGN(AppMenuDot);
+};
+
+// This class is used for animating and drawing the app menu icon.
+class AppToolbarButtonIcon : public gfx::AnimationDelegate {
+ public:
+  AppToolbarButtonIcon(AppToolbarButton* owner, SkColor start_color);
+
+  ~AppToolbarButtonIcon() override;
+
+  // Draws the App Menu Icon according to the given |frame|.
+  void DrawIcon(NSRect frame);
+
+  // Starts the animation if it's not already running.
+  void StartAnimation();
+
+  // gfx::AnimationDelegate:
+  void AnimationEnded(const gfx::Animation* animation) override;
+  void AnimationProgressed(const gfx::Animation* animation) override;
+
+  void set_target_color(SkColor target_color) { target_color_ = target_color; }
+
+ private:
+  std::unique_ptr<gfx::SlideAnimation> animation_;
+
+  AppMenuDot bottom_dot_;
+  AppMenuDot center_dot_;
+  AppMenuDot top_dot_;
+
+  // The color the icon is animating from/to.
+  SkColor start_color_;
+  SkColor target_color_;
+
+  AppToolbarButton* owner_;  // weak.
+};
+
+#endif  // CHROME_BROWSER_UI_COCOA_TOOLBAR_APP_TOOLBAR_BUTTON_ICON_H_