ui/app_list/views/image_shadow_animator.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_APP_LIST_VIEWS_IMAGE_SHADOW_ANIMATOR_H_
   6 #define UI_APP_LIST_VIEWS_IMAGE_SHADOW_ANIMATOR_H_
   7
   8 #include "ui/app_list/app_list_export.h"
   9 #include "ui/gfx/animation/animation_delegate.h"
  10 #include "ui/gfx/animation/slide_animation.h"
  11 #include "ui/gfx/image/image_skia.h"
  12 #include "ui/gfx/shadow_value.h"
  13
  14 namespace app_list {
  15
  16 namespace test {
  17 class ImageShadowAnimatorTest;
  18 }  // namespace test
  19
  20 // A helper class that animates an image's shadow between two shadow values.
  21 class APP_LIST_EXPORT ImageShadowAnimator : public gfx::AnimationDelegate {
  22  public:
  23   class Delegate {
  24    public:
  25     // Called when |shadow_image_| is updated.
  26     virtual void ImageShadowAnimationProgressed(
  27         ImageShadowAnimator* animator) = 0;
  28   };
  29
  30   explicit ImageShadowAnimator(Delegate* delegate);
  31   ~ImageShadowAnimator() override;
  32
  33   // Sets the image that will have its shadow animated. Synchronously calls the
  34   // Delegate's ImageShadowAnimationProgressed() method.
  35   void SetOriginalImage(const gfx::ImageSkia& image);
  36
  37   // Sets the shadow values to animate between.
  38   void SetStartAndEndShadows(const gfx::ShadowValues& start_shadow,
  39                              const gfx::ShadowValues& end_shadow);
  40
  41   gfx::SlideAnimation* animation() { return &animation_; }
  42
  43   const gfx::ImageSkia& shadow_image() const { return shadow_image_; }
  44
  45   // Overridden from gfx::AnimationDelegate:
  46   void AnimationProgressed(const gfx::Animation* animation) override;
  47
  48  private:
  49   friend test::ImageShadowAnimatorTest;
  50
  51   // Returns shadow values for a tween between |start_shadow_| and |end_shadow_|
  52   // at |progress|.
  53   gfx::ShadowValues GetShadowValuesForProgress(double progress) const;
  54
  55   // Updates |shadow_image_| and notifies the delegate.
  56   void UpdateShadowImageForProgress(double progress);
  57
  58   Delegate* const delegate_;
  59
  60   // The image to paint a drop shadow for.
  61   gfx::ImageSkia original_image_;
  62
  63   // The image with a drop shadow painted. This stays current with the progress
  64   // of |animation_|.
  65   gfx::ImageSkia shadow_image_;
  66
  67   // The animation that controls the progress of the shadow tween.
  68   gfx::SlideAnimation animation_;
  69
  70   // The shadow value to tween from.
  71   gfx::ShadowValues start_shadow_;
  72
  73   // The shadow value to tween to.
  74   gfx::ShadowValues end_shadow_;
  75
  76   DISALLOW_COPY_AND_ASSIGN(ImageShadowAnimator);
  77 };
  78
  79 }  // namespace app_list
  80
  81 #endif  // UI_APP_LIST_VIEWS_IMAGE_SHADOW_ANIMATOR_H_