1// Copyright 2013 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#include "ash/frame/caption_buttons/frame_caption_button.h"
6
7#include "ui/base/resource/resource_bundle.h"
8#include "ui/gfx/animation/slide_animation.h"
9#include "ui/gfx/animation/throb_animation.h"
10#include "ui/gfx/canvas.h"
11
12namespace ash {
13
14namespace {
15
16// The duration of the crossfade animation when swapping the button's images.
17const int kSwapImagesAnimationDurationMs = 200;
18
19// The duration of the fade out animation of the old icon during a crossfade
20// animation as a ratio of |kSwapImagesAnimationDurationMs|.
21const float kFadeOutRatio = 0.5f;
22
23}  // namespace
24
25// static
26const char FrameCaptionButton::kViewClassName[] = "FrameCaptionButton";
27
28FrameCaptionButton::FrameCaptionButton(views::ButtonListener* listener,
29                                       CaptionButtonIcon icon)
30    : CustomButton(listener),
31      icon_(icon),
32      paint_as_active_(false),
33      icon_image_id_(-1),
34      inactive_icon_image_id_(-1),
35      hovered_background_image_id_(-1),
36      pressed_background_image_id_(-1),
37      swap_images_animation_(new gfx::SlideAnimation(this)) {
38  swap_images_animation_->Reset(1);
39
40  // Do not flip the gfx::Canvas passed to the OnPaint() method. The snap left
41  // and snap right button icons should not be flipped. The other icons are
42  // horizontally symmetrical.
43}
44
45FrameCaptionButton::~FrameCaptionButton() {
46}
47
48void FrameCaptionButton::SetImages(CaptionButtonIcon icon,
49                                   Animate animate,
50                                   int icon_image_id,
51                                   int inactive_icon_image_id,
52                                   int hovered_background_image_id,
53                                   int pressed_background_image_id) {
54  // The early return is dependant on |animate| because callers use SetImages()
55  // with ANIMATE_NO to progress the crossfade animation to the end.
56  if (icon == icon_ &&
57      (animate == ANIMATE_YES || !swap_images_animation_->is_animating()) &&
58      icon_image_id == icon_image_id_ &&
59      inactive_icon_image_id == inactive_icon_image_id_ &&
60      hovered_background_image_id == hovered_background_image_id_ &&
61      pressed_background_image_id == pressed_background_image_id_) {
62    return;
63  }
64
65  if (animate == ANIMATE_YES)
66    crossfade_icon_image_ = GetIconImageToPaint();
67
68  icon_ = icon;
69  icon_image_id_ = icon_image_id;
70  inactive_icon_image_id_ = inactive_icon_image_id;
71  hovered_background_image_id_ = hovered_background_image_id;
72  pressed_background_image_id_ = pressed_background_image_id;
73
74  ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
75  icon_image_ = *rb.GetImageSkiaNamed(icon_image_id);
76  inactive_icon_image_ = *rb.GetImageSkiaNamed(inactive_icon_image_id);
77  hovered_background_image_ = *rb.GetImageSkiaNamed(
78      hovered_background_image_id);
79  pressed_background_image_ = *rb.GetImageSkiaNamed(
80      pressed_background_image_id);
81
82  if (animate == ANIMATE_YES) {
83    swap_images_animation_->Reset(0);
84    swap_images_animation_->SetSlideDuration(kSwapImagesAnimationDurationMs);
85    swap_images_animation_->Show();
86  } else {
87    swap_images_animation_->Reset(1);
88  }
89  PreferredSizeChanged();
90  SchedulePaint();
91}
92
93bool FrameCaptionButton::IsAnimatingImageSwap() const {
94  return swap_images_animation_->is_animating();
95}
96
97gfx::Size FrameCaptionButton::GetPreferredSize() const {
98  return hovered_background_image_.isNull() ?
99      gfx::Size() : hovered_background_image_.size();
100}
101
102const char* FrameCaptionButton::GetClassName() const {
103  return kViewClassName;
104}
105
106void FrameCaptionButton::OnPaint(gfx::Canvas* canvas) {
107  if (hover_animation_->is_animating() || state() == STATE_HOVERED) {
108    int hovered_background_alpha = hover_animation_->is_animating() ?
109        hover_animation_->CurrentValueBetween(0, 255) : 255;
110    SkPaint paint;
111    paint.setAlpha(hovered_background_alpha);
112    canvas->DrawImageInt(hovered_background_image_, 0, 0, paint);
113  } else if (state() == STATE_PRESSED) {
114    canvas->DrawImageInt(pressed_background_image_, 0, 0);
115  }
116
117  int icon_alpha = swap_images_animation_->CurrentValueBetween(0, 255);
118  int crossfade_icon_alpha = 0;
119  if (icon_alpha < static_cast<int>(kFadeOutRatio * 255))
120     crossfade_icon_alpha = static_cast<int>(255 - icon_alpha / kFadeOutRatio);
121
122  gfx::ImageSkia icon_image = GetIconImageToPaint();
123  if (crossfade_icon_alpha > 0 && !crossfade_icon_image_.isNull()) {
124    gfx::Canvas icon_canvas(icon_image.size(), canvas->image_scale(), false);
125    SkPaint paint;
126    paint.setAlpha(icon_alpha);
127    icon_canvas.DrawImageInt(icon_image, 0, 0, paint);
128
129    paint.setAlpha(crossfade_icon_alpha);
130    paint.setXfermodeMode(SkXfermode::kPlus_Mode);
131    icon_canvas.DrawImageInt(crossfade_icon_image_, 0, 0, paint);
132
133    PaintCentered(canvas, gfx::ImageSkia(icon_canvas.ExtractImageRep()), 255);
134  } else {
135    PaintCentered(canvas, icon_image, icon_alpha);
136  }
137}
138
139void FrameCaptionButton::OnGestureEvent(ui::GestureEvent* event) {
140  // CustomButton does not become pressed when the user drags off and then back
141  // onto the button. Make FrameCaptionButton pressed in this case because this
142  // behavior is more consistent with AlternateFrameSizeButton.
143  if (event->type() == ui::ET_GESTURE_SCROLL_BEGIN ||
144      event->type() == ui::ET_GESTURE_SCROLL_UPDATE) {
145    if (HitTestPoint(event->location())) {
146      SetState(STATE_PRESSED);
147      RequestFocus();
148      event->StopPropagation();
149    } else {
150      SetState(STATE_NORMAL);
151    }
152  } else if (event->type() == ui::ET_GESTURE_SCROLL_END) {
153    if (HitTestPoint(event->location())) {
154      SetState(STATE_HOVERED);
155      NotifyClick(*event);
156      event->StopPropagation();
157    }
158  }
159  CustomButton::OnGestureEvent(event);
160}
161
162const gfx::ImageSkia& FrameCaptionButton::GetIconImageToPaint() const {
163  return paint_as_active_ ? icon_image_ : inactive_icon_image_;
164}
165
166void FrameCaptionButton::PaintCentered(gfx::Canvas* canvas,
167                                       const gfx::ImageSkia& to_center,
168                                       int alpha) {
169  SkPaint paint;
170  paint.setAlpha(alpha);
171  canvas->DrawImageInt(to_center,
172                       (width() - to_center.width()) / 2,
173                       (height() - to_center.height()) / 2,
174                       paint);
175}
176
177}  // namespace ash
178