ui/views/controls/scrollbar/kennedy_scroll_bar.cc

   1 // Copyright (c) 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 "ui/views/controls/scrollbar/kennedy_scroll_bar.h"
   6
   7 #include "third_party/skia/include/core/SkColor.h"
   8 #include "third_party/skia/include/core/SkXfermode.h"
   9 #include "ui/gfx/canvas.h"
  10 #include "ui/views/background.h"
  11 #include "ui/views/border.h"
  12 #include "ui/views/controls/scrollbar/base_scroll_bar_thumb.h"
  13
  14 namespace views {
  15 namespace {
  16
  17 const int kScrollbarWidth = 10;
  18 const int kThumbMinimumSize = kScrollbarWidth * 2;
  19 const SkColor kBorderColor = SkColorSetARGB(32, 0, 0, 0);
  20 const SkColor kThumbHoverColor = SkColorSetARGB(128, 0, 0, 0);
  21 const SkColor kThumbDefaultColor = SkColorSetARGB(64, 0, 0, 0);
  22 const SkColor kTrackHoverColor = SkColorSetARGB(32, 0, 0, 0);
  23
  24 class KennedyScrollBarThumb : public BaseScrollBarThumb {
  25  public:
  26   explicit KennedyScrollBarThumb(BaseScrollBar* scroll_bar);
  27   ~KennedyScrollBarThumb() override;
  28
  29  protected:
  30   // View overrides:
  31   gfx::Size GetPreferredSize() const override;
  32   void OnPaint(gfx::Canvas* canvas) override;
  33
  34  private:
  35   DISALLOW_COPY_AND_ASSIGN(KennedyScrollBarThumb);
  36 };
  37
  38 KennedyScrollBarThumb::KennedyScrollBarThumb(BaseScrollBar* scroll_bar)
  39     : BaseScrollBarThumb(scroll_bar) {
  40 }
  41
  42 KennedyScrollBarThumb::~KennedyScrollBarThumb() {
  43 }
  44
  45 gfx::Size KennedyScrollBarThumb::GetPreferredSize() const {
  46   return gfx::Size(kThumbMinimumSize, kThumbMinimumSize);
  47 }
  48
  49 void KennedyScrollBarThumb::OnPaint(gfx::Canvas* canvas) {
  50   gfx::Rect local_bounds(GetLocalBounds());
  51   canvas->FillRect(local_bounds,
  52                    (GetState() == CustomButton::STATE_HOVERED ||
  53                     GetState() == CustomButton::STATE_PRESSED) ?
  54                    kThumbHoverColor : kThumbDefaultColor);
  55   canvas->DrawRect(local_bounds, kBorderColor);
  56 }
  57
  58 }  // namespace
  59
  60 KennedyScrollBar::KennedyScrollBar(bool horizontal)
  61     : BaseScrollBar(horizontal, new KennedyScrollBarThumb(this)) {
  62   set_notify_enter_exit_on_child(true);
  63 }
  64
  65 KennedyScrollBar::~KennedyScrollBar() {
  66 }
  67
  68 gfx::Rect KennedyScrollBar::GetTrackBounds() const {
  69   gfx::Rect local_bounds(GetLocalBounds());
  70   gfx::Size track_size = local_bounds.size();
  71   track_size.SetToMax(GetThumb()->size());
  72   local_bounds.set_size(track_size);
  73   return local_bounds;
  74 }
  75
  76 int KennedyScrollBar::GetLayoutSize() const {
  77   return kScrollbarWidth;
  78 }
  79
  80 gfx::Size KennedyScrollBar::GetPreferredSize() const {
  81   return GetTrackBounds().size();
  82 }
  83
  84 void KennedyScrollBar::Layout() {
  85   gfx::Rect thumb_bounds = GetTrackBounds();
  86   BaseScrollBarThumb* thumb = GetThumb();
  87   if (IsHorizontal()) {
  88     thumb_bounds.set_x(thumb->x());
  89     thumb_bounds.set_width(thumb->width());
  90   } else {
  91     thumb_bounds.set_y(thumb->y());
  92     thumb_bounds.set_height(thumb->height());
  93   }
  94   thumb->SetBoundsRect(thumb_bounds);
  95 }
  96
  97 void KennedyScrollBar::OnPaint(gfx::Canvas* canvas) {
  98   CustomButton::ButtonState state = GetThumbTrackState();
  99   if ((state == CustomButton::STATE_HOVERED) ||
 100       (state == CustomButton::STATE_PRESSED)) {
 101     gfx::Rect local_bounds(GetLocalBounds());
 102     canvas->FillRect(local_bounds, kTrackHoverColor);
 103     canvas->DrawRect(local_bounds, kBorderColor);
 104   }
 105 }
 106
 107 }  // namespace views