Move controls into their own dir under chrome/views/controls

TBR=sky

Review URL: http://codereview.chromium.org/48058

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@11841 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 703 insertions, 0 deletions

diff --git a/chrome/views/controls/scrollbar/bitmap_scroll_bar.cc b/chrome/views/controls/scrollbar/bitmap_scroll_bar.cc
new file mode 100644
index 0000000..42ba4e7
--- /dev/null
+++ b/chrome/views/controls/scrollbar/bitmap_scroll_bar.cc
@@ -0,0 +1,703 @@
+// Copyright (c) 2006-2008 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 "chrome/views/controls/scrollbar/bitmap_scroll_bar.h"
+
+#include "base/message_loop.h"
+#include "chrome/common/gfx/chrome_canvas.h"
+#include "chrome/common/l10n_util.h"
+#include "chrome/views/controls/menu/menu.h"
+#include "chrome/views/controls/scroll_view.h"
+#include "chrome/views/widget/widget.h"
+#include "grit/generated_resources.h"
+#include "skia/include/SkBitmap.h"
+
+#undef min
+#undef max
+
+namespace views {
+
+namespace {
+
+// The distance the mouse can be dragged outside the bounds of the thumb during
+// dragging before the scrollbar will snap back to its regular position.
+static const int kScrollThumbDragOutSnap = 100;
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// AutorepeatButton
+//
+//  A button that activates on mouse pressed rather than released, and that
+//  continues to fire the clicked action as the mouse button remains pressed
+//  down on the button.
+//
+///////////////////////////////////////////////////////////////////////////////
+class AutorepeatButton : public ImageButton {
+ public:
+  AutorepeatButton(ButtonListener* listener)
+      : ImageButton(listener),
+        repeater_(NewCallback<AutorepeatButton>(this,
+            &AutorepeatButton::NotifyClick)) {
+  }
+  virtual ~AutorepeatButton() {}
+
+ protected:
+  virtual bool OnMousePressed(const MouseEvent& event) {
+    Button::NotifyClick(event.GetFlags());
+    repeater_.Start();
+    return true;
+  }
+
+  virtual void OnMouseReleased(const MouseEvent& event, bool canceled) {
+    repeater_.Stop();
+    View::OnMouseReleased(event, canceled);
+  }
+
+ private:
+  void NotifyClick() {
+    Button::NotifyClick(0);
+  }
+
+  // The repeat controller that we use to repeatedly click the button when the
+  // mouse button is down.
+  RepeatController repeater_;
+
+  DISALLOW_EVIL_CONSTRUCTORS(AutorepeatButton);
+};
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// BitmapScrollBarThumb
+//
+//  A view that acts as the thumb in the scroll bar track that the user can
+//  drag to scroll the associated contents view within the viewport.
+//
+///////////////////////////////////////////////////////////////////////////////
+class BitmapScrollBarThumb : public View {
+ public:
+  explicit BitmapScrollBarThumb(BitmapScrollBar* scroll_bar)
+      : scroll_bar_(scroll_bar),
+        drag_start_position_(-1),
+        mouse_offset_(-1),
+        state_(CustomButton::BS_NORMAL) {
+  }
+  virtual ~BitmapScrollBarThumb() { }
+
+  // Sets the size (width or height) of the thumb to the specified value.
+  void SetSize(int size) {
+    // Make sure the thumb is never sized smaller than its minimum possible
+    // display size.
+    gfx::Size prefsize = GetPreferredSize();
+    size = std::max(size,
+                    static_cast<int>(scroll_bar_->IsHorizontal() ?
+                        prefsize.width() : prefsize.height()));
+    gfx::Rect thumb_bounds = bounds();
+    if (scroll_bar_->IsHorizontal()) {
+      thumb_bounds.set_width(size);
+    } else {
+      thumb_bounds.set_height(size);
+    }
+    SetBounds(thumb_bounds);
+  }
+
+  // Retrieves the size (width or height) of the thumb.
+  int GetSize() const {
+    if (scroll_bar_->IsHorizontal())
+      return width();
+    return height();
+  }
+
+  // Sets the position of the thumb on the x or y axis.
+  void SetPosition(int position) {
+    gfx::Rect thumb_bounds = bounds();
+    gfx::Rect track_bounds = scroll_bar_->GetTrackBounds();
+    if (scroll_bar_->IsHorizontal()) {
+      thumb_bounds.set_x(track_bounds.x() + position);
+    } else {
+      thumb_bounds.set_x(track_bounds.y() + position);
+    }
+    SetBounds(thumb_bounds);
+  }
+
+  // Gets the position of the thumb on the x or y axis.
+  int GetPosition() const {
+    gfx::Rect track_bounds = scroll_bar_->GetTrackBounds();
+    if (scroll_bar_->IsHorizontal())
+      return x() - track_bounds.x();
+    return y() - track_bounds.y();
+  }
+
+  // View overrides:
+  virtual gfx::Size GetPreferredSize() {
+    return gfx::Size(background_bitmap()->width(),
+                     start_cap_bitmap()->height() +
+                         end_cap_bitmap()->height() +
+                         grippy_bitmap()->height());
+  }
+
+ protected:
+  // View overrides:
+  virtual void Paint(ChromeCanvas* canvas) {
+    canvas->DrawBitmapInt(*start_cap_bitmap(), 0, 0);
+    int top_cap_height = start_cap_bitmap()->height();
+    int bottom_cap_height = end_cap_bitmap()->height();
+    int thumb_body_height = height() - top_cap_height - bottom_cap_height;
+    canvas->TileImageInt(*background_bitmap(), 0, top_cap_height,
+                         background_bitmap()->width(), thumb_body_height);
+    canvas->DrawBitmapInt(*end_cap_bitmap(), 0,
+                          height() - bottom_cap_height);
+
+    // Paint the grippy over the track.
+    int grippy_x = (width() - grippy_bitmap()->width()) / 2;
+    int grippy_y = (thumb_body_height - grippy_bitmap()->height()) / 2;
+    canvas->DrawBitmapInt(*grippy_bitmap(), grippy_x, grippy_y);
+  }
+
+  virtual void OnMouseEntered(const MouseEvent& event) {
+    SetState(CustomButton::BS_HOT);
+  }
+
+  virtual void OnMouseExited(const MouseEvent& event) {
+    SetState(CustomButton::BS_NORMAL);
+  }
+
+  virtual bool OnMousePressed(const MouseEvent& event) {
+    mouse_offset_ = scroll_bar_->IsHorizontal() ? event.x() : event.y();
+    drag_start_position_ = GetPosition();
+    SetState(CustomButton::BS_PUSHED);
+    return true;
+  }
+
+  virtual bool OnMouseDragged(const MouseEvent& event) {
+    // If the user moves the mouse more than |kScrollThumbDragOutSnap| outside
+    // the bounds of the thumb, the scrollbar will snap the scroll back to the
+    // point it was at before the drag began.
+    if (scroll_bar_->IsHorizontal()) {
+      if ((event.y() < y() - kScrollThumbDragOutSnap) ||
+          (event.y() > (y() + height() + kScrollThumbDragOutSnap))) {
+        scroll_bar_->ScrollToThumbPosition(drag_start_position_, false);
+        return true;
+      }
+    } else {
+      if ((event.x() < x() - kScrollThumbDragOutSnap) ||
+          (event.x() > (x() + width() + kScrollThumbDragOutSnap))) {
+        scroll_bar_->ScrollToThumbPosition(drag_start_position_, false);
+        return true;
+      }
+    }
+    if (scroll_bar_->IsHorizontal()) {
+      int thumb_x = event.x() - mouse_offset_;
+      scroll_bar_->ScrollToThumbPosition(x() + thumb_x, false);
+    } else {
+      int thumb_y = event.y() - mouse_offset_;
+      scroll_bar_->ScrollToThumbPosition(y() + thumb_y, false);
+    }
+    return true;
+  }
+
+  virtual void OnMouseReleased(const MouseEvent& event,
+                               bool canceled) {
+    SetState(CustomButton::BS_HOT);
+    View::OnMouseReleased(event, canceled);
+  }
+
+ private:
+  // Returns the bitmap rendered at the start of the thumb.
+  SkBitmap* start_cap_bitmap() const {
+    return scroll_bar_->images_[BitmapScrollBar::THUMB_START_CAP][state_];
+  }
+
+  // Returns the bitmap rendered at the end of the thumb.
+  SkBitmap* end_cap_bitmap() const {
+    return scroll_bar_->images_[BitmapScrollBar::THUMB_END_CAP][state_];
+  }
+
+  // Returns the bitmap that is tiled in the background of the thumb between
+  // the start and the end caps.
+  SkBitmap* background_bitmap() const {
+    return scroll_bar_->images_[BitmapScrollBar::THUMB_MIDDLE][state_];
+  }
+
+  // Returns the bitmap that is rendered in the middle of the thumb
+  // transparently over the background bitmap.
+  SkBitmap* grippy_bitmap() const {
+    return scroll_bar_->images_[BitmapScrollBar::THUMB_GRIPPY]
+        [CustomButton::BS_NORMAL];
+  }
+
+  // Update our state and schedule a repaint when the mouse moves over us.
+  void SetState(CustomButton::ButtonState state) {
+    state_ = state;
+    SchedulePaint();
+  }
+
+  // The BitmapScrollBar that owns us.
+  BitmapScrollBar* scroll_bar_;
+
+  int drag_start_position_;
+
+  // The position of the mouse on the scroll axis relative to the top of this
+  // View when the drag started.
+  int mouse_offset_;
+
+  // The current state of the thumb button.
+  CustomButton::ButtonState state_;
+
+  DISALLOW_EVIL_CONSTRUCTORS(BitmapScrollBarThumb);
+};
+
+} // anonymous namespace
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, public:
+
+BitmapScrollBar::BitmapScrollBar(bool horizontal, bool show_scroll_buttons)
+    : contents_size_(0),
+      contents_scroll_offset_(0),
+      prev_button_(new AutorepeatButton(this)),
+      next_button_(new AutorepeatButton(this)),
+      thumb_(new BitmapScrollBarThumb(this)),
+      thumb_track_state_(CustomButton::BS_NORMAL),
+      last_scroll_amount_(SCROLL_NONE),
+      repeater_(NewCallback<BitmapScrollBar>(this,
+          &BitmapScrollBar::TrackClicked)),
+      context_menu_mouse_position_(0),
+      show_scroll_buttons_(show_scroll_buttons),
+      ScrollBar(horizontal) {
+  if (!show_scroll_buttons_) {
+    prev_button_->SetVisible(false);
+    next_button_->SetVisible(false);
+  }
+
+  AddChildView(prev_button_);
+  AddChildView(next_button_);
+  AddChildView(thumb_);
+
+  SetContextMenuController(this);
+  prev_button_->SetContextMenuController(this);
+  next_button_->SetContextMenuController(this);
+  thumb_->SetContextMenuController(this);
+}
+
+gfx::Rect BitmapScrollBar::GetTrackBounds() const {
+  gfx::Size prefsize = prev_button_->GetPreferredSize();
+  if (IsHorizontal()) {
+    if (!show_scroll_buttons_)
+      prefsize.set_width(0);
+    int new_width =
+        std::max(0, static_cast<int>(width() - (prefsize.width() * 2)));
+    gfx::Rect track_bounds(prefsize.width(), 0, new_width, prefsize.height());
+    return track_bounds;
+  }
+  if (!show_scroll_buttons_)
+    prefsize.set_height(0);
+  gfx::Rect track_bounds(0, prefsize.height(), prefsize.width(),
+                         std::max(0, height() - (prefsize.height() * 2)));
+  return track_bounds;
+}
+
+void BitmapScrollBar::SetImage(ScrollBarPart part,
+                               CustomButton::ButtonState state,
+                               SkBitmap* bitmap) {
+  DCHECK(part < PART_COUNT);
+  DCHECK(state < CustomButton::BS_COUNT);
+  switch (part) {
+    case PREV_BUTTON:
+      prev_button_->SetImage(state, bitmap);
+      break;
+    case NEXT_BUTTON:
+      next_button_->SetImage(state, bitmap);
+      break;
+    case THUMB_START_CAP:
+    case THUMB_MIDDLE:
+    case THUMB_END_CAP:
+    case THUMB_GRIPPY:
+    case THUMB_TRACK:
+      images_[part][state] = bitmap;
+      break;
+  }
+}
+
+void BitmapScrollBar::ScrollByAmount(ScrollAmount amount) {
+  ScrollBarController* controller = GetController();
+  int offset = contents_scroll_offset_;
+  switch (amount) {
+    case SCROLL_START:
+      offset = GetMinPosition();
+      break;
+    case SCROLL_END:
+      offset = GetMaxPosition();
+      break;
+    case SCROLL_PREV_LINE:
+      offset -= controller->GetScrollIncrement(this, false, false);
+      offset = std::max(GetMinPosition(), offset);
+      break;
+    case SCROLL_NEXT_LINE:
+      offset += controller->GetScrollIncrement(this, false, true);
+      offset = std::min(GetMaxPosition(), offset);
+      break;
+    case SCROLL_PREV_PAGE:
+      offset -= controller->GetScrollIncrement(this, true, false);
+      offset = std::max(GetMinPosition(), offset);
+      break;
+    case SCROLL_NEXT_PAGE:
+      offset += controller->GetScrollIncrement(this, true, true);
+      offset = std::min(GetMaxPosition(), offset);
+      break;
+  }
+  contents_scroll_offset_ = offset;
+  ScrollContentsToOffset();
+}
+
+void BitmapScrollBar::ScrollToThumbPosition(int thumb_position,
+                                            bool scroll_to_middle) {
+  contents_scroll_offset_ =
+      CalculateContentsOffset(thumb_position, scroll_to_middle);
+  if (contents_scroll_offset_ < GetMinPosition()) {
+    contents_scroll_offset_ = GetMinPosition();
+  } else if (contents_scroll_offset_ > GetMaxPosition()) {
+    contents_scroll_offset_ = GetMaxPosition();
+  }
+  ScrollContentsToOffset();
+  SchedulePaint();
+}
+
+void BitmapScrollBar::ScrollByContentsOffset(int contents_offset) {
+  contents_scroll_offset_ -= contents_offset;
+  if (contents_scroll_offset_ < GetMinPosition()) {
+    contents_scroll_offset_ = GetMinPosition();
+  } else if (contents_scroll_offset_ > GetMaxPosition()) {
+    contents_scroll_offset_ = GetMaxPosition();
+  }
+  ScrollContentsToOffset();
+}
+
+void BitmapScrollBar::TrackClicked() {
+  if (last_scroll_amount_ != SCROLL_NONE)
+    ScrollByAmount(last_scroll_amount_);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, View implementation:
+
+gfx::Size BitmapScrollBar::GetPreferredSize() {
+  // In this case, we're returning the desired width of the scrollbar and its
+  // minimum allowable height.
+  gfx::Size button_prefsize = prev_button_->GetPreferredSize();
+  return gfx::Size(button_prefsize.width(), button_prefsize.height() * 2);
+}
+
+void BitmapScrollBar::Paint(ChromeCanvas* canvas) {
+  // Paint the track.
+  gfx::Rect track_bounds = GetTrackBounds();
+  canvas->TileImageInt(*images_[THUMB_TRACK][thumb_track_state_],
+                       track_bounds.x(), track_bounds.y(),
+                       track_bounds.width(), track_bounds.height());
+}
+
+void BitmapScrollBar::Layout() {
+  // Size and place the two scroll buttons.
+  if (show_scroll_buttons_) {
+    gfx::Size prefsize = prev_button_->GetPreferredSize();
+    prev_button_->SetBounds(0, 0, prefsize.width(), prefsize.height());
+    prefsize = next_button_->GetPreferredSize();
+    if (IsHorizontal()) {
+      next_button_->SetBounds(width() - prefsize.width(), 0, prefsize.width(),
+                              prefsize.height());
+    } else {
+      next_button_->SetBounds(0, height() - prefsize.height(), prefsize.width(),
+                              prefsize.height());
+    }
+  } else {
+    prev_button_->SetBounds(0, 0, 0, 0);
+    next_button_->SetBounds(0, 0, 0, 0);
+  }
+
+  // Size and place the thumb
+  gfx::Size thumb_prefsize = thumb_->GetPreferredSize();
+  gfx::Rect track_bounds = GetTrackBounds();
+
+  // Preserve the height/width of the thumb (depending on orientation) as set
+  // by the last call to |Update|, but coerce the width/height to be the
+  // appropriate value for the bitmaps provided.
+  if (IsHorizontal()) {
+    thumb_->SetBounds(thumb_->x(), thumb_->y(), thumb_->width(),
+                      thumb_prefsize.height());
+  } else {
+    thumb_->SetBounds(thumb_->x(), thumb_->y(), thumb_prefsize.width(),
+                      thumb_->height());
+  }
+
+  // Hide the thumb if the track isn't tall enough to display even a tiny
+  // thumb. The user can only use the mousewheel, scroll buttons or keyboard
+  // in this scenario.
+  if ((IsHorizontal() && (track_bounds.width() < thumb_prefsize.width()) ||
+      (!IsHorizontal() && (track_bounds.height() < thumb_prefsize.height())))) {
+    thumb_->SetVisible(false);
+  } else if (!thumb_->IsVisible()) {
+    thumb_->SetVisible(true);
+  }
+}
+
+bool BitmapScrollBar::OnMousePressed(const MouseEvent& event) {
+  if (event.IsOnlyLeftMouseButton()) {
+    SetThumbTrackState(CustomButton::BS_PUSHED);
+    gfx::Rect thumb_bounds = thumb_->bounds();
+    if (IsHorizontal()) {
+      if (event.x() < thumb_bounds.x()) {
+        last_scroll_amount_ = SCROLL_PREV_PAGE;
+      } else if (event.x() > thumb_bounds.right()) {
+        last_scroll_amount_ = SCROLL_NEXT_PAGE;
+      }
+    } else {
+      if (event.y() < thumb_bounds.y()) {
+        last_scroll_amount_ = SCROLL_PREV_PAGE;
+      } else if (event.y() > thumb_bounds.bottom()) {
+        last_scroll_amount_ = SCROLL_NEXT_PAGE;
+      }
+    }
+    TrackClicked();
+    repeater_.Start();
+  }
+  return true;
+}
+
+void BitmapScrollBar::OnMouseReleased(const MouseEvent& event, bool canceled) {
+  SetThumbTrackState(CustomButton::BS_NORMAL);
+  repeater_.Stop();
+  View::OnMouseReleased(event, canceled);
+}
+
+bool BitmapScrollBar::OnMouseWheel(const MouseWheelEvent& event) {
+  ScrollByContentsOffset(event.GetOffset());
+  return true;
+}
+
+bool BitmapScrollBar::OnKeyPressed(const KeyEvent& event) {
+  ScrollAmount amount = SCROLL_NONE;
+  switch(event.GetCharacter()) {
+    case VK_UP:
+      if (!IsHorizontal())
+        amount = SCROLL_PREV_LINE;
+      break;
+    case VK_DOWN:
+      if (!IsHorizontal())
+        amount = SCROLL_NEXT_LINE;
+      break;
+    case VK_LEFT:
+      if (IsHorizontal())
+        amount = SCROLL_PREV_LINE;
+      break;
+    case VK_RIGHT:
+      if (IsHorizontal())
+        amount = SCROLL_NEXT_LINE;
+      break;
+    case VK_PRIOR:
+      amount = SCROLL_PREV_PAGE;
+      break;
+    case VK_NEXT:
+      amount = SCROLL_NEXT_PAGE;
+      break;
+    case VK_HOME:
+      amount = SCROLL_START;
+      break;
+    case VK_END:
+      amount = SCROLL_END;
+      break;
+  }
+  if (amount != SCROLL_NONE) {
+    ScrollByAmount(amount);
+    return true;
+  }
+  return false;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, ContextMenuController implementation:
+
+enum ScrollBarContextMenuCommands {
+  ScrollBarContextMenuCommand_ScrollHere = 1,
+  ScrollBarContextMenuCommand_ScrollStart,
+  ScrollBarContextMenuCommand_ScrollEnd,
+  ScrollBarContextMenuCommand_ScrollPageUp,
+  ScrollBarContextMenuCommand_ScrollPageDown,
+  ScrollBarContextMenuCommand_ScrollPrev,
+  ScrollBarContextMenuCommand_ScrollNext
+};
+
+void BitmapScrollBar::ShowContextMenu(View* source,
+                                      int x,
+                                      int y,
+                                      bool is_mouse_gesture) {
+  Widget* widget = GetWidget();
+  gfx::Rect widget_bounds;
+  widget->GetBounds(&widget_bounds, true);
+  gfx::Point temp_pt(x - widget_bounds.x(), y - widget_bounds.y());
+  View::ConvertPointFromWidget(this, &temp_pt);
+  context_menu_mouse_position_ = IsHorizontal() ? temp_pt.x() : temp_pt.y();
+
+  Menu menu(this, Menu::TOPLEFT, GetWidget()->GetNativeView());
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollHere);
+  menu.AppendSeparator();
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollStart);
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollEnd);
+  menu.AppendSeparator();
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollPageUp);
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollPageDown);
+  menu.AppendSeparator();
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollPrev);
+  menu.AppendDelegateMenuItem(ScrollBarContextMenuCommand_ScrollNext);
+  menu.RunMenuAt(x, y);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, Menu::Delegate implementation:
+
+std::wstring BitmapScrollBar::GetLabel(int id) const {
+  switch (id) {
+    case ScrollBarContextMenuCommand_ScrollHere:
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLHERE);
+    case ScrollBarContextMenuCommand_ScrollStart:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLLEFTEDGE);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLHOME);
+    case ScrollBarContextMenuCommand_ScrollEnd:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLRIGHTEDGE);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLEND);
+    case ScrollBarContextMenuCommand_ScrollPageUp:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLPAGEUP);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLPAGEUP);
+    case ScrollBarContextMenuCommand_ScrollPageDown:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLPAGEDOWN);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLPAGEDOWN);
+    case ScrollBarContextMenuCommand_ScrollPrev:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLLEFT);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLUP);
+    case ScrollBarContextMenuCommand_ScrollNext:
+      if (IsHorizontal())
+        return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLRIGHT);
+      return l10n_util::GetString(IDS_SCROLLBAR_CXMENU_SCROLLDOWN);
+  }
+  NOTREACHED() << "Invalid BitmapScrollBar Context Menu command!";
+  return L"";
+}
+
+bool BitmapScrollBar::IsCommandEnabled(int id) const {
+  switch (id) {
+    case ScrollBarContextMenuCommand_ScrollPageUp:
+    case ScrollBarContextMenuCommand_ScrollPageDown:
+      return !IsHorizontal();
+  }
+  return true;
+}
+
+void BitmapScrollBar::ExecuteCommand(int id) {
+  switch (id) {
+    case ScrollBarContextMenuCommand_ScrollHere:
+      ScrollToThumbPosition(context_menu_mouse_position_, true);
+      break;
+    case ScrollBarContextMenuCommand_ScrollStart:
+      ScrollByAmount(SCROLL_START);
+      break;
+    case ScrollBarContextMenuCommand_ScrollEnd:
+      ScrollByAmount(SCROLL_END);
+      break;
+    case ScrollBarContextMenuCommand_ScrollPageUp:
+      ScrollByAmount(SCROLL_PREV_PAGE);
+      break;
+    case ScrollBarContextMenuCommand_ScrollPageDown:
+      ScrollByAmount(SCROLL_NEXT_PAGE);
+      break;
+    case ScrollBarContextMenuCommand_ScrollPrev:
+      ScrollByAmount(SCROLL_PREV_LINE);
+      break;
+    case ScrollBarContextMenuCommand_ScrollNext:
+      ScrollByAmount(SCROLL_NEXT_LINE);
+      break;
+  }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, ButtonListener implementation:
+
+void BitmapScrollBar::ButtonPressed(Button* sender) {
+  if (sender == prev_button_) {
+    ScrollByAmount(SCROLL_PREV_LINE);
+  } else if (sender == next_button_) {
+    ScrollByAmount(SCROLL_NEXT_LINE);
+  }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, ScrollBar implementation:
+
+void BitmapScrollBar::Update(int viewport_size, int content_size,
+                             int contents_scroll_offset) {
+  ScrollBar::Update(viewport_size, content_size, contents_scroll_offset);
+
+  // Make sure contents_size is always > 0 to avoid divide by zero errors in
+  // calculations throughout this code.
+  contents_size_ = std::max(1, content_size);
+
+  if (content_size < 0)
+    content_size = 0;
+  if (contents_scroll_offset < 0)
+    contents_scroll_offset = 0;
+  if (contents_scroll_offset > content_size)
+    contents_scroll_offset = content_size;
+
+  // Thumb Height and Thumb Pos.
+  // The height of the thumb is the ratio of the Viewport height to the
+  // content size multiplied by the height of the thumb track.
+  double ratio = static_cast<double>(viewport_size) / contents_size_;
+  int thumb_size = static_cast<int>(ratio * GetTrackSize());
+  thumb_->SetSize(thumb_size);
+
+  int thumb_position = CalculateThumbPosition(contents_scroll_offset);
+  thumb_->SetPosition(thumb_position);
+}
+
+int BitmapScrollBar::GetLayoutSize() const {
+  gfx::Size prefsize = prev_button_->GetPreferredSize();
+  return IsHorizontal() ? prefsize.height() : prefsize.width();
+}
+
+int BitmapScrollBar::GetPosition() const {
+  return thumb_->GetPosition();
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// BitmapScrollBar, private:
+
+void BitmapScrollBar::ScrollContentsToOffset() {
+  GetController()->ScrollToPosition(this, contents_scroll_offset_);
+  thumb_->SetPosition(CalculateThumbPosition(contents_scroll_offset_));
+}
+
+int BitmapScrollBar::GetTrackSize() const {
+  gfx::Rect track_bounds = GetTrackBounds();
+  return IsHorizontal() ? track_bounds.width() : track_bounds.height();
+}
+
+int BitmapScrollBar::CalculateThumbPosition(int contents_scroll_offset) const {
+  return (contents_scroll_offset * GetTrackSize()) / contents_size_;
+}
+
+int BitmapScrollBar::CalculateContentsOffset(int thumb_position,
+                                             bool scroll_to_middle) const {
+  if (scroll_to_middle)
+    thumb_position = thumb_position - (thumb_->GetSize() / 2);
+  return (thumb_position * contents_size_) / GetTrackSize();
+}
+
+void BitmapScrollBar::SetThumbTrackState(CustomButton::ButtonState state) {
+  thumb_track_state_ = state;
+  SchedulePaint();
+}
+
+}  // namespace views