ui/views/controls/tree/tree

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This source file includes following definitions.
text_background_color_id
text_color_id
row_height_
CreateParentIfNecessary
SetModel
SetEditable
StartEditing
CancelEdit
CommitEdit
GetEditingNode
SetSelectedNode
GetSelectedNode
Collapse
Expand
ExpandAll
IsExpanded
SetRootShown
GetNodeForRow
GetRowForNode
Layout
GetPreferredSize
AcceleratorPressed
OnMousePressed
GetTextInputClient
OnGestureEvent
ShowContextMenu
GetAccessibleState
GetClassName
TreeNodesAdded
TreeNodesRemoved
TreeNodeChanged
ContentsChanged
HandleKeyEvent
OnWillChangeFocus
OnDidChangeFocus
GetRowCount
GetSelectedRow
SetSelectedRow
GetTextForRow
GetKeyboardContextMenuLocation
OnKeyPressed
OnPaint
OnFocus
OnBlur
OnClickOrTap
LoadChildren
ConfigureInternalNode
UpdateNodeTextWidth
DrawnNodesChanged
UpdatePreferredSize
LayoutEditor
SchedulePaintForNode
PaintRows
PaintRow
PaintExpandControl
GetInternalNodeForModelNode
GetBoundsForNode
GetBoundsForNodeImpl
GetRowForInternalNode
GetNodeByRow
GetNodeByRowImpl
IncrementSelection
CollapseOrSelectParent
ExpandOrSelectChild
ExpandImpl
text_width_
Reset
NumExpandedNodes
GetMaxWidth
// Copyright (c) 2012 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 "ui/views/controls/tree/tree_view.h"

#include <algorithm>

#include "base/i18n/rtl.h"
#include "base/message_loop/message_loop.h"
#include "grit/ui_resources.h"
#include "ui/accessibility/ax_view_state.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/events/event.h"
#include "ui/events/keycodes/keyboard_codes.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/image/image.h"
#include "ui/gfx/rect_conversions.h"
#include "ui/gfx/skia_util.h"
#include "ui/native_theme/native_theme.h"
#include "ui/views/controls/prefix_selector.h"
#include "ui/views/controls/scroll_view.h"
#include "ui/views/controls/textfield/textfield.h"
#include "ui/views/controls/tree/tree_view_controller.h"
#include "ui/views/ime/input_method.h"

using ui::TreeModel;
using ui::TreeModelNode;

namespace views {

// Insets around the view.
static const int kHorizontalInset = 2;
static const int kVerticalInset = 2;
// Padding before/after the image.
static const int kImagePadding = 4;
// Size of the arrow region.
static const int kArrowRegionSize = 12;
// Padding around the text (on each side).
static const int kTextVerticalPadding = 3;
static const int kTextHorizontalPadding = 2;
// How much children are indented from their parent.
static const int kIndent = 20;

// static
const char TreeView::kViewClassName[] = "TreeView";

namespace {

// Returns the color id for the background of selected text. |has_focus|
// indicates if the tree has focus.
ui::NativeTheme::ColorId text_background_color_id(bool has_focus) {
  return has_focus ?
      ui::NativeTheme::kColorId_TreeSelectionBackgroundFocused :
      ui::NativeTheme::kColorId_TreeSelectionBackgroundUnfocused;
}

// Returns the color id for text. |has_focus| indicates if the tree has focus
// and |is_selected| is true if the item is selected.
ui::NativeTheme::ColorId text_color_id(bool has_focus, bool is_selected) {
  if (is_selected) {
    if (has_focus)
      return ui::NativeTheme::kColorId_TreeSelectedText;
    return ui::NativeTheme::kColorId_TreeSelectedTextUnfocused;
  }
  return ui::NativeTheme::kColorId_TreeText;
}

}  // namespace

TreeView::TreeView()
    : model_(NULL),
      selected_node_(NULL),
      editing_(false),
      editor_(NULL),
      focus_manager_(NULL),
      auto_expand_children_(false),
      editable_(true),
      controller_(NULL),
      root_shown_(true),
      has_custom_icons_(false),
      row_height_(font_list_.GetHeight() + kTextVerticalPadding * 2) {
  SetFocusable(true);
  closed_icon_ = *ui::ResourceBundle::GetSharedInstance().GetImageNamed(
      (base::i18n::IsRTL() ? IDR_FOLDER_CLOSED_RTL
                           : IDR_FOLDER_CLOSED)).ToImageSkia();
  open_icon_ = *ui::ResourceBundle::GetSharedInstance().GetImageNamed(
      (base::i18n::IsRTL() ? IDR_FOLDER_OPEN_RTL
                           : IDR_FOLDER_OPEN)).ToImageSkia();
  text_offset_ = closed_icon_.width() + kImagePadding + kImagePadding +
      kArrowRegionSize;
}

TreeView::~TreeView() {
  if (model_)
    model_->RemoveObserver(this);
  if (focus_manager_) {
    focus_manager_->RemoveFocusChangeListener(this);
    focus_manager_ = NULL;
  }
}

View* TreeView::CreateParentIfNecessary() {
  ScrollView* scroll_view = ScrollView::CreateScrollViewWithBorder();
  scroll_view->SetContents(this);
  return scroll_view;
}

void TreeView::SetModel(TreeModel* model) {
  if (model == model_)
    return;
  if (model_)
    model_->RemoveObserver(this);

  CancelEdit();

  model_ = model;
  selected_node_ = NULL;
  icons_.clear();
  if (model_) {
    model_->AddObserver(this);
    model_->GetIcons(&icons_);

    root_.RemoveAll();
    ConfigureInternalNode(model_->GetRoot(), &root_);
    LoadChildren(&root_);
    root_.set_is_expanded(true);
    if (root_shown_)
      selected_node_ = &root_;
    else if (root_.child_count())
      selected_node_ = root_.GetChild(0);
  }
  DrawnNodesChanged();
}

void TreeView::SetEditable(bool editable) {
  if (editable == editable_)
    return;
  editable_ = editable;
  CancelEdit();
}

void TreeView::StartEditing(TreeModelNode* node) {
  DCHECK(node);
  // Cancel the current edit.
  CancelEdit();
  // Make sure all ancestors are expanded.
  if (model_->GetParent(node))
    Expand(model_->GetParent(node));
  // Select the node, else if the user commits the edit the selection reverts.
  SetSelectedNode(node);
  if (GetSelectedNode() != node)
    return;  // Selection failed for some reason, don't start editing.
  DCHECK(!editing_);
  editing_ = true;
  if (!editor_) {
    editor_ = new Textfield;
    // Add the editor immediately as GetPreferredSize returns the wrong thing if
    // not parented.
    AddChildView(editor_);
    editor_->SetFontList(font_list_);
    empty_editor_size_ = editor_->GetPreferredSize();
    editor_->set_controller(this);
  }
  editor_->SetText(selected_node_->model_node()->GetTitle());
  LayoutEditor();
  editor_->SetVisible(true);
  SchedulePaintForNode(selected_node_);
  editor_->RequestFocus();
  editor_->SelectAll(false);

  // Listen for focus changes so that we can cancel editing.
  focus_manager_ = GetFocusManager();
  if (focus_manager_)
    focus_manager_->AddFocusChangeListener(this);

  // Accelerators to commit/cancel edit.
  AddAccelerator(ui::Accelerator(ui::VKEY_RETURN, ui::EF_NONE));
  AddAccelerator(ui::Accelerator(ui::VKEY_ESCAPE, ui::EF_NONE));
}

void TreeView::CancelEdit() {
  if (!editing_)
    return;

  // WARNING: don't touch |selected_node_|, it may be bogus.

  editing_ = false;
  if (focus_manager_) {
    focus_manager_->RemoveFocusChangeListener(this);
    focus_manager_ = NULL;
  }
  editor_->SetVisible(false);
  SchedulePaint();

  RemoveAccelerator(ui::Accelerator(ui::VKEY_RETURN, ui::EF_NONE));
  RemoveAccelerator(ui::Accelerator(ui::VKEY_ESCAPE, ui::EF_NONE));
}

void TreeView::CommitEdit() {
  if (!editing_)
    return;

  DCHECK(selected_node_);
  const bool editor_has_focus = editor_->HasFocus();
  model_->SetTitle(GetSelectedNode(), editor_->text());
  CancelEdit();
  if (editor_has_focus)
    RequestFocus();
}

TreeModelNode* TreeView::GetEditingNode() {
  return editing_ ? selected_node_->model_node() : NULL;
}

void TreeView::SetSelectedNode(TreeModelNode* model_node) {
  if (editing_ || model_node != selected_node_)
    CancelEdit();
  if (model_node && model_->GetParent(model_node))
    Expand(model_->GetParent(model_node));
  if (model_node && model_node == root_.model_node() && !root_shown_)
    return;  // Ignore requests to select the root when not shown.
  InternalNode* node = model_node ? GetInternalNodeForModelNode(
      model_node, CREATE_IF_NOT_LOADED) : NULL;
  bool was_empty_selection = (selected_node_ == NULL);
  bool changed = (selected_node_ != node);
  if (changed) {
    SchedulePaintForNode(selected_node_);
    selected_node_ = node;
    if (selected_node_ == &root_ && !root_shown_)
      selected_node_ = NULL;
    if (selected_node_ && selected_node_ != &root_)
      Expand(model_->GetParent(selected_node_->model_node()));
    SchedulePaintForNode(selected_node_);
  }

  if (selected_node_)
    ScrollRectToVisible(GetBoundsForNode(selected_node_));

  // Notify controller if the old selection was empty to handle the case of
  // remove explicitly resetting selected_node_ before invoking this.
  if (controller_ && (changed || was_empty_selection))
    controller_->OnTreeViewSelectionChanged(this);

  if (changed) {
    // TODO(dmazzoni): Decide if EVENT_SELECTION_CHANGED is a better choice for
    // sub-item selection event.
    NotifyAccessibilityEvent(ui::AX_EVENT_FOCUS, true);
  }
}

TreeModelNode* TreeView::GetSelectedNode() {
  return selected_node_ ? selected_node_->model_node() : NULL;
}

void TreeView::Collapse(ui::TreeModelNode* model_node) {
  // Don't collapse the root if the root isn't shown, otherwise nothing is
  // displayed.
  if (model_node == root_.model_node() && !root_shown_)
    return;
  InternalNode* node =
      GetInternalNodeForModelNode(model_node, DONT_CREATE_IF_NOT_LOADED);
  if (!node)
    return;
  bool was_expanded = IsExpanded(model_node);
  if (node->is_expanded()) {
    if (selected_node_ && selected_node_->HasAncestor(node))
      SetSelectedNode(model_node);
    node->set_is_expanded(false);
  }
  if (was_expanded)
    DrawnNodesChanged();
}

void TreeView::Expand(TreeModelNode* node) {
  if (ExpandImpl(node))
    DrawnNodesChanged();
  // TODO: need to support auto_expand_children_.
}

void TreeView::ExpandAll(TreeModelNode* node) {
  DCHECK(node);
  // Expand the node.
  bool expanded_at_least_one = ExpandImpl(node);
  // And recursively expand all the children.
  for (int i = model_->GetChildCount(node) - 1; i >= 0; --i) {
    TreeModelNode* child = model_->GetChild(node, i);
    if (ExpandImpl(child))
      expanded_at_least_one = true;
  }
  if (expanded_at_least_one)
    DrawnNodesChanged();
}

bool TreeView::IsExpanded(TreeModelNode* model_node) {
  if (!model_node) {
    // NULL check primarily for convenience for uses in this class so don't have
    // to add NULL checks every where we look up the parent.
    return true;
  }
  InternalNode* node = GetInternalNodeForModelNode(
      model_node, DONT_CREATE_IF_NOT_LOADED);
  if (!node)
    return false;

  while (node) {
    if (!node->is_expanded())
      return false;
    node = node->parent();
  }
  return true;
}

void TreeView::SetRootShown(bool root_shown) {
  if (root_shown_ == root_shown)
    return;
  root_shown_ = root_shown;
  if (!root_shown_ && selected_node_ == &root_) {
    if (model_->GetChildCount(root_.model_node()))
      SetSelectedNode(model_->GetChild(root_.model_node(), 0));
    else
      SetSelectedNode(NULL);
  }
  DrawnNodesChanged();
}

ui::TreeModelNode* TreeView::GetNodeForRow(int row) {
  int depth = 0;
  InternalNode* node = GetNodeByRow(row, &depth);
  return node ? node->model_node() : NULL;
}

int TreeView::GetRowForNode(ui::TreeModelNode* node) {
  InternalNode* internal_node =
      GetInternalNodeForModelNode(node, DONT_CREATE_IF_NOT_LOADED);
  if (!internal_node)
    return -1;
  int depth = 0;
  return GetRowForInternalNode(internal_node, &depth);
}

void TreeView::Layout() {
  int width = preferred_size_.width();
  int height = preferred_size_.height();
  if (parent()) {
    width = std::max(parent()->width(), width);
    height = std::max(parent()->height(), height);
  }
  SetBounds(x(), y(), width, height);
  LayoutEditor();
}

gfx::Size TreeView::GetPreferredSize() {
  return preferred_size_;
}

bool TreeView::AcceleratorPressed(const ui::Accelerator& accelerator) {
  if (accelerator.key_code() == ui::VKEY_RETURN) {
    CommitEdit();
  } else {
    DCHECK_EQ(ui::VKEY_ESCAPE, accelerator.key_code());
    CancelEdit();
    RequestFocus();
  }
  return true;
}

bool TreeView::OnMousePressed(const ui::MouseEvent& event) {
  return OnClickOrTap(event);
}

ui::TextInputClient* TreeView::GetTextInputClient() {
  if (!selector_)
    selector_.reset(new PrefixSelector(this));
  return selector_.get();
}

void TreeView::OnGestureEvent(ui::GestureEvent* event) {
  if (event->type() == ui::ET_GESTURE_TAP) {
    if (OnClickOrTap(*event))
      event->SetHandled();
  }
}

void TreeView::ShowContextMenu(const gfx::Point& p,
                               ui::MenuSourceType source_type) {
  if (!model_)
    return;
  if (source_type == ui::MENU_SOURCE_MOUSE) {
    // Only invoke View's implementation (which notifies the
    // ContextMenuController) if over a node.
    gfx::Point local_point(p);
    ConvertPointFromScreen(this, &local_point);
    int row = (local_point.y() - kVerticalInset) / row_height_;
    int depth = 0;
    InternalNode* node = GetNodeByRow(row, &depth);
    if (!node)
      return;
    gfx::Rect bounds(GetBoundsForNodeImpl(node, row, depth));
    if (!bounds.Contains(local_point))
      return;
  }
  View::ShowContextMenu(p, source_type);
}

void TreeView::GetAccessibleState(ui::AXViewState* state) {
  state->role = ui::AX_ROLE_TREE;
  state->AddStateFlag(ui::AX_STATE_READ_ONLY);
  if (!selected_node_)
    return;

  // Get selected item info.
  state->role = ui::AX_ROLE_TREE_ITEM;
  state->name = selected_node_->model_node()->GetTitle();
}

const char* TreeView::GetClassName() const {
  return kViewClassName;
}

void TreeView::TreeNodesAdded(TreeModel* model,
                              TreeModelNode* parent,
                              int start,
                              int count) {
  InternalNode* parent_node =
      GetInternalNodeForModelNode(parent, DONT_CREATE_IF_NOT_LOADED);
  if (!parent_node || !parent_node->loaded_children())
    return;
  for (int i = 0; i < count; ++i) {
    InternalNode* child = new InternalNode;
    ConfigureInternalNode(model_->GetChild(parent, start + i), child);
    parent_node->Add(child, start + i);
  }
  if (IsExpanded(parent))
    DrawnNodesChanged();
}

void TreeView::TreeNodesRemoved(TreeModel* model,
                                TreeModelNode* parent,
                                int start,
                                int count) {
  InternalNode* parent_node =
      GetInternalNodeForModelNode(parent, DONT_CREATE_IF_NOT_LOADED);
  if (!parent_node || !parent_node->loaded_children())
    return;
  bool reset_selection = false;
  for (int i = 0; i < count; ++i) {
    InternalNode* child_removing = parent_node->GetChild(start);
    if (selected_node_ && selected_node_->HasAncestor(child_removing))
      reset_selection = true;
    delete parent_node->Remove(child_removing);
  }
  if (reset_selection) {
    // selected_node_ is no longer valid (at the time we enter this function
    // its model_node() is likely deleted). Explicitly NULL out the field
    // rather than invoking SetSelectedNode() otherwise, we'll try and use a
    // deleted value.
    selected_node_ = NULL;
    TreeModelNode* to_select = parent;
    if (parent == root_.model_node() && !root_shown_) {
      to_select = model_->GetChildCount(parent) > 0 ?
          model_->GetChild(parent, 0) : NULL;
    }
    SetSelectedNode(to_select);
  }
  if (IsExpanded(parent))
    DrawnNodesChanged();
}

void TreeView::TreeNodeChanged(TreeModel* model, TreeModelNode* model_node) {
  InternalNode* node =
      GetInternalNodeForModelNode(model_node, DONT_CREATE_IF_NOT_LOADED);
  if (!node)
    return;
  int old_width = node->text_width();
  UpdateNodeTextWidth(node);
  if (old_width != node->text_width() &&
      ((node == &root_ && root_shown_) ||
       (node != &root_ && IsExpanded(node->parent()->model_node())))) {
    DrawnNodesChanged();
  }
}

void TreeView::ContentsChanged(Textfield* sender,
                               const base::string16& new_contents) {
}

bool TreeView::HandleKeyEvent(Textfield* sender,
                              const ui::KeyEvent& key_event) {
  switch (key_event.key_code()) {
    case ui::VKEY_RETURN:
      CommitEdit();
      return true;

    case ui::VKEY_ESCAPE:
      CancelEdit();
      RequestFocus();
      return true;

    default:
      return false;
  }
}

void TreeView::OnWillChangeFocus(View* focused_before, View* focused_now) {
}

void TreeView::OnDidChangeFocus(View* focused_before, View* focused_now) {
  CommitEdit();
}

int TreeView::GetRowCount() {
  int row_count = root_.NumExpandedNodes();
  if (!root_shown_)
    row_count--;
  return row_count;
}

int TreeView::GetSelectedRow() {
  ui::TreeModelNode* model_node = GetSelectedNode();
  return model_node ? GetRowForNode(model_node) : -1;
}

void TreeView::SetSelectedRow(int row) {
  SetSelectedNode(GetNodeForRow(row));
}

base::string16 TreeView::GetTextForRow(int row) {
  return GetNodeForRow(row)->GetTitle();
}

gfx::Point TreeView::GetKeyboardContextMenuLocation() {
  int y = height() / 2;
  if (selected_node_) {
    gfx::Rect node_bounds(GetBoundsForNode(selected_node_));
    gfx::Rect vis_bounds(GetVisibleBounds());
    if (node_bounds.y() >= vis_bounds.y() &&
        node_bounds.y() < vis_bounds.bottom()) {
      y = node_bounds.y();
    }
  }
  gfx::Point screen_loc(0, y);
  if (base::i18n::IsRTL())
    screen_loc.set_x(width());
  ConvertPointToScreen(this, &screen_loc);
  return screen_loc;
}

bool TreeView::OnKeyPressed(const ui::KeyEvent& event) {
  if (!HasFocus())
    return false;

  switch (event.key_code()) {
    case ui::VKEY_F2:
      if (!editing_) {
        TreeModelNode* selected_node = GetSelectedNode();
        if (selected_node && (!controller_ ||
                              controller_->CanEdit(this, selected_node))) {
          StartEditing(selected_node);
        }
      }
      return true;

    case ui::VKEY_UP:
    case ui::VKEY_DOWN:
      IncrementSelection(event.key_code() == ui::VKEY_UP ?
                         INCREMENT_PREVIOUS : INCREMENT_NEXT);
      return true;

    case ui::VKEY_LEFT:
      if (base::i18n::IsRTL())
        ExpandOrSelectChild();
      else
        CollapseOrSelectParent();
      return true;

    case ui::VKEY_RIGHT:
      if (base::i18n::IsRTL())
        CollapseOrSelectParent();
      else
        ExpandOrSelectChild();
      return true;

    default:
      break;
  }
  return false;
}

void TreeView::OnPaint(gfx::Canvas* canvas) {
  // Don't invoke View::OnPaint so that we can render our own focus border.
  canvas->DrawColor(GetNativeTheme()->GetSystemColor(
                        ui::NativeTheme::kColorId_TreeBackground));

  int min_y, max_y;
  {
    SkRect sk_clip_rect;
    if (canvas->sk_canvas()->getClipBounds(&sk_clip_rect)) {
      // Pixels partially inside the clip rect should be included.
      gfx::Rect clip_rect = gfx::ToEnclosingRect(
          gfx::SkRectToRectF(sk_clip_rect));
      min_y = clip_rect.y();
      max_y = clip_rect.bottom();
    } else {
      gfx::Rect vis_bounds = GetVisibleBounds();
      min_y = vis_bounds.y();
      max_y = vis_bounds.bottom();
    }
  }

  int min_row = std::max(0, (min_y - kVerticalInset) / row_height_);
  int max_row = (max_y - kVerticalInset) / row_height_;
  if ((max_y - kVerticalInset) % row_height_ != 0)
    max_row++;
  int current_row = root_row();
  PaintRows(canvas, min_row, max_row, &root_, root_depth(), &current_row);
}

void TreeView::OnFocus() {
  GetInputMethod()->OnFocus();
  View::OnFocus();
  SchedulePaintForNode(selected_node_);

  // Notify the InputMethod so that it knows to query the TextInputClient.
  if (GetInputMethod())
    GetInputMethod()->OnCaretBoundsChanged(this);
}

void TreeView::OnBlur() {
  GetInputMethod()->OnBlur();
  SchedulePaintForNode(selected_node_);
  if (selector_)
    selector_->OnViewBlur();
}

bool TreeView::OnClickOrTap(const ui::LocatedEvent& event) {
  CommitEdit();
  RequestFocus();

  int row = (event.y() - kVerticalInset) / row_height_;
  int depth = 0;
  InternalNode* node = GetNodeByRow(row, &depth);
  if (node) {
    gfx::Rect bounds(GetBoundsForNodeImpl(node, row, depth));
    if (bounds.Contains(event.location())) {
      int relative_x = event.x() - bounds.x();
      if (base::i18n::IsRTL())
        relative_x = bounds.width() - relative_x;
      if (relative_x < kArrowRegionSize &&
          model_->GetChildCount(node->model_node())) {
        if (node->is_expanded())
          Collapse(node->model_node());
        else
          Expand(node->model_node());
      } else if (relative_x > kArrowRegionSize) {
        SetSelectedNode(node->model_node());
        bool should_toggle = false;
        if (event.type() == ui::ET_GESTURE_TAP) {
          const ui::GestureEvent& gesture =
              static_cast<const ui::GestureEvent&>(event);
          should_toggle = gesture.details().tap_count() == 2;
        } else {
          should_toggle = (event.flags() & ui::EF_IS_DOUBLE_CLICK) != 0;
        }
        if (should_toggle) {
          if (node->is_expanded())
            Collapse(node->model_node());
          else
            Expand(node->model_node());
        }
      }
    }
  }
  return true;
}

void TreeView::LoadChildren(InternalNode* node) {
  DCHECK_EQ(0, node->child_count());
  DCHECK(!node->loaded_children());
  node->set_loaded_children(true);
  for (int i = 0, child_count = model_->GetChildCount(node->model_node());
       i < child_count; ++i) {
    InternalNode* child = new InternalNode;
    ConfigureInternalNode(model_->GetChild(node->model_node(), i), child);
    node->Add(child, node->child_count());
  }
}

void TreeView::ConfigureInternalNode(TreeModelNode* model_node,
                                     InternalNode* node) {
  node->Reset(model_node);
  UpdateNodeTextWidth(node);
}

void TreeView::UpdateNodeTextWidth(InternalNode* node) {
  int width = 0, height = 0;
  gfx::Canvas::SizeStringInt(node->model_node()->GetTitle(), font_list_,
                             &width, &height, 0, gfx::Canvas::NO_ELLIPSIS);
  node->set_text_width(width);
}

void TreeView::DrawnNodesChanged() {
  UpdatePreferredSize();
  PreferredSizeChanged();
  SchedulePaint();
}

void TreeView::UpdatePreferredSize() {
  preferred_size_ = gfx::Size();
  if (!model_)
    return;

  preferred_size_.SetSize(
      root_.GetMaxWidth(text_offset_, root_shown_ ? 1 : 0) +
      kTextHorizontalPadding * 2,
      row_height_ * GetRowCount() + kVerticalInset * 2);
}

void TreeView::LayoutEditor() {
  if (!editing_)
    return;

  DCHECK(selected_node_);
  // Position the editor so that its text aligns with the text we drew.
  gfx::Rect row_bounds = GetBoundsForNode(selected_node_);
  row_bounds.set_x(
      GetMirroredXWithWidthInView(row_bounds.x(), row_bounds.width()));
  row_bounds.set_x(row_bounds.x() + text_offset_);
  row_bounds.set_width(row_bounds.width() - text_offset_);
  row_bounds.Inset(kTextHorizontalPadding, kTextVerticalPadding);
  row_bounds.Inset(-empty_editor_size_.width() / 2,
                   -(empty_editor_size_.height() - font_list_.GetHeight()) / 2);
  // Give a little extra space for editing.
  row_bounds.set_width(row_bounds.width() + 50);
  editor_->SetBoundsRect(row_bounds);
  editor_->Layout();
}

void TreeView::SchedulePaintForNode(InternalNode* node) {
  if (!node)
    return;  // Explicitly allow NULL to be passed in.
  SchedulePaintInRect(GetBoundsForNode(node));
}

void TreeView::PaintRows(gfx::Canvas* canvas,
                         int min_row,
                         int max_row,
                         InternalNode* node,
                         int depth,
                         int* row) {
  if (*row >= max_row)
    return;

  if (*row >= min_row && *row < max_row)
    PaintRow(canvas, node, *row, depth);
  (*row)++;
  if (!node->is_expanded())
    return;
  depth++;
  for (int i = 0; i < node->child_count() && *row < max_row; ++i)
    PaintRows(canvas, min_row, max_row, node->GetChild(i), depth, row);
}

void TreeView::PaintRow(gfx::Canvas* canvas,
                        InternalNode* node,
                        int row,
                        int depth) {
  gfx::Rect bounds(GetBoundsForNodeImpl(node, row, depth));

  if (model_->GetChildCount(node->model_node()))
    PaintExpandControl(canvas, bounds, node->is_expanded());

  // Paint the icon.
  gfx::ImageSkia icon;
  int icon_index = model_->GetIconIndex(node->model_node());
  if (icon_index != -1)
    icon = icons_[icon_index];
  else if (node == selected_node_)
    icon = open_icon_;
  else
    icon = closed_icon_;
  int icon_x = kArrowRegionSize + kImagePadding +
               (open_icon_.width() - icon.width()) / 2;
  if (base::i18n::IsRTL())
    icon_x = bounds.right() - icon_x - open_icon_.width();
  else
    icon_x += bounds.x();
  canvas->DrawImageInt(
      icon, icon_x,
      bounds.y() + (bounds.height() - icon.height()) / 2);

  if (!editing_ || node != selected_node_) {
    gfx::Rect text_bounds(bounds.x() + text_offset_, bounds.y(),
                          bounds.width() - text_offset_, bounds.height());
    if (base::i18n::IsRTL())
      text_bounds.set_x(bounds.x());
    if (node == selected_node_) {
      const SkColor bg_color = GetNativeTheme()->GetSystemColor(
          text_background_color_id(HasFocus()));
      canvas->FillRect(text_bounds, bg_color);
      if (HasFocus())
        canvas->DrawFocusRect(text_bounds);
    }
    const ui::NativeTheme::ColorId color_id =
        text_color_id(HasFocus(), node == selected_node_);
    const gfx::Rect internal_bounds(
        text_bounds.x() + kTextHorizontalPadding,
        text_bounds.y() + kTextVerticalPadding,
        text_bounds.width() - kTextHorizontalPadding * 2,
        text_bounds.height() - kTextVerticalPadding * 2);
    canvas->DrawStringRect(node->model_node()->GetTitle(), font_list_,
                           GetNativeTheme()->GetSystemColor(color_id),
                           internal_bounds);
  }
}

void TreeView::PaintExpandControl(gfx::Canvas* canvas,
                                  const gfx::Rect& node_bounds,
                                  bool expanded) {
  int center_x;
  if (base::i18n::IsRTL()) {
    center_x = node_bounds.right() - kArrowRegionSize +
               (kArrowRegionSize - 4) / 2;
  } else {
    center_x = node_bounds.x() + (kArrowRegionSize - 4) / 2;
  }
  int center_y = node_bounds.y() + node_bounds.height() / 2;
  const SkColor arrow_color = GetNativeTheme()->GetSystemColor(
      ui::NativeTheme::kColorId_TreeArrow);
  // TODO: this should come from an image.
  if (!expanded) {
    int delta = base::i18n::IsRTL() ? 1 : -1;
    for (int i = 0; i < 4; ++i) {
      canvas->FillRect(gfx::Rect(center_x + delta * (2 - i),
                                 center_y - (3 - i), 1, (3 - i) * 2 + 1),
                       arrow_color);
    }
  } else {
    center_y -= 2;
    for (int i = 0; i < 4; ++i) {
      canvas->FillRect(gfx::Rect(center_x - (3 - i), center_y + i,
                                 (3 - i) * 2 + 1, 1), arrow_color);
    }
  }
}

TreeView::InternalNode* TreeView::GetInternalNodeForModelNode(
    ui::TreeModelNode* model_node,
    GetInternalNodeCreateType create_type) {
  if (model_node == root_.model_node())
    return &root_;
  InternalNode* parent_internal_node =
      GetInternalNodeForModelNode(model_->GetParent(model_node), create_type);
  if (!parent_internal_node)
    return NULL;
  if (!parent_internal_node->loaded_children()) {
    if (create_type == DONT_CREATE_IF_NOT_LOADED)
      return NULL;
    LoadChildren(parent_internal_node);
  }
  return parent_internal_node->GetChild(
      model_->GetIndexOf(parent_internal_node->model_node(), model_node));
}

gfx::Rect TreeView::GetBoundsForNode(InternalNode* node) {
  int row, depth;
  row = GetRowForInternalNode(node, &depth);
  return GetBoundsForNodeImpl(node, row, depth);
}

gfx::Rect TreeView::GetBoundsForNodeImpl(InternalNode* node,
                                         int row,
                                         int depth) {
  gfx::Rect rect(depth * kIndent + kHorizontalInset,
                 row * row_height_ + kVerticalInset,
                 text_offset_ + node->text_width() +
                 kTextHorizontalPadding * 2,
                 row_height_);
  rect.set_x(GetMirroredXWithWidthInView(rect.x(), rect.width()));
  return rect;
}

int TreeView::GetRowForInternalNode(InternalNode* node, int* depth) {
  DCHECK(!node->parent() || IsExpanded(node->parent()->model_node()));
  *depth = -1;
  int row = -1;
  InternalNode* tmp_node = node;
  while (tmp_node->parent()) {
    int index_in_parent = tmp_node->parent()->GetIndexOf(tmp_node);
    (*depth)++;
    row++;  // For node.
    for (int i = 0; i < index_in_parent; ++i)
      row += tmp_node->parent()->GetChild(i)->NumExpandedNodes();
    tmp_node = tmp_node->parent();
  }
  if (root_shown_) {
    (*depth)++;
    row++;
  }
  return row;
}

TreeView::InternalNode* TreeView::GetNodeByRow(int row, int* depth) {
  int current_row = root_row();
  *depth = 0;
  return GetNodeByRowImpl(&root_, row, root_depth(), &current_row, depth);
}

TreeView::InternalNode* TreeView::GetNodeByRowImpl(InternalNode* node,
                                                   int target_row,
                                                   int current_depth,
                                                   int* current_row,
                                                   int* node_depth) {
  if (*current_row == target_row) {
    *node_depth = current_depth;
    return node;
  }
  (*current_row)++;
  if (node->is_expanded()) {
    current_depth++;
    for (int i = 0; i < node->child_count(); ++i) {
      InternalNode* result = GetNodeByRowImpl(
          node->GetChild(i), target_row, current_depth, current_row,
          node_depth);
      if (result)
        return result;
    }
  }
  return NULL;
}

void TreeView::IncrementSelection(IncrementType type) {
  if (!model_)
    return;

  if (!GetSelectedNode()) {
    // If nothing is selected select the first or last node.
    if (!root_.child_count())
      return;
    if (type == INCREMENT_PREVIOUS) {
      int row_count = GetRowCount();
      int depth = 0;
      DCHECK(row_count);
      InternalNode* node = GetNodeByRow(row_count - 1, &depth);
      SetSelectedNode(node->model_node());
    } else if (root_shown_) {
      SetSelectedNode(root_.model_node());
    } else {
      SetSelectedNode(root_.GetChild(0)->model_node());
    }
    return;
  }

  int depth = 0;
  int delta = type == INCREMENT_PREVIOUS ? -1 : 1;
  int row = GetRowForInternalNode(selected_node_, &depth);
  int new_row = std::min(GetRowCount() - 1, std::max(0, row + delta));
  if (new_row == row)
    return;  // At the end/beginning.
  SetSelectedNode(GetNodeByRow(new_row, &depth)->model_node());
}

void TreeView::CollapseOrSelectParent() {
  if (selected_node_) {
    if (selected_node_->is_expanded())
      Collapse(selected_node_->model_node());
    else if (selected_node_->parent())
      SetSelectedNode(selected_node_->parent()->model_node());
  }
}

void TreeView::ExpandOrSelectChild() {
  if (selected_node_) {
    if (!selected_node_->is_expanded())
      Expand(selected_node_->model_node());
    else if (selected_node_->child_count())
      SetSelectedNode(selected_node_->GetChild(0)->model_node());
  }
}

bool TreeView::ExpandImpl(TreeModelNode* model_node) {
  TreeModelNode* parent = model_->GetParent(model_node);
  if (!parent) {
    // Node should be the root.
    DCHECK_EQ(root_.model_node(), model_node);
    bool was_expanded = root_.is_expanded();
    root_.set_is_expanded(true);
    return !was_expanded;
  }

  // Expand all the parents.
  bool return_value = ExpandImpl(parent);
  InternalNode* internal_node =
      GetInternalNodeForModelNode(model_node, CREATE_IF_NOT_LOADED);
  DCHECK(internal_node);
  if (!internal_node->is_expanded()) {
    if (!internal_node->loaded_children())
      LoadChildren(internal_node);
    internal_node->set_is_expanded(true);
    return_value = true;
  }
  return return_value;
}

// InternalNode ----------------------------------------------------------------

TreeView::InternalNode::InternalNode()
    : model_node_(NULL),
      loaded_children_(false),
      is_expanded_(false),
      text_width_(0) {
}

TreeView::InternalNode::~InternalNode() {
}

void TreeView::InternalNode::Reset(ui::TreeModelNode* node) {
  model_node_ = node;
  loaded_children_ = false;
  is_expanded_ = false;
  text_width_ = 0;
}

int TreeView::InternalNode::NumExpandedNodes() const {
  int result = 1;  // For this.
  if (!is_expanded_)
    return result;
  for (int i = 0; i < child_count(); ++i)
    result += GetChild(i)->NumExpandedNodes();
  return result;
}

int TreeView::InternalNode::GetMaxWidth(int indent, int depth) {
  int max_width = text_width_ + indent * depth;
  if (!is_expanded_)
    return max_width;
  for (int i = 0; i < child_count(); ++i) {
    max_width = std::max(max_width,
                         GetChild(i)->GetMaxWidth(indent, depth + 1));
  }
  return max_width;
}

}  // namespace views
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root/ui/views/controls/tree/tree_view.cc

DEFINITIONS
