Added basic accessibility to TreeView.

ui/views/controls/tree/tree_view.cc

 // 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"
@@ skipping 24 matching lines @@
 // 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;
 }
 
@@ skipping 167 matching lines @@
   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_);
+
+    NotifyAccessibilityEvent(ui::AccessibilityTypes::EVENT_FOCUS, true);

[dmazzoni, 2013/11/22 23:45:30]

I'm tempted to use EVENT_SELECTION_CHANGED here (seems more accurate) but go
ahead and plumb it through to a focus event inside the event router. OK to leave
alone if that doesn't work or complicates things a lot for some reason.

[zel, 2013/11/23 00:17:16]

I will add TODO here to address this later.

I picked EVENT_FOCUS since that how it seemed other controls, like menu, were
handling item selection.

   }
 
   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);
 }
@@ skipping 148 matching lines @@
     gfx::Rect bounds(GetBoundsForNodeImpl(node, row, depth));
     if (!bounds.Contains(local_point))
       return;
   }
   View::ShowContextMenu(p, source_type);
 }
 
 void TreeView::GetAccessibleState(ui::AccessibleViewState* state) {
   state->role = ui::AccessibilityTypes::ROLE_OUTLINE;
   state->state = ui::AccessibilityTypes::STATE_READONLY;
+  if (!selected_node_ || !selected_node_->model_node())
+    return;
+
+  // Get selected item info.
+  state->role = ui::AccessibilityTypes::ROLE_OUTLINEITEM;
+  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;
@@ skipping 604 matching lines @@
   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