ui/accessibility/ax_node.h

   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 #ifndef UI_ACCESSIBILITY_AX_NODE_H_
   6 #define UI_ACCESSIBILITY_AX_NODE_H_
   7
   8 #include "ui/accessibility/ax_node_data.h"
   9
  10 namespace ui {
  11
  12 // One node in an AXTree.
  13 class AX_EXPORT AXNode {
  14  public:
  15   // The constructor requires a parent, id, and index in parent, but
  16   // the data is not required. After initialization, only index_in_parent
  17   // is allowed to change, the others are guaranteed to never change.
  18   AXNode(AXNode* parent, int32 id, int32 index_in_parent);
  19   virtual ~AXNode();
  20
  21   // Accessors.
  22   int32 id() const { return data_.id; }
  23   AXNode* parent() const { return parent_; }
  24   int child_count() const { return static_cast<int>(children_.size()); }
  25   const AXNodeData& data() const { return data_; }
  26   const std::vector<AXNode*>& children() const { return children_; }
  27   int index_in_parent() const { return index_in_parent_; }
  28
  29   // Get the child at the given index.
  30   AXNode* ChildAtIndex(int index) const { return children_[index]; }
  31
  32   // Set the node's accessibility data. This may be done during initial
  33   // initialization or later when the node data changes.
  34   void SetData(const AXNodeData& src);
  35
  36   // Update this node's location. This is separate from SetData just because
  37   // changing only the location is common and should be more efficient than
  38   // re-copying all of the data.
  39   void SetLocation(const gfx::Rect& new_location);
  40
  41   // Set the index in parent, for example if siblings were inserted or deleted.
  42   void SetIndexInParent(int index_in_parent);
  43
  44   // Swap the internal children vector with |children|. This instance
  45   // now owns all of the passed children.
  46   void SwapChildren(std::vector<AXNode*>& children);
  47
  48   // This is called when the AXTree no longer includes this node in the
  49   // tree. Reference counting is used on some platforms because the
  50   // operating system may hold onto a reference to an AXNode
  51   // object even after we're through with it, so this may decrement the
  52   // reference count and clear out the object's data.
  53   void Destroy();
  54
  55   // Return true if this object is equal to or a descendant of |ancestor|.
  56   bool IsDescendantOf(AXNode* ancestor);
  57
  58  private:
  59   int index_in_parent_;
  60   AXNode* parent_;
  61   std::vector<AXNode*> children_;
  62   AXNodeData data_;
  63 };
  64
  65
  66 }  // namespace ui
  67
  68 #endif  // UI_ACCESSIBILITY_AX_NODE_H_