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 <vector>
   9
  10 #include "ui/accessibility/ax_node_data.h"
  11
  12 namespace gfx {
  13 class Rect;
  14 }
  15
  16 namespace ui {
  17
  18 // One node in an AXTree.
  19 class AX_EXPORT AXNode {
  20  public:
  21   // The constructor requires a parent, id, and index in parent, but
  22   // the data is not required. After initialization, only index_in_parent
  23   // is allowed to change, the others are guaranteed to never change.
  24   AXNode(AXNode* parent, int32 id, int32 index_in_parent);
  25   virtual ~AXNode();
  26
  27   // Accessors.
  28   int32 id() const { return data_.id; }
  29   AXNode* parent() const { return parent_; }
  30   int child_count() const { return static_cast<int>(children_.size()); }
  31   const AXNodeData& data() const { return data_; }
  32   const std::vector<AXNode*>& children() const { return children_; }
  33   int index_in_parent() const { return index_in_parent_; }
  34
  35   // Get the child at the given index.
  36   AXNode* ChildAtIndex(int index) const { return children_[index]; }
  37
  38   // Set the node's accessibility data. This may be done during initial
  39   // initialization or later when the node data changes.
  40   void SetData(const AXNodeData& src);
  41
  42   // Update this node's location. This is separate from SetData just because
  43   // changing only the location is common and should be more efficient than
  44   // re-copying all of the data.
  45   void SetLocation(const gfx::Rect& new_location);
  46
  47   // Set the index in parent, for example if siblings were inserted or deleted.
  48   void SetIndexInParent(int index_in_parent);
  49
  50   // Swap the internal children vector with |children|. This instance
  51   // now owns all of the passed children.
  52   void SwapChildren(std::vector<AXNode*>& children);
  53
  54   // This is called when the AXTree no longer includes this node in the
  55   // tree. Reference counting is used on some platforms because the
  56   // operating system may hold onto a reference to an AXNode
  57   // object even after we're through with it, so this may decrement the
  58   // reference count and clear out the object's data.
  59   void Destroy();
  60
  61   // Return true if this object is equal to or a descendant of |ancestor|.
  62   bool IsDescendantOf(AXNode* ancestor);
  63
  64  private:
  65   int index_in_parent_;
  66   AXNode* parent_;
  67   std::vector<AXNode*> children_;
  68   AXNodeData data_;
  69 };
  70
  71 }  // namespace ui
  72
  73 #endif  // UI_ACCESSIBILITY_AX_NODE_H_