ui/accessibility/ax_serializable_tree.cc

   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 #include "ui/accessibility/ax_serializable_tree.h"
   6
   7 #include "ui/accessibility/ax_node.h"
   8
   9 namespace ui {
  10
  11 // This class is an implementation of the AXTreeSource interface with
  12 // AXNode as the node type, that just delegates to an AXTree. The purpose
  13 // of this is so that AXTreeSerializer only needs to work with the
  14 // AXTreeSource abstraction and doesn't need to actually know about
  15 // AXTree directly. Another AXTreeSource is used to abstract the Blink
  16 // accessibility tree.
  17 class AX_EXPORT AXTreeSourceAdapter : public AXTreeSource<const AXNode*> {
  18  public:
  19   AXTreeSourceAdapter(AXTree* tree) : tree_(tree) {}
  20   virtual ~AXTreeSourceAdapter() {}
  21
  22   // AXTreeSource implementation.
  23   virtual AXNode* GetRoot() const OVERRIDE {
  24     return tree_->GetRoot();
  25   }
  26
  27   virtual AXNode* GetFromId(int32 id) const OVERRIDE {
  28     return tree_->GetFromId(id);
  29   }
  30
  31   virtual int32 GetId(const AXNode* node) const OVERRIDE {
  32     return node->id();
  33   }
  34
  35   virtual void GetChildren(
  36       const AXNode* node,
  37       std::vector<const AXNode*>* out_children) const OVERRIDE {
  38     for (int i = 0; i < node->child_count(); ++i)
  39       out_children->push_back(node->ChildAtIndex(i));
  40   }
  41
  42   virtual AXNode* GetParent(const AXNode* node) const OVERRIDE {
  43     return node->parent();
  44   }
  45
  46   virtual bool IsValid(const AXNode* node) const OVERRIDE {
  47     return node != NULL;
  48   }
  49
  50   virtual bool IsEqual(const AXNode* node1,
  51                        const AXNode* node2) const OVERRIDE {
  52     return node1 == node2;
  53   }
  54
  55   virtual const AXNode* GetNull() const OVERRIDE {
  56     return NULL;
  57   }
  58
  59   virtual void SerializeNode(
  60       const AXNode* node, AXNodeData* out_data) const OVERRIDE {
  61     *out_data = node->data();
  62   }
  63
  64  private:
  65   AXTree* tree_;
  66 };
  67
  68 AXSerializableTree::AXSerializableTree()
  69     : AXTree() {}
  70
  71 AXSerializableTree::AXSerializableTree(const AXTreeUpdate& initial_state)
  72     : AXTree(initial_state) {
  73 }
  74
  75 AXSerializableTree::~AXSerializableTree() {
  76 }
  77
  78 AXTreeSource<const AXNode*>* AXSerializableTree::CreateTreeSource() {
  79   return new AXTreeSourceAdapter(this);
  80 }
  81
  82 }  // namespace ui