accessible/android/ProxyAccessibleWrap.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. *
   6  */
   7
   8 #ifndef MOZILLA_A11Y_ProxyAccessibleWrap_h
   9 #define MOZILLA_A11Y_ProxyAccessibleWrap_h
  10
  11 #include "AccessibleWrap.h"
  12 #include "DocAccessibleParent.h"
  13
  14 namespace mozilla {
  15 namespace a11y {
  16
  17 /**
  18  * A wrapper for Accessible proxies. The public methods here should be overriden
  19  * from AccessibleWrap or its super classes.
  20  * This gives us an abstraction layer so SessionAccessibility doesn't have
  21  * to distinguish between a local or remote accessibles.
  22  * NOTE: This shouldn't be regarded as a full Accessible implementation.
  23  */
  24 class ProxyAccessibleWrap : public AccessibleWrap {
  25  public:
  26   explicit ProxyAccessibleWrap(ProxyAccessible* aProxy);
  27
  28   virtual void Shutdown() override;
  29
  30   // Accessible
  31
  32   virtual already_AddRefed<nsIPersistentProperties> Attributes() override;
  33
  34   virtual uint32_t ChildCount() const override;
  35
  36   virtual Accessible* GetChildAt(uint32_t aIndex) const override;
  37
  38   virtual ENameValueFlag Name(nsString& aName) const override;
  39
  40   virtual void Value(nsString& aValue) const override;
  41
  42   virtual uint64_t State() override;
  43
  44   virtual nsIntRect Bounds() const override;
  45
  46   virtual void ScrollTo(uint32_t aHow) const override;
  47
  48   virtual uint8_t ActionCount() const override;
  49
  50   virtual bool DoAction(uint8_t aIndex) const override;
  51
  52   // AccessibleWrap
  53
  54   virtual void SetTextContents(const nsAString& aText) override;
  55
  56   virtual void GetTextContents(nsAString& aText) override;
  57
  58   virtual bool GetSelectionBounds(int32_t* aStartOffset,
  59                                   int32_t* aEndOffset) override;
  60
  61   virtual void WrapperDOMNodeID(nsString& aDOMNodeID) override;
  62
  63  private:
  64   virtual role WrapperRole() override;
  65
  66   virtual AccessibleWrap* WrapperParent() override;
  67
  68   virtual bool WrapperRangeInfo(double* aCurVal, double* aMinVal,
  69                                 double* aMaxVal, double* aStep) override;
  70 };
  71
  72 class DocProxyAccessibleWrap : public ProxyAccessibleWrap {
  73  public:
  74   explicit DocProxyAccessibleWrap(DocAccessibleParent* aProxy)
  75       : ProxyAccessibleWrap(aProxy) {
  76     mGenericTypes |= eDocument;
  77
  78     if (auto parent = ParentDocument()) {
  79       mID = AcquireID();
  80       parent->AddID(mID, this);
  81     } else {
  82       // top level
  83       mID = kNoID;
  84     }
  85   }
  86
  87   virtual void Shutdown() override {
  88     if (mID) {
  89       auto parent = ParentDocument();
  90       if (parent) {
  91         MOZ_ASSERT(mID != kNoID, "A non root accessible always has a parent");
  92         parent->RemoveID(mID);
  93         ReleaseID(mID);
  94       }
  95     }
  96     mID = 0;
  97     mBits.proxy = nullptr;
  98     mStateFlags |= eIsDefunct;
  99   }
 100
 101   DocProxyAccessibleWrap* ParentDocument() {
 102     DocAccessibleParent* proxy = static_cast<DocAccessibleParent*>(Proxy());
 103     MOZ_ASSERT(proxy);
 104     if (DocAccessibleParent* parent = proxy->ParentDoc()) {
 105       return reinterpret_cast<DocProxyAccessibleWrap*>(parent->GetWrapper());
 106     }
 107
 108     return nullptr;
 109   }
 110
 111   DocProxyAccessibleWrap* GetChildDocumentAt(uint32_t aIndex) {
 112     auto doc = Proxy()->AsDoc();
 113     if (doc && doc->ChildDocCount() > aIndex) {
 114       return reinterpret_cast<DocProxyAccessibleWrap*>(
 115           doc->ChildDocAt(aIndex)->GetWrapper());
 116     }
 117
 118     return nullptr;
 119   }
 120
 121   void AddID(uint32_t aID, AccessibleWrap* aAcc) {
 122     mIDToAccessibleMap.Put(aID, aAcc);
 123   }
 124   void RemoveID(uint32_t aID) { mIDToAccessibleMap.Remove(aID); }
 125   AccessibleWrap* GetAccessibleByID(uint32_t aID) const {
 126     return mIDToAccessibleMap.Get(aID);
 127   }
 128
 129  private:
 130   /*
 131    * This provides a mapping from 32 bit id to accessible objects.
 132    */
 133   nsDataHashtable<nsUint32HashKey, AccessibleWrap*> mIDToAccessibleMap;
 134 };
 135 }  // namespace a11y
 136 }  // namespace mozilla
 137
 138 #endif