accessible/windows/msaa/HTMLWin32ObjectAccessible.cpp
author Alexander Surkov <surkov.alexander@gmail.com>
Thu, 31 Mar 2016 21:23:03 -0400
changeset 291172 2724b036ed2b3a3bab2987a563ccc7fc64488618
parent 211666 ef5d07a500fdb98ce847a637bc50f65174a599cc
child 291176 8af4e6b9642767e130a8e30ce15d84d93b8eacaf
permissions -rw-r--r--
Bug 1258228 - create special child accessibles in owner's constructor, part4, r=marcoz

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "HTMLWin32ObjectAccessible.h"

#include "Role.h"
#include "States.h"

using namespace mozilla::a11y;

////////////////////////////////////////////////////////////////////////////////
// HTMLWin32ObjectOwnerAccessible
////////////////////////////////////////////////////////////////////////////////

HTMLWin32ObjectOwnerAccessible::
  HTMLWin32ObjectOwnerAccessible(nsIContent* aContent,
                                 DocAccessible* aDoc, void* aHwnd) :
  AccessibleWrap(aContent, aDoc), mHwnd(aHwnd)
{
  // Our only child is a HTMLWin32ObjectAccessible object.
  if (mHwnd) {
    mNativeAccessible = new HTMLWin32ObjectAccessible(mHwnd, aDoc);
    AppendChild(mNativeAccessible);
  }
}

////////////////////////////////////////////////////////////////////////////////
// HTMLWin32ObjectOwnerAccessible: Accessible implementation

void
HTMLWin32ObjectOwnerAccessible::Shutdown()
{
  AccessibleWrap::Shutdown();
  mNativeAccessible = nullptr;
}

role
HTMLWin32ObjectOwnerAccessible::NativeRole()
{
  return roles::EMBEDDED_OBJECT;
}

bool
HTMLWin32ObjectOwnerAccessible::NativelyUnavailable() const
{
  // XXX: No HWND means this is windowless plugin which is not accessible in
  // the meantime.
  return !mHwnd;
}

////////////////////////////////////////////////////////////////////////////////
// HTMLWin32ObjectOwnerAccessible: Accessible protected implementation

void
HTMLWin32ObjectOwnerAccessible::CacheChildren()
{
}


////////////////////////////////////////////////////////////////////////////////
// HTMLWin32ObjectAccessible
////////////////////////////////////////////////////////////////////////////////

HTMLWin32ObjectAccessible::HTMLWin32ObjectAccessible(void* aHwnd,
                                                     DocAccessible* aDoc) :
  DummyAccessible(aDoc)
{
  mHwnd = aHwnd;
  if (mHwnd) {
    // The plugin is not windowless. In this situation we use 
    // use its inner child owned by the plugin so that we don't get
    // in an infinite loop, where the WM_GETOBJECT's get forwarded
    // back to us and create another HTMLWin32ObjectAccessible
    HWND childWnd = ::GetWindow((HWND)aHwnd, GW_CHILD);
    if (childWnd) {
      mHwnd = childWnd;
    }
  }
}

void
HTMLWin32ObjectAccessible::GetNativeInterface(void** aNativeAccessible)
{
  if (mHwnd) {
    ::AccessibleObjectFromWindow(static_cast<HWND>(mHwnd),
                                 OBJID_WINDOW, IID_IAccessible,
                                 aNativeAccessible);
  }
}