content/browser/accessibility/browser_accessibility_win.cc

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/accessibility/browser_accessibility_win.h"

#include "content/browser/accessibility/browser_accessibility_manager.h"
#include "content/browser/accessibility/browser_accessibility_manager_win.h"
#include "content/browser/accessibility/browser_accessibility_state_impl.h"

#include "ui/base/win/atl_module.h"

namespace content {

// static
BrowserAccessibility* BrowserAccessibility::Create() {
  return new BrowserAccessibilityWin();
}

BrowserAccessibilityWin::BrowserAccessibilityWin() {
  ui::win::CreateATLModuleIfNeeded();
  HRESULT hr = CComObject<BrowserAccessibilityComWin>::CreateInstance(
      &browser_accessibility_com_);
  DCHECK(SUCCEEDED(hr));

  browser_accessibility_com_->AddRef();

  // Set the delegate to us
  browser_accessibility_com_->Init(this);
}

BrowserAccessibilityWin::~BrowserAccessibilityWin() {
  if (browser_accessibility_com_) {
    browser_accessibility_com_->Destroy();
    browser_accessibility_com_ = nullptr;
  }
}

void BrowserAccessibilityWin::UpdatePlatformAttributes() {
  GetCOM()->UpdateStep1ComputeWinAttributes();
  GetCOM()->UpdateStep2ComputeHypertext();
  GetCOM()->UpdateStep3FireEvents();
}

bool BrowserAccessibilityWin::CanFireEvents() const {
  // On Windows, we want to hide the subtree of a collapsed <select> element but
  // we still need to fire events on those hidden nodes.
  if (!IsIgnored() && GetCollapsedMenuListPopUpButtonAncestor())
    return true;

  // If the node changed its ignored state this frame then some events should be
  // allowed, such as hide/show/structure events. If a node with no siblings
  // changes aria-hidden value, this would affect whether it would be considered
  // a "child of leaf" node which affects BrowserAccessibility::CanFireEvents.
  if (manager()->ToBrowserAccessibilityManagerWin()->IsIgnoredChangedNode(this))
    return true;

  return BrowserAccessibility::CanFireEvents();
}

ui::AXPlatformNode* BrowserAccessibilityWin::GetAXPlatformNode() const {
  return GetCOM();
}

void BrowserAccessibilityWin::OnLocationChanged() {
  GetCOM()->FireNativeEvent(EVENT_OBJECT_LOCATIONCHANGE);
}

std::u16string BrowserAccessibilityWin::GetHypertext() const {
  return GetCOM()->AXPlatformNodeWin::GetHypertext();
}

const std::vector<gfx::NativeViewAccessible>
BrowserAccessibilityWin::GetUIADescendants() const {
  std::vector<gfx::NativeViewAccessible> descendants;
  if (!IsIgnored() && !ShouldHideChildrenForUIA() && PlatformChildCount() > 0) {
    BrowserAccessibility* next_sibling_node = PlatformGetNextSibling();
    BrowserAccessibility* next_descendant_node =
        BrowserAccessibilityManager::NextInTreeOrder(this);

    while (next_descendant_node && next_descendant_node != next_sibling_node) {
      // Don't add an ignored node to the returned descendants.
      if (!next_descendant_node->IsIgnored()) {
        descendants.emplace_back(
            next_descendant_node->GetNativeViewAccessible());

        if (!ToBrowserAccessibilityWin(next_descendant_node)
                 ->ShouldHideChildrenForUIA()) {
          next_descendant_node = BrowserAccessibilityManager::NextInTreeOrder(
              next_descendant_node);
          continue;
        }
      }
      // When a node is ignored or hides its children, don't return any of its
      // descendants.
      next_descendant_node =
          BrowserAccessibilityManager::NextNonDescendantInTreeOrder(
              next_descendant_node);
    }
  }
  return descendants;
}

gfx::NativeViewAccessible BrowserAccessibilityWin::GetNativeViewAccessible() {
  return GetCOM();
}

BrowserAccessibilityComWin* BrowserAccessibilityWin::GetCOM() const {
  DCHECK(browser_accessibility_com_);
  return browser_accessibility_com_;
}

BrowserAccessibilityWin* ToBrowserAccessibilityWin(BrowserAccessibility* obj) {
  return static_cast<BrowserAccessibilityWin*>(obj);
}

const BrowserAccessibilityWin* ToBrowserAccessibilityWin(
    const BrowserAccessibility* obj) {
  return static_cast<const BrowserAccessibilityWin*>(obj);
}

ui::TextAttributeList BrowserAccessibilityWin::ComputeTextAttributes() const {
  return GetCOM()->AXPlatformNodeWin::ComputeTextAttributes();
}

bool BrowserAccessibilityWin::ShouldHideChildrenForUIA() const {
  return GetCOM()->AXPlatformNodeWin::ShouldHideChildrenForUIA();
}

}  // namespace content