accessible/xul/XULComboboxAccessible.cpp
author Nicholas Nethercote <nnethercote@mozilla.com>
Fri, 19 Aug 2016 09:03:04 +1000
changeset 335989 6a81bba012c8d4283978ae3c6920843916817bfc
parent 308029 5e301a8b9efe2dfa0efc21b44d46e1a921a08610
permissions -rw-r--r--
Bug 1293596 (part 2) - Rework nsIWidget bounds getters. r=mstange. This patch makes GetBounds(), GetScreenBounds() and GetClientBounds() more obviously infallible, like existing functions such as GetNaturalBounds() and GetClientSize(). This results in clearer behaviour in nsCocoaWindow.mm if Objective C exceptions occur. Along the way, the patch removes some useless failure checks for these functions. The patch also removes the NS_IMETHOD from GetRestoredBounds and makes that function MOZ_MUST_USE.

/* -*- Mode: C++; tab-width: 4; 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 "XULComboboxAccessible.h"

#include "Accessible-inl.h"
#include "nsAccessibilityService.h"
#include "DocAccessible.h"
#include "nsCoreUtils.h"
#include "Role.h"
#include "States.h"

#include "nsIAutoCompleteInput.h"
#include "nsIDOMXULMenuListElement.h"
#include "nsIDOMXULSelectCntrlItemEl.h"

using namespace mozilla::a11y;

////////////////////////////////////////////////////////////////////////////////
// XULComboboxAccessible
////////////////////////////////////////////////////////////////////////////////

XULComboboxAccessible::
  XULComboboxAccessible(nsIContent* aContent, DocAccessible* aDoc) :
  AccessibleWrap(aContent, aDoc)
{
  if (mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::type,
                            nsGkAtoms::autocomplete, eIgnoreCase))
    mGenericTypes |= eAutoComplete;
  else
    mGenericTypes |= eCombobox;

  // Both the XUL <textbox type="autocomplete"> and <menulist editable="true">
  // widgets use XULComboboxAccessible. We need to walk the anonymous children
  // for these so that the entry field is a child. Otherwise no XBL children.
  if (!mContent->NodeInfo()->Equals(nsGkAtoms::textbox, kNameSpaceID_XUL) &&
      !mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::editable,
                             nsGkAtoms::_true, eIgnoreCase)) {
    mStateFlags |= eNoXBLKids;
  }
}

role
XULComboboxAccessible::NativeRole()
{
  return IsAutoComplete() ? roles::AUTOCOMPLETE : roles::COMBOBOX;
}

uint64_t
XULComboboxAccessible::NativeState()
{
  // As a nsComboboxAccessible we can have the following states:
  //     STATE_FOCUSED
  //     STATE_FOCUSABLE
  //     STATE_HASPOPUP
  //     STATE_EXPANDED
  //     STATE_COLLAPSED

  // Get focus status from base class
  uint64_t state = Accessible::NativeState();

  nsCOMPtr<nsIDOMXULMenuListElement> menuList(do_QueryInterface(mContent));
  if (menuList) {
    bool isOpen = false;
    menuList->GetOpen(&isOpen);
    if (isOpen)
      state |= states::EXPANDED;
    else
      state |= states::COLLAPSED;
  }

  return state | states::HASPOPUP;
}

void
XULComboboxAccessible::Description(nsString& aDescription)
{
  aDescription.Truncate();
  // Use description of currently focused option
  nsCOMPtr<nsIDOMXULMenuListElement> menuListElm(do_QueryInterface(mContent));
  if (!menuListElm)
    return;

  nsCOMPtr<nsIDOMXULSelectControlItemElement> focusedOptionItem;
  menuListElm->GetSelectedItem(getter_AddRefs(focusedOptionItem));
  nsCOMPtr<nsIContent> focusedOptionContent =
    do_QueryInterface(focusedOptionItem);
  if (focusedOptionContent && mDoc) {
    Accessible* focusedOptionAcc = mDoc->GetAccessible(focusedOptionContent);
    if (focusedOptionAcc)
      focusedOptionAcc->Description(aDescription);
  }
}

void
XULComboboxAccessible::Value(nsString& aValue)
{
  aValue.Truncate();

  // The value is the option or text shown entered in the combobox.
  nsCOMPtr<nsIDOMXULMenuListElement> menuList(do_QueryInterface(mContent));
  if (menuList)
    menuList->GetLabel(aValue);
}

uint8_t
XULComboboxAccessible::ActionCount()
{
  // Just one action (click).
  return 1;
}

bool
XULComboboxAccessible::DoAction(uint8_t aIndex)
{
  if (aIndex != XULComboboxAccessible::eAction_Click)
    return false;

  // Programmaticaly toggle the combo box.
  nsCOMPtr<nsIDOMXULMenuListElement> menuList(do_QueryInterface(mContent));
  if (!menuList)
    return false;

  bool isDroppedDown = false;
  menuList->GetOpen(&isDroppedDown);
  menuList->SetOpen(!isDroppedDown);
  return true;
}

void
XULComboboxAccessible::ActionNameAt(uint8_t aIndex, nsAString& aName)
{
  aName.Truncate();
  if (aIndex != XULComboboxAccessible::eAction_Click)
    return;

  nsCOMPtr<nsIDOMXULMenuListElement> menuList(do_QueryInterface(mContent));
  if (!menuList)
    return;

  bool isDroppedDown = false;
  menuList->GetOpen(&isDroppedDown);
  if (isDroppedDown)
    aName.AssignLiteral("close");
  else
    aName.AssignLiteral("open");
}

////////////////////////////////////////////////////////////////////////////////
// Widgets

bool
XULComboboxAccessible::IsActiveWidget() const
{
  if (IsAutoComplete() ||
     mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::editable,
                           nsGkAtoms::_true, eIgnoreCase)) {
    int32_t childCount = mChildren.Length();
    for (int32_t idx = 0; idx < childCount; idx++) {
      Accessible* child = mChildren[idx];
      if (child->Role() == roles::ENTRY)
        return FocusMgr()->HasDOMFocus(child->GetContent());
    }
    return false;
  }

  return FocusMgr()->HasDOMFocus(mContent);
}

bool
XULComboboxAccessible::AreItemsOperable() const
{
  if (IsAutoComplete()) {
    nsCOMPtr<nsIAutoCompleteInput> autoCompleteInputElm =
      do_QueryInterface(mContent);
    if (autoCompleteInputElm) {
      bool isOpen = false;
      autoCompleteInputElm->GetPopupOpen(&isOpen);
      return isOpen;
    }
    return false;
  }

  nsCOMPtr<nsIDOMXULMenuListElement> menuListElm = do_QueryInterface(mContent);
  if (menuListElm) {
    bool isOpen = false;
    menuListElm->GetOpen(&isOpen);
    return isOpen;
  }

  return false;
}