gecko-dev/accessible/windows/msaa/AccessibleWrap.cpp

1678 строки
41 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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 "AccessibleWrap.h"
#include "Accessible-inl.h"
#include "Compatibility.h"
#include "DocAccessible-inl.h"
#include "mozilla/a11y/DocAccessibleParent.h"
#include "EnumVariant.h"
#include "nsAccUtils.h"
#include "nsCoreUtils.h"
#include "nsIAccessibleEvent.h"
#include "nsWinUtils.h"
#include "mozilla/a11y/ProxyAccessible.h"
#include "ProxyWrappers.h"
#include "ServiceProvider.h"
#include "Relation.h"
#include "Role.h"
#include "RootAccessible.h"
#include "sdnAccessible.h"
#include "States.h"
#ifdef A11Y_LOG
#include "Logging.h"
#endif
#include "nsIMutableArray.h"
#include "nsIFrame.h"
#include "nsIScrollableFrame.h"
#include "mozilla/dom/NodeInfo.h"
#include "nsIServiceManager.h"
#include "nsNameSpaceManager.h"
#include "nsTextFormatter.h"
#include "nsView.h"
#include "nsViewManager.h"
#include "nsEventMap.h"
#include "nsArrayUtils.h"
#include "mozilla/Preferences.h"
#include "oleacc.h"
using namespace mozilla;
using namespace mozilla::a11y;
const uint32_t USE_ROLE_STRING = 0;
/* For documentation of the accessibility architecture,
* see http://lxr.mozilla.org/seamonkey/source/accessible/accessible-docs.html
*/
//#define DEBUG_LEAKS
#ifdef DEBUG_LEAKS
static gAccessibles = 0;
#endif
#ifdef _WIN64
IDSet AccessibleWrap::sIDGen;
#endif
static const int32_t kIEnumVariantDisconnected = -1;
////////////////////////////////////////////////////////////////////////////////
// AccessibleWrap
////////////////////////////////////////////////////////////////////////////////
AccessibleWrap::AccessibleWrap(nsIContent* aContent, DocAccessible* aDoc) :
Accessible(aContent, aDoc)
#ifdef _WIN64
, mID(kNoID)
#endif
{
}
AccessibleWrap::~AccessibleWrap()
{
#ifdef _WIN64
if (mID != kNoID)
sIDGen.ReleaseID(mID);
#endif
}
ITypeInfo* AccessibleWrap::gTypeInfo = nullptr;
NS_IMPL_ISUPPORTS_INHERITED0(AccessibleWrap, Accessible)
void
AccessibleWrap::Shutdown()
{
#ifdef _WIN64
if (mID != kNoID) {
auto doc = static_cast<DocAccessibleWrap*>(mDoc);
MOZ_ASSERT(doc);
if (doc) {
doc->RemoveID(mID);
}
}
#endif
Accessible::Shutdown();
}
//-----------------------------------------------------
// IUnknown interface methods - see iunknown.h for documentation
//-----------------------------------------------------
// Microsoft COM QueryInterface
STDMETHODIMP
AccessibleWrap::QueryInterface(REFIID iid, void** ppv)
{
A11Y_TRYBLOCK_BEGIN
if (!ppv)
return E_INVALIDARG;
*ppv = nullptr;
if (IID_IUnknown == iid)
*ppv = static_cast<IAccessible*>(this);
else if (IID_IDispatch == iid || IID_IAccessible == iid)
*ppv = static_cast<IAccessible*>(this);
else if (IID_IEnumVARIANT == iid && !IsProxy()) {
// Don't support this interface for leaf elements.
if (!HasChildren() || nsAccUtils::MustPrune(this))
return E_NOINTERFACE;
*ppv = static_cast<IEnumVARIANT*>(new ChildrenEnumVariant(this));
} else if (IID_IServiceProvider == iid)
*ppv = new ServiceProvider(this);
else if (IID_ISimpleDOMNode == iid && !IsProxy()) {
if (IsDefunct() || (!HasOwnContent() && !IsDoc()))
return E_NOINTERFACE;
*ppv = static_cast<ISimpleDOMNode*>(new sdnAccessible(GetNode()));
}
if (nullptr == *ppv) {
HRESULT hr = ia2Accessible::QueryInterface(iid, ppv);
if (SUCCEEDED(hr))
return hr;
}
if (nullptr == *ppv && !IsProxy()) {
HRESULT hr = ia2AccessibleComponent::QueryInterface(iid, ppv);
if (SUCCEEDED(hr))
return hr;
}
if (nullptr == *ppv) {
HRESULT hr = ia2AccessibleHyperlink::QueryInterface(iid, ppv);
if (SUCCEEDED(hr))
return hr;
}
if (nullptr == *ppv && !IsProxy()) {
HRESULT hr = ia2AccessibleValue::QueryInterface(iid, ppv);
if (SUCCEEDED(hr))
return hr;
}
if (nullptr == *ppv)
return E_NOINTERFACE;
(reinterpret_cast<IUnknown*>(*ppv))->AddRef();
return S_OK;
A11Y_TRYBLOCK_END
}
//-----------------------------------------------------
// IAccessible methods
//-----------------------------------------------------
STDMETHODIMP
AccessibleWrap::get_accParent( IDispatch __RPC_FAR *__RPC_FAR *ppdispParent)
{
A11Y_TRYBLOCK_BEGIN
if (!ppdispParent)
return E_INVALIDARG;
*ppdispParent = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
if (IsProxy()) {
ProxyAccessible* proxy = Proxy();
ProxyAccessible* parent = proxy->Parent();
if (!parent)
return S_FALSE;
*ppdispParent = NativeAccessible(WrapperFor(parent));
return S_OK;
}
DocAccessible* doc = AsDoc();
if (doc) {
// Return window system accessible object for root document and tab document
// accessibles.
if (!doc->ParentDocument() ||
(nsWinUtils::IsWindowEmulationStarted() &&
nsCoreUtils::IsTabDocument(doc->DocumentNode()))) {
HWND hwnd = static_cast<HWND>(doc->GetNativeWindow());
if (hwnd && SUCCEEDED(::AccessibleObjectFromWindow(hwnd, OBJID_WINDOW,
IID_IAccessible,
(void**)ppdispParent))) {
return S_OK;
}
}
}
Accessible* xpParentAcc = Parent();
if (!xpParentAcc)
return S_FALSE;
*ppdispParent = NativeAccessible(xpParentAcc);
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accChildCount( long __RPC_FAR *pcountChildren)
{
A11Y_TRYBLOCK_BEGIN
if (!pcountChildren)
return E_INVALIDARG;
*pcountChildren = 0;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
if (IsProxy()) {
ProxyAccessible* proxy = Proxy();
if (proxy->MustPruneChildren())
return S_OK;
*pcountChildren = proxy->ChildrenCount();
return S_OK;
}
if (nsAccUtils::MustPrune(this))
return S_OK;
*pcountChildren = ChildCount();
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accChild(
/* [in] */ VARIANT varChild,
/* [retval][out] */ IDispatch __RPC_FAR *__RPC_FAR *ppdispChild)
{
A11Y_TRYBLOCK_BEGIN
if (!ppdispChild)
return E_INVALIDARG;
*ppdispChild = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
// IAccessible::accChild is used to return this accessible or child accessible
// at the given index or to get an accessible by child ID in the case of
// document accessible (it's handled by overriden GetXPAccessibleFor method
// on the document accessible). The getting an accessible by child ID is used
// by AccessibleObjectFromEvent() called by AT when AT handles our MSAA event.
Accessible* child = GetXPAccessibleFor(varChild);
if (!child)
return E_INVALIDARG;
if (child->IsDefunct())
return CO_E_OBJNOTCONNECTED;
*ppdispChild = NativeAccessible(child);
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accName(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ BSTR __RPC_FAR *pszName)
{
A11Y_TRYBLOCK_BEGIN
if (!pszName)
return E_INVALIDARG;
*pszName = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
nsAutoString name;
if (xpAccessible->IsProxy())
xpAccessible->Proxy()->Name(name);
else
xpAccessible->Name(name);
// The name was not provided, e.g. no alt attribute for an image. A screen
// reader may choose to invent its own accessible name, e.g. from an image src
// attribute. Refer to eNoNameOnPurpose return value.
if (name.IsVoid())
return S_FALSE;
*pszName = ::SysAllocStringLen(name.get(), name.Length());
if (!*pszName)
return E_OUTOFMEMORY;
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accValue(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ BSTR __RPC_FAR *pszValue)
{
A11Y_TRYBLOCK_BEGIN
if (!pszValue)
return E_INVALIDARG;
*pszValue = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
// TODO make this work with proxies.
if (IsProxy())
return E_NOTIMPL;
nsAutoString value;
xpAccessible->Value(value);
// See bug 438784: need to expose URL on doc's value attribute. For this,
// reverting part of fix for bug 425693 to make this MSAA method behave
// IAccessible2-style.
if (value.IsEmpty())
return S_FALSE;
*pszValue = ::SysAllocStringLen(value.get(), value.Length());
if (!*pszValue)
return E_OUTOFMEMORY;
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accDescription(VARIANT varChild,
BSTR __RPC_FAR *pszDescription)
{
A11Y_TRYBLOCK_BEGIN
if (!pszDescription)
return E_INVALIDARG;
*pszDescription = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
nsAutoString description;
if (IsProxy())
xpAccessible->Proxy()->Description(description);
else
xpAccessible->Description(description);
*pszDescription = ::SysAllocStringLen(description.get(),
description.Length());
return *pszDescription ? S_OK : E_OUTOFMEMORY;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accRole(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ VARIANT __RPC_FAR *pvarRole)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarRole)
return E_INVALIDARG;
VariantInit(pvarRole);
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
a11y::role geckoRole;
if (xpAccessible->IsProxy()) {
geckoRole = xpAccessible->Proxy()->Role();
} else {
#ifdef DEBUG
NS_ASSERTION(nsAccUtils::IsTextInterfaceSupportCorrect(xpAccessible),
"Does not support Text when it should");
#endif
geckoRole = xpAccessible->Role();
}
uint32_t msaaRole = 0;
#define ROLE(_geckoRole, stringRole, atkRole, macRole, \
_msaaRole, ia2Role, nameRule) \
case roles::_geckoRole: \
msaaRole = _msaaRole; \
break;
switch (geckoRole) {
#include "RoleMap.h"
default:
MOZ_CRASH("Unknown role.");
}
#undef ROLE
// Special case, if there is a ROLE_ROW inside of a ROLE_TREE_TABLE, then call the MSAA role
// a ROLE_OUTLINEITEM for consistency and compatibility.
// We need this because ARIA has a role of "row" for both grid and treegrid
if (xpAccessible->IsProxy()) {
if (geckoRole == roles::ROW
&& xpAccessible->Proxy()->Parent()->Role() == roles::TREE_TABLE)
msaaRole = ROLE_SYSTEM_OUTLINEITEM;
} else {
if (geckoRole == roles::ROW) {
Accessible* xpParent = Parent();
if (xpParent && xpParent->Role() == roles::TREE_TABLE)
msaaRole = ROLE_SYSTEM_OUTLINEITEM;
}
}
// -- Try enumerated role
if (msaaRole != USE_ROLE_STRING) {
pvarRole->vt = VT_I4;
pvarRole->lVal = msaaRole; // Normal enumerated role
return S_OK;
}
// XXX bug 798492 make this work with proxies?
if (IsProxy())
return E_FAIL;
// -- Try BSTR role
// Could not map to known enumerated MSAA role like ROLE_BUTTON
// Use BSTR role to expose role attribute or tag name + namespace
nsIContent *content = xpAccessible->GetContent();
if (!content)
return E_FAIL;
if (content->IsElement()) {
nsAutoString roleString;
if (msaaRole != ROLE_SYSTEM_CLIENT &&
!content->GetAttr(kNameSpaceID_None, nsGkAtoms::role, roleString)) {
nsIDocument * document = content->GetCurrentDoc();
if (!document)
return E_FAIL;
dom::NodeInfo *nodeInfo = content->NodeInfo();
nodeInfo->GetName(roleString);
// Only append name space if different from that of current document.
if (!nodeInfo->NamespaceEquals(document->GetDefaultNamespaceID())) {
nsAutoString nameSpaceURI;
nodeInfo->GetNamespaceURI(nameSpaceURI);
roleString += NS_LITERAL_STRING(", ") + nameSpaceURI;
}
}
if (!roleString.IsEmpty()) {
pvarRole->vt = VT_BSTR;
pvarRole->bstrVal = ::SysAllocString(roleString.get());
return S_OK;
}
}
return E_FAIL;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accState(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ VARIANT __RPC_FAR *pvarState)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarState)
return E_INVALIDARG;
VariantInit(pvarState);
pvarState->vt = VT_I4;
pvarState->lVal = 0;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
// MSAA only has 31 states and the lowest 31 bits of our state bit mask
// are the same states as MSAA.
// Note: we map the following Gecko states to different MSAA states:
// REQUIRED -> ALERT_LOW
// ALERT -> ALERT_MEDIUM
// INVALID -> ALERT_HIGH
// CHECKABLE -> MARQUEED
uint64_t state;
if (xpAccessible->IsProxy())
state = xpAccessible->Proxy()->State();
else
state = State();
uint32_t msaaState = 0;
nsAccUtils::To32States(state, &msaaState, nullptr);
pvarState->lVal = msaaState;
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accHelp(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ BSTR __RPC_FAR *pszHelp)
{
A11Y_TRYBLOCK_BEGIN
if (!pszHelp)
return E_INVALIDARG;
*pszHelp = nullptr;
return S_FALSE;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accHelpTopic(
/* [out] */ BSTR __RPC_FAR *pszHelpFile,
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ long __RPC_FAR *pidTopic)
{
A11Y_TRYBLOCK_BEGIN
if (!pszHelpFile || !pidTopic)
return E_INVALIDARG;
*pszHelpFile = nullptr;
*pidTopic = 0;
return S_FALSE;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accKeyboardShortcut(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ BSTR __RPC_FAR *pszKeyboardShortcut)
{
A11Y_TRYBLOCK_BEGIN
if (!pszKeyboardShortcut)
return E_INVALIDARG;
*pszKeyboardShortcut = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* acc = GetXPAccessibleFor(varChild);
if (!acc)
return E_INVALIDARG;
if (acc->IsDefunct())
return CO_E_OBJNOTCONNECTED;
// TODO make this work with proxies.
if (acc->IsProxy())
return E_NOTIMPL;
KeyBinding keyBinding = acc->AccessKey();
if (keyBinding.IsEmpty())
keyBinding = acc->KeyboardShortcut();
nsAutoString shortcut;
keyBinding.ToString(shortcut);
*pszKeyboardShortcut = ::SysAllocStringLen(shortcut.get(),
shortcut.Length());
return *pszKeyboardShortcut ? S_OK : E_OUTOFMEMORY;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accFocus(
/* [retval][out] */ VARIANT __RPC_FAR *pvarChild)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarChild)
return E_INVALIDARG;
VariantInit(pvarChild);
// VT_EMPTY: None. This object does not have the keyboard focus itself
// and does not contain a child that has the keyboard focus.
// VT_I4: lVal is CHILDID_SELF. The object itself has the keyboard focus.
// VT_I4: lVal contains the child ID of the child element with the keyboard focus.
// VT_DISPATCH: pdispVal member is the address of the IDispatch interface
// for the child object with the keyboard focus.
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
// Return the current IAccessible child that has focus
Accessible* focusedAccessible;
if (IsProxy()) {
ProxyAccessible* proxy = Proxy()->FocusedChild();
focusedAccessible = proxy ? WrapperFor(proxy) : nullptr;
} else {
focusedAccessible = FocusedChild();
}
if (focusedAccessible == this) {
pvarChild->vt = VT_I4;
pvarChild->lVal = CHILDID_SELF;
}
else if (focusedAccessible) {
pvarChild->vt = VT_DISPATCH;
pvarChild->pdispVal = NativeAccessible(focusedAccessible);
}
else {
pvarChild->vt = VT_EMPTY; // No focus or focus is not a child
}
return S_OK;
A11Y_TRYBLOCK_END
}
/**
* This helper class implements IEnumVARIANT for a nsTArray containing
* accessible objects.
*/
class AccessibleEnumerator final : public IEnumVARIANT
{
public:
AccessibleEnumerator(const nsTArray<Accessible*>& aArray) :
mArray(aArray), mCurIndex(0) { }
AccessibleEnumerator(const AccessibleEnumerator& toCopy) :
mArray(toCopy.mArray), mCurIndex(toCopy.mCurIndex) { }
~AccessibleEnumerator() { }
// IUnknown
DECL_IUNKNOWN
// IEnumVARIANT
STDMETHODIMP Next(unsigned long celt, VARIANT FAR* rgvar, unsigned long FAR* pceltFetched);
STDMETHODIMP Skip(unsigned long celt);
STDMETHODIMP Reset()
{
mCurIndex = 0;
return S_OK;
}
STDMETHODIMP Clone(IEnumVARIANT FAR* FAR* ppenum);
private:
nsTArray<Accessible*> mArray;
uint32_t mCurIndex;
};
STDMETHODIMP
AccessibleEnumerator::QueryInterface(REFIID iid, void ** ppvObject)
{
A11Y_TRYBLOCK_BEGIN
if (iid == IID_IEnumVARIANT) {
*ppvObject = static_cast<IEnumVARIANT*>(this);
AddRef();
return S_OK;
}
if (iid == IID_IUnknown) {
*ppvObject = static_cast<IUnknown*>(this);
AddRef();
return S_OK;
}
*ppvObject = nullptr;
return E_NOINTERFACE;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleEnumerator::Next(unsigned long celt, VARIANT FAR* rgvar, unsigned long FAR* pceltFetched)
{
A11Y_TRYBLOCK_BEGIN
uint32_t length = mArray.Length();
HRESULT hr = S_OK;
// Can't get more elements than there are...
if (celt > length - mCurIndex) {
hr = S_FALSE;
celt = length - mCurIndex;
}
// Copy the elements of the array into rgvar.
for (uint32_t i = 0; i < celt; ++i, ++mCurIndex) {
rgvar[i].vt = VT_DISPATCH;
rgvar[i].pdispVal = AccessibleWrap::NativeAccessible(mArray[mCurIndex]);
}
if (pceltFetched)
*pceltFetched = celt;
return hr;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleEnumerator::Clone(IEnumVARIANT FAR* FAR* ppenum)
{
A11Y_TRYBLOCK_BEGIN
*ppenum = new AccessibleEnumerator(*this);
if (!*ppenum)
return E_OUTOFMEMORY;
NS_ADDREF(*ppenum);
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleEnumerator::Skip(unsigned long celt)
{
A11Y_TRYBLOCK_BEGIN
uint32_t length = mArray.Length();
// Check if we can skip the requested number of elements
if (celt > length - mCurIndex) {
mCurIndex = length;
return S_FALSE;
}
mCurIndex += celt;
return S_OK;
A11Y_TRYBLOCK_END
}
/**
* This method is called when a client wants to know which children of a node
* are selected. Note that this method can only find selected children for
* accessible object which implement SelectAccessible.
*
* The VARIANT return value arguement is expected to either contain a single IAccessible
* or an IEnumVARIANT of IAccessibles. We return the IEnumVARIANT regardless of the number
* of children selected, unless there are none selected in which case we return an empty
* VARIANT.
*
* We get the selected options from the select's accessible object and wrap
* those in an AccessibleEnumerator which we then put in the return VARIANT.
*
* returns a VT_EMPTY VARIANT if:
* - there are no selected children for this object
* - the object is not the type that can have children selected
*/
STDMETHODIMP
AccessibleWrap::get_accSelection(VARIANT __RPC_FAR *pvarChildren)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarChildren)
return E_INVALIDARG;
VariantInit(pvarChildren);
pvarChildren->vt = VT_EMPTY;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
// TODO make this work with proxies.
if (IsProxy())
return E_NOTIMPL;
if (IsSelect()) {
AutoTArray<Accessible*, 10> selectedItems;
if (IsProxy()) {
nsTArray<ProxyAccessible*> proxies;
Proxy()->SelectedItems(&proxies);
uint32_t selectedCount = proxies.Length();
for (uint32_t i = 0; i < selectedCount; i++) {
selectedItems.AppendElement(WrapperFor(proxies[i]));
}
} else {
SelectedItems(&selectedItems);
}
// 1) Create and initialize the enumeration
RefPtr<AccessibleEnumerator> pEnum = new AccessibleEnumerator(selectedItems);
pvarChildren->vt = VT_UNKNOWN; // this must be VT_UNKNOWN for an IEnumVARIANT
NS_ADDREF(pvarChildren->punkVal = pEnum);
}
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::get_accDefaultAction(
/* [optional][in] */ VARIANT varChild,
/* [retval][out] */ BSTR __RPC_FAR *pszDefaultAction)
{
A11Y_TRYBLOCK_BEGIN
if (!pszDefaultAction)
return E_INVALIDARG;
*pszDefaultAction = nullptr;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
nsAutoString defaultAction;
if (xpAccessible->IsProxy()) {
xpAccessible->Proxy()->ActionNameAt(0, defaultAction);
} else {
xpAccessible->ActionNameAt(0, defaultAction);
}
*pszDefaultAction = ::SysAllocStringLen(defaultAction.get(),
defaultAction.Length());
return *pszDefaultAction ? S_OK : E_OUTOFMEMORY;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::accSelect(
/* [in] */ long flagsSelect,
/* [optional][in] */ VARIANT varChild)
{
A11Y_TRYBLOCK_BEGIN
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
// currently only handle focus and selection
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
if (flagsSelect & SELFLAG_TAKEFOCUS) {
if (xpAccessible->IsProxy()) {
xpAccessible->Proxy()->TakeFocus();
} else {
xpAccessible->TakeFocus();
}
return S_OK;
}
if (flagsSelect & SELFLAG_TAKESELECTION) {
if (xpAccessible->IsProxy()) {
xpAccessible->Proxy()->TakeSelection();
} else {
xpAccessible->TakeSelection();
}
return S_OK;
}
if (flagsSelect & SELFLAG_ADDSELECTION) {
if (xpAccessible->IsProxy()) {
xpAccessible->Proxy()->SetSelected(true);
} else {
xpAccessible->SetSelected(true);
}
return S_OK;
}
if (flagsSelect & SELFLAG_REMOVESELECTION) {
if (xpAccessible->IsProxy()) {
xpAccessible->Proxy()->SetSelected(false);
} else {
xpAccessible->SetSelected(false);
}
return S_OK;
}
return E_FAIL;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::accLocation(
/* [out] */ long __RPC_FAR *pxLeft,
/* [out] */ long __RPC_FAR *pyTop,
/* [out] */ long __RPC_FAR *pcxWidth,
/* [out] */ long __RPC_FAR *pcyHeight,
/* [optional][in] */ VARIANT varChild)
{
A11Y_TRYBLOCK_BEGIN
if (!pxLeft || !pyTop || !pcxWidth || !pcyHeight)
return E_INVALIDARG;
*pxLeft = 0;
*pyTop = 0;
*pcxWidth = 0;
*pcyHeight = 0;
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
nsIntRect rect;
if (xpAccessible->IsProxy()) {
rect = xpAccessible->Proxy()->Bounds();
} else {
rect = xpAccessible->Bounds();
}
*pxLeft = rect.x;
*pyTop = rect.y;
*pcxWidth = rect.width;
*pcyHeight = rect.height;
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::accNavigate(
/* [in] */ long navDir,
/* [optional][in] */ VARIANT varStart,
/* [retval][out] */ VARIANT __RPC_FAR *pvarEndUpAt)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarEndUpAt)
return E_INVALIDARG;
VariantInit(pvarEndUpAt);
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* accessible = GetXPAccessibleFor(varStart);
if (!accessible)
return E_INVALIDARG;
if (accessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* navAccessible = nullptr;
Maybe<RelationType> xpRelation;
#define RELATIONTYPE(geckoType, stringType, atkType, msaaType, ia2Type) \
case msaaType: \
xpRelation.emplace(RelationType::geckoType); \
break;
switch(navDir) {
case NAVDIR_FIRSTCHILD:
if (accessible->IsProxy()) {
if (!accessible->Proxy()->MustPruneChildren()) {
navAccessible = WrapperFor(accessible->Proxy()->FirstChild());
}
} else {
if (!nsAccUtils::MustPrune(accessible))
navAccessible = accessible->FirstChild();
}
break;
case NAVDIR_LASTCHILD:
if (accessible->IsProxy()) {
if (!accessible->Proxy()->MustPruneChildren()) {
navAccessible = WrapperFor(accessible->Proxy()->LastChild());
}
} else {
if (!nsAccUtils::MustPrune(accessible))
navAccessible = accessible->LastChild();
}
break;
case NAVDIR_NEXT:
navAccessible = accessible->IsProxy()
? WrapperFor(accessible->Proxy()->NextSibling())
: accessible->NextSibling();
break;
case NAVDIR_PREVIOUS:
navAccessible = accessible->IsProxy()
? WrapperFor(accessible->Proxy()->PrevSibling())
: accessible->PrevSibling();
break;
case NAVDIR_DOWN:
case NAVDIR_LEFT:
case NAVDIR_RIGHT:
case NAVDIR_UP:
return E_NOTIMPL;
// MSAA relationship extensions to accNavigate
#include "RelationTypeMap.h"
default:
return E_INVALIDARG;
}
#undef RELATIONTYPE
pvarEndUpAt->vt = VT_EMPTY;
if (xpRelation) {
if (accessible->IsProxy()) {
nsTArray<ProxyAccessible*> targets =
accessible->Proxy()->RelationByType(*xpRelation);
if (targets.Length()) {
navAccessible = WrapperFor(targets[0]);
}
} else {
Relation rel = RelationByType(*xpRelation);
navAccessible = rel.Next();
}
}
if (!navAccessible)
return E_FAIL;
pvarEndUpAt->pdispVal = NativeAccessible(navAccessible);
pvarEndUpAt->vt = VT_DISPATCH;
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::accHitTest(
/* [in] */ long xLeft,
/* [in] */ long yTop,
/* [retval][out] */ VARIANT __RPC_FAR *pvarChild)
{
A11Y_TRYBLOCK_BEGIN
if (!pvarChild)
return E_INVALIDARG;
VariantInit(pvarChild);
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* accessible = nullptr;
if (IsProxy()) {
ProxyAccessible* proxy = Proxy()->ChildAtPoint(xLeft, yTop, eDirectChild);
if (proxy) {
accessible = WrapperFor(proxy);
}
} else {
accessible = ChildAtPoint(xLeft, yTop, eDirectChild);
}
// if we got a child
if (accessible) {
// if the child is us
if (accessible == this) {
pvarChild->vt = VT_I4;
pvarChild->lVal = CHILDID_SELF;
} else { // its not create an Accessible for it.
pvarChild->vt = VT_DISPATCH;
pvarChild->pdispVal = NativeAccessible(accessible);
}
} else {
// no child at that point
pvarChild->vt = VT_EMPTY;
return S_FALSE;
}
return S_OK;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::accDoDefaultAction(
/* [optional][in] */ VARIANT varChild)
{
A11Y_TRYBLOCK_BEGIN
if (IsDefunct())
return CO_E_OBJNOTCONNECTED;
Accessible* xpAccessible = GetXPAccessibleFor(varChild);
if (!xpAccessible)
return E_INVALIDARG;
if (xpAccessible->IsDefunct())
return CO_E_OBJNOTCONNECTED;
// TODO make this work with proxies.
if (xpAccessible->IsProxy())
return xpAccessible->Proxy()->DoAction(0) ? S_OK : E_INVALIDARG;
return xpAccessible->DoAction(0) ? S_OK : E_INVALIDARG;
A11Y_TRYBLOCK_END
}
STDMETHODIMP
AccessibleWrap::put_accName(
/* [optional][in] */ VARIANT varChild,
/* [in] */ BSTR szName)
{
return E_NOTIMPL;
}
STDMETHODIMP
AccessibleWrap::put_accValue(
/* [optional][in] */ VARIANT varChild,
/* [in] */ BSTR szValue)
{
return E_NOTIMPL;
}
////////////////////////////////////////////////////////////////////////////////
// IDispatch
STDMETHODIMP
AccessibleWrap::GetTypeInfoCount(UINT *pctinfo)
{
if (!pctinfo)
return E_INVALIDARG;
*pctinfo = 1;
return S_OK;
}
STDMETHODIMP
AccessibleWrap::GetTypeInfo(UINT iTInfo, LCID lcid, ITypeInfo **ppTInfo)
{
if (!ppTInfo)
return E_INVALIDARG;
*ppTInfo = nullptr;
if (iTInfo != 0)
return DISP_E_BADINDEX;
ITypeInfo * typeInfo = GetTI(lcid);
if (!typeInfo)
return E_FAIL;
typeInfo->AddRef();
*ppTInfo = typeInfo;
return S_OK;
}
STDMETHODIMP
AccessibleWrap::GetIDsOfNames(REFIID riid, LPOLESTR *rgszNames,
UINT cNames, LCID lcid, DISPID *rgDispId)
{
ITypeInfo *typeInfo = GetTI(lcid);
if (!typeInfo)
return E_FAIL;
HRESULT hr = DispGetIDsOfNames(typeInfo, rgszNames, cNames, rgDispId);
return hr;
}
STDMETHODIMP
AccessibleWrap::Invoke(DISPID dispIdMember, REFIID riid,
LCID lcid, WORD wFlags, DISPPARAMS *pDispParams,
VARIANT *pVarResult, EXCEPINFO *pExcepInfo,
UINT *puArgErr)
{
ITypeInfo *typeInfo = GetTI(lcid);
if (!typeInfo)
return E_FAIL;
return typeInfo->Invoke(static_cast<IAccessible*>(this), dispIdMember,
wFlags, pDispParams, pVarResult, pExcepInfo,
puArgErr);
}
void
AccessibleWrap::GetNativeInterface(void** aOutAccessible)
{
*aOutAccessible = static_cast<IAccessible*>(this);
NS_ADDREF_THIS();
}
void
AccessibleWrap::FireWinEvent(Accessible* aTarget, uint32_t aEventType)
{
static_assert(sizeof(gWinEventMap)/sizeof(gWinEventMap[0]) == nsIAccessibleEvent::EVENT_LAST_ENTRY,
"MSAA event map skewed");
NS_ASSERTION(aEventType > 0 && aEventType < ArrayLength(gWinEventMap), "invalid event type");
uint32_t winEvent = gWinEventMap[aEventType];
if (!winEvent)
return;
int32_t childID = GetChildIDFor(aTarget);
if (!childID)
return; // Can't fire an event without a child ID
HWND hwnd = GetHWNDFor(aTarget);
if (!hwnd) {
return;
}
// Fire MSAA event for client area window.
::NotifyWinEvent(winEvent, hwnd, OBJID_CLIENT, childID);
// JAWS announces collapsed combobox navigation based on focus events.
if (aEventType == nsIAccessibleEvent::EVENT_SELECTION &&
Compatibility::IsJAWS()) {
roles::Role role = aTarget->IsProxy() ? aTarget->Proxy()->Role() :
aTarget->Role();
if (role == roles::COMBOBOX_OPTION) {
::NotifyWinEvent(EVENT_OBJECT_FOCUS, hwnd, OBJID_CLIENT, childID);
}
}
}
////////////////////////////////////////////////////////////////////////////////
// Accessible
nsresult
AccessibleWrap::HandleAccEvent(AccEvent* aEvent)
{
nsresult rv = Accessible::HandleAccEvent(aEvent);
NS_ENSURE_SUCCESS(rv, rv);
if (IPCAccessibilityActive()) {
return NS_OK;
}
uint32_t eventType = aEvent->GetEventType();
// Means we're not active.
NS_ENSURE_TRUE(!IsDefunct(), NS_ERROR_FAILURE);
Accessible* accessible = aEvent->GetAccessible();
if (!accessible)
return NS_OK;
if (eventType == nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED ||
eventType == nsIAccessibleEvent::EVENT_FOCUS) {
UpdateSystemCaretFor(accessible);
}
FireWinEvent(accessible, eventType);
return NS_OK;
}
DocProxyAccessibleWrap*
AccessibleWrap::DocProxyWrapper() const
{
MOZ_ASSERT(IsProxy());
ProxyAccessible* proxy = Proxy();
if (!proxy) {
return nullptr;
}
AccessibleWrap* acc = WrapperFor(proxy->Document());
MOZ_ASSERT(acc->IsDoc());
return static_cast<DocProxyAccessibleWrap*>(acc);
}
////////////////////////////////////////////////////////////////////////////////
// AccessibleWrap
//------- Helper methods ---------
int32_t
AccessibleWrap::GetChildIDFor(Accessible* aAccessible)
{
// A child ID of the window is required, when we use NotifyWinEvent,
// so that the 3rd party application can call back and get the IAccessible
// the event occurred on.
if (!aAccessible) {
return 0;
}
#ifdef _WIN64
if (!aAccessible->Document() && !aAccessible->IsProxy())
return 0;
uint32_t* id = & static_cast<AccessibleWrap*>(aAccessible)->mID;
if (*id != kNoID)
return *id;
*id = sIDGen.GetID();
if (aAccessible->IsProxy()) {
DocProxyAccessibleWrap* doc =
static_cast<AccessibleWrap*>(aAccessible)->DocProxyWrapper();
doc->AddID(*id, static_cast<AccessibleWrap*>(aAccessible));
} else {
DocAccessibleWrap* doc =
static_cast<DocAccessibleWrap*>(aAccessible->Document());
doc->AddID(*id, static_cast<AccessibleWrap*>(aAccessible));
}
return *id;
#else
int32_t id = - reinterpret_cast<intptr_t>(aAccessible);
if (aAccessible->IsProxy()) {
DocProxyAccessibleWrap* doc =
static_cast<AccessibleWrap*>(aAccessible)->DocProxyWrapper();
doc->AddID(id, static_cast<AccessibleWrap*>(aAccessible));
}
return id;
#endif
}
HWND
AccessibleWrap::GetHWNDFor(Accessible* aAccessible)
{
if (!aAccessible) {
return nullptr;
}
// Accessibles in child processes are said to have the HWND of the window
// their tab is within. Popups are always in the parent process, and so
// never proxied, which means this is basically correct.
if (aAccessible->IsProxy()) {
ProxyAccessible* proxy = aAccessible->Proxy();
if (!proxy) {
return nullptr;
}
Accessible* outerDoc = proxy->OuterDocOfRemoteBrowser();
NS_ASSERTION(outerDoc, "no outer doc for accessible remote tab!");
if (!outerDoc) {
return nullptr;
}
return GetHWNDFor(outerDoc);
}
DocAccessible* document = aAccessible->Document();
if(!document)
return nullptr;
// Popup lives in own windows, use its HWND until the popup window is
// hidden to make old JAWS versions work with collapsed comboboxes (see
// discussion in bug 379678).
nsIFrame* frame = aAccessible->GetFrame();
if (frame) {
nsIWidget* widget = frame->GetNearestWidget();
if (widget && widget->IsVisible()) {
nsIPresShell* shell = document->PresShell();
nsViewManager* vm = shell->GetViewManager();
if (vm) {
nsCOMPtr<nsIWidget> rootWidget;
vm->GetRootWidget(getter_AddRefs(rootWidget));
// Make sure the accessible belongs to popup. If not then use
// document HWND (which might be different from root widget in the
// case of window emulation).
if (rootWidget != widget)
return static_cast<HWND>(widget->GetNativeData(NS_NATIVE_WINDOW));
}
}
}
return static_cast<HWND>(document->GetNativeWindow());
}
IDispatch*
AccessibleWrap::NativeAccessible(Accessible* aAccessible)
{
if (!aAccessible) {
NS_WARNING("Not passing in an aAccessible");
return nullptr;
}
IAccessible* msaaAccessible = nullptr;
aAccessible->GetNativeInterface(reinterpret_cast<void**>(&msaaAccessible));
return static_cast<IDispatch*>(msaaAccessible);
}
#ifdef _WIN64
static Accessible*
GetAccessibleInSubtree(DocAccessible* aDoc, uint32_t aID)
{
Accessible* child = static_cast<DocAccessibleWrap*>(aDoc)->GetAccessibleByID(aID);
if (child)
return child;
uint32_t childDocCount = aDoc->ChildDocumentCount();
for (uint32_t i = 0; i < childDocCount; i++) {
child = GetAccessibleInSubtree(aDoc->GetChildDocumentAt(i), aID);
if (child)
return child;
}
return nullptr;
}
#endif
static AccessibleWrap*
GetProxiedAccessibleInSubtree(const DocAccessibleParent* aDoc, uint32_t aID)
{
auto wrapper = static_cast<DocProxyAccessibleWrap*>(WrapperFor(aDoc));
AccessibleWrap* child = wrapper->GetAccessibleByID(aID);
if (child) {
return child;
}
size_t childDocs = aDoc->ChildDocCount();
for (size_t i = 0; i < childDocs; i++) {
const DocAccessibleParent* childDoc = aDoc->ChildDocAt(i);
child = GetProxiedAccessibleInSubtree(childDoc, aID);
if (child) {
return child;
}
}
return nullptr;
}
Accessible*
AccessibleWrap::GetXPAccessibleFor(const VARIANT& aVarChild)
{
if (aVarChild.vt != VT_I4)
return nullptr;
// if its us real easy - this seems to always be the case
if (aVarChild.lVal == CHILDID_SELF)
return this;
if (IsProxy() ? Proxy()->MustPruneChildren() : nsAccUtils::MustPrune(this)) {
return nullptr;
}
if (aVarChild.lVal > 0) {
// Gecko child indices are 0-based in contrast to indices used in MSAA.
if (IsProxy()) {
return WrapperFor(Proxy()->ChildAt(aVarChild.lVal - 1));
} else {
return GetChildAt(aVarChild.lVal - 1);
}
}
// If lVal negative then it is treated as child ID and we should look for
// accessible through whole accessible subtree including subdocuments.
// Otherwise we treat lVal as index in parent.
// Convert child ID to unique ID.
// First handle the case that both this accessible and the id'd one are in
// this process.
if (!IsProxy()) {
void* uniqueID = reinterpret_cast<void*>(-aVarChild.lVal);
DocAccessible* document = Document();
Accessible* child =
#ifdef _WIN64
GetAccessibleInSubtree(document, static_cast<uint32_t>(aVarChild.lVal));
#else
document->GetAccessibleByUniqueIDInSubtree(uniqueID);
#endif
// If it is a document then just return an accessible.
if (child && IsDoc())
return child;
// Otherwise check whether the accessible is a child (this path works for
// ARIA documents and popups).
Accessible* parent = child;
while (parent && parent != document) {
if (parent == this)
return child;
parent = parent->Parent();
}
}
// Now see about the case that both this accessible and the target one are
// proxied.
uint32_t id = aVarChild.lVal;
if (IsProxy()) {
DocAccessibleParent* proxyDoc = Proxy()->Document();
AccessibleWrap* wrapper = GetProxiedAccessibleInSubtree(proxyDoc, id);
if (!wrapper)
return nullptr;
MOZ_ASSERT(wrapper->IsProxy());
if (proxyDoc == this->Proxy()) {
return wrapper;
}
ProxyAccessible* parent = wrapper->Proxy();
while (parent && parent != proxyDoc) {
if (parent == this->Proxy()) {
return wrapper;
}
parent = parent->Parent();
}
return nullptr;
}
// Finally we need to handle the case that this accessible is in the main
// process, but the target is proxied. This is the case when the target
// accessible is in a child document of this one.
DocAccessibleParent* proxyDoc = nullptr;
DocAccessible* doc = Document();
const nsTArray<DocAccessibleParent*>* remoteDocs =
DocManager::TopLevelRemoteDocs();
if (!remoteDocs) {
return nullptr;
}
size_t docCount = remoteDocs->Length();
for (size_t i = 0; i < docCount; i++) {
Accessible* outerDoc = remoteDocs->ElementAt(i)->OuterDocOfRemoteBrowser();
if (!outerDoc) {
continue;
}
if (outerDoc->Document() != doc) {
continue;
}
if (doc == this) {
AccessibleWrap* proxyWrapper =
GetProxiedAccessibleInSubtree(remoteDocs->ElementAt(i), id);
if (proxyWrapper) {
return proxyWrapper;
}
continue;
}
Accessible* parent = outerDoc;
while (parent && parent != doc) {
if (parent == this) {
AccessibleWrap* proxyWrapper =
GetProxiedAccessibleInSubtree(remoteDocs->ElementAt(i), id);
if (proxyWrapper) {
return proxyWrapper;
}
}
parent = parent->Parent();
}
}
return nullptr;
}
void
AccessibleWrap::UpdateSystemCaretFor(Accessible* aAccessible)
{
// Move the system caret so that Windows Tablet Edition and tradional ATs with
// off-screen model can follow the caret
::DestroyCaret();
HyperTextAccessible* text = aAccessible->AsHyperText();
if (!text)
return;
nsIWidget* widget = nullptr;
LayoutDeviceIntRect caretRect = text->GetCaretRect(&widget);
HWND caretWnd;
if (caretRect.IsEmpty() || !(caretWnd = (HWND)widget->GetNativeData(NS_NATIVE_WINDOW))) {
return;
}
// Create invisible bitmap for caret, otherwise its appearance interferes
// with Gecko caret
HBITMAP caretBitMap = CreateBitmap(1, caretRect.height, 1, 1, nullptr);
if (::CreateCaret(caretWnd, caretBitMap, 1, caretRect.height)) { // Also destroys the last caret
::ShowCaret(caretWnd);
RECT windowRect;
::GetWindowRect(caretWnd, &windowRect);
::SetCaretPos(caretRect.x - windowRect.left, caretRect.y - windowRect.top);
::DeleteObject(caretBitMap);
}
}
ITypeInfo*
AccessibleWrap::GetTI(LCID lcid)
{
if (gTypeInfo)
return gTypeInfo;
ITypeLib *typeLib = nullptr;
HRESULT hr = LoadRegTypeLib(LIBID_Accessibility, 1, 0, lcid, &typeLib);
if (FAILED(hr))
return nullptr;
hr = typeLib->GetTypeInfoOfGuid(IID_IAccessible, &gTypeInfo);
typeLib->Release();
if (FAILED(hr))
return nullptr;
return gTypeInfo;
}