AccessibleContextBase.cxx

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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#include <editeng/AccessibleContextBase.hxx>
 
#include <com/sun/star/accessibility/XAccessibleEventListener.hpp>
#include <com/sun/star/accessibility/AccessibleStateType.hpp>
#include <com/sun/star/accessibility/AccessibleRelationType.hpp>
#include <com/sun/star/lang/IndexOutOfBoundsException.hpp>
#include <com/sun/star/accessibility/AccessibleEventId.hpp>
#include <com/sun/star/accessibility/IllegalAccessibleComponentStateException.hpp>
 
#include <unotools/accessiblerelationsethelper.hxx>
#include <comphelper/accessibleeventnotifier.hxx>
#include <cppuhelper/supportsservice.hxx>
#include <osl/mutex.hxx>
#include <rtl/ref.hxx>
 
#include <utility>
 
using namespace ::com::sun::star;
using namespace ::com::sun::star::accessibility;
 
namespace accessibility {
 
// internal
 
AccessibleContextBase::AccessibleContextBase (
        uno::Reference<XAccessible> xParent,
        const sal_Int16 aRole)
    :   WeakComponentImplHelper(m_aMutex),
        mxParent(std::move(xParent)),
        meDescriptionOrigin(NotSet),
        meNameOrigin(NotSet),
        mnClientId(0),
        maRole(aRole)
{
    // Create the state set.
    mnStateSet = 0;
 
    // Set some states.  Don't use the SetState method because no events
    // shall be broadcasted (that is not yet initialized anyway).
    mnStateSet |= AccessibleStateType::ENABLED;
    mnStateSet |= AccessibleStateType::SENSITIVE;
    mnStateSet |= AccessibleStateType::SHOWING;
    mnStateSet |= AccessibleStateType::VISIBLE;
    mnStateSet |= AccessibleStateType::FOCUSABLE;
    mnStateSet |= AccessibleStateType::SELECTABLE;
 
    // Create the relation set.
    mxRelationSet = new ::utl::AccessibleRelationSetHelper ();
}
 
AccessibleContextBase::~AccessibleContextBase()
{
}
 
bool AccessibleContextBase::SetState (sal_Int64 aState)
{
    ::osl::ClearableMutexGuard aGuard (m_aMutex);
    if (!(mnStateSet & aState))
    {
        mnStateSet |= aState;
        // Clear the mutex guard so that it is not locked during calls to
        // listeners.
        aGuard.clear();
 
        // Send event for all states except the DEFUNC state.
        if (aState != AccessibleStateType::DEFUNC)
        {
            uno::Any aNewValue;
            aNewValue <<= aState;
            CommitChange(
                AccessibleEventId::STATE_CHANGED,
                aNewValue,
                uno::Any(), -1);
        }
        return true;
    }
    else
        return false;
}
 
 
bool AccessibleContextBase::ResetState (sal_Int64 aState)
{
    ::osl::ClearableMutexGuard aGuard (m_aMutex);
    if (mnStateSet & aState)
    {
        mnStateSet &= ~aState;
        // Clear the mutex guard so that it is not locked during calls to listeners.
        aGuard.clear();
 
        uno::Any aOldValue;
        aOldValue <<= aState;
        CommitChange(
            AccessibleEventId::STATE_CHANGED,
            uno::Any(),
            aOldValue, -1);
        return true;
    }
    else
        return false;
}
 
 
bool AccessibleContextBase::GetState (sal_Int64 aState)
{
    ::osl::MutexGuard aGuard (m_aMutex);
    return mnStateSet & aState;
}
 
 
void AccessibleContextBase::SetRelationSet (
    const uno::Reference<XAccessibleRelationSet>& rxNewRelationSet)
{
    // Try to emit some meaningful events indicating differing relations in
    // both sets.
    typedef std::pair<short int,short int> RD;
    const RD aRelationDescriptors[] = {
        RD(AccessibleRelationType::CONTROLLED_BY, AccessibleEventId::CONTROLLED_BY_RELATION_CHANGED),
        RD(AccessibleRelationType::CONTROLLER_FOR, AccessibleEventId::CONTROLLER_FOR_RELATION_CHANGED),
        RD(AccessibleRelationType::LABELED_BY, AccessibleEventId::LABELED_BY_RELATION_CHANGED),
        RD(AccessibleRelationType::LABEL_FOR, AccessibleEventId::LABEL_FOR_RELATION_CHANGED),
        RD(AccessibleRelationType::MEMBER_OF, AccessibleEventId::MEMBER_OF_RELATION_CHANGED),
        RD(AccessibleRelationType::INVALID, -1),
    };
    for (int i=0; aRelationDescriptors[i].first!=AccessibleRelationType::INVALID; i++)
        if (mxRelationSet->containsRelation(aRelationDescriptors[i].first)
        != rxNewRelationSet->containsRelation(aRelationDescriptors[i].first))
        CommitChange (aRelationDescriptors[i].second, uno::Any(), uno::Any(), -1);
 
    mxRelationSet = rxNewRelationSet;
}
 
 
// XAccessible
 
uno::Reference< XAccessibleContext> SAL_CALL
    AccessibleContextBase::getAccessibleContext()
{
    return this;
}
 
 
// XAccessibleContext
 
sal_Int64 SAL_CALL
       AccessibleContextBase::getAccessibleChildCount()
{
    return 0;
}
 
 
uno::Reference<XAccessible> SAL_CALL
    AccessibleContextBase::getAccessibleChild (sal_Int64 nIndex)
{
    ThrowIfDisposed ();
    throw lang::IndexOutOfBoundsException (
        "no child with index " + OUString::number(nIndex),
        nullptr);
}
 
 
uno::Reference<XAccessible> SAL_CALL
       AccessibleContextBase::getAccessibleParent()
{
    ThrowIfDisposed ();
    return mxParent;
}
 
 
sal_Int64 SAL_CALL
       AccessibleContextBase::getAccessibleIndexInParent()
{
    ThrowIfDisposed ();
    //  Use a simple but slow solution for now.  Optimize later.
 
    //  Iterate over all the parent's children and search for this object.
    if (!mxParent.is())
        //   Return -1 to indicate that this object's parent does not know about the
        //   object.
        return -1;
 
    uno::Reference<XAccessibleContext> xParentContext (
        mxParent->getAccessibleContext());
    if (xParentContext.is())
    {
        sal_Int64 nChildCount = xParentContext->getAccessibleChildCount();
        for (sal_Int64 i=0; i<nChildCount; i++)
        {
            uno::Reference<XAccessible> xChild (xParentContext->getAccessibleChild (i));
            if (xChild.is())
            {
                uno::Reference<XAccessibleContext> xChildContext = xChild->getAccessibleContext();
                if (xChildContext == static_cast<XAccessibleContext*>(this))
                    return i;
            }
        }
    }
 
    //   Return -1 to indicate that this object's parent does not know about the
    //   object.
    return -1;
}
 
 
sal_Int16 SAL_CALL
    AccessibleContextBase::getAccessibleRole()
{
    ThrowIfDisposed ();
    return maRole;
}
 
 
OUString SAL_CALL
       AccessibleContextBase::getAccessibleDescription()
{
    ThrowIfDisposed ();
 
    return msDescription;
}
 
 
OUString SAL_CALL
       AccessibleContextBase::getAccessibleName()
{
    ThrowIfDisposed ();
 
    if (meNameOrigin == NotSet)
    {
        // Do not send an event because this is the first time it has been
        // requested.
        msName = CreateAccessibleName();
        meNameOrigin = AutomaticallyCreated;
    }
 
    return msName;
}
 
 
uno::Reference<XAccessibleRelationSet> SAL_CALL
       AccessibleContextBase::getAccessibleRelationSet()
{
    ThrowIfDisposed ();
 
    // Create a copy of the relation set and return it.
    ::utl::AccessibleRelationSetHelper* pRelationSet =
        static_cast< ::utl::AccessibleRelationSetHelper*>(mxRelationSet.get());
    if (pRelationSet != nullptr)
    {
        return uno::Reference<XAccessibleRelationSet> (
            new ::utl::AccessibleRelationSetHelper (*pRelationSet));
    }
    else
        return uno::Reference<XAccessibleRelationSet>(nullptr);
}
 
 
sal_Int64 SAL_CALL
    AccessibleContextBase::getAccessibleStateSet()
{
    if (rBHelper.bDisposed)
    {
        // We are already disposed!
        // Create a new state set that has only set the DEFUNC state.
        return AccessibleStateType::DEFUNC;
    }
    else
    {
        return mnStateSet;
    }
}
 
 
lang::Locale SAL_CALL
       AccessibleContextBase::getLocale()
{
    ThrowIfDisposed ();
    // Delegate request to parent.
    if (mxParent.is())
    {
        uno::Reference<XAccessibleContext> xParentContext (
            mxParent->getAccessibleContext());
        if (xParentContext.is())
            return xParentContext->getLocale ();
    }
 
    //  No locale and no parent.  Therefore throw exception to indicate this
    //  cluelessness.
    throw IllegalAccessibleComponentStateException ();
}
 
 
// XAccessibleEventListener
 
void SAL_CALL AccessibleContextBase::addAccessibleEventListener (
        const uno::Reference<XAccessibleEventListener >& rxListener)
{
    if (!rxListener.is())
        return;
 
    if (rBHelper.bDisposed || rBHelper.bInDispose)
    {
        uno::Reference<uno::XInterface> x (static_cast<lang::XComponent *>(this), uno::UNO_QUERY);
        rxListener->disposing (lang::EventObject (x));
    }
    else
    {
        if (!mnClientId)
            mnClientId = comphelper::AccessibleEventNotifier::registerClient( );
        comphelper::AccessibleEventNotifier::addEventListener( mnClientId, rxListener );
    }
}
 
 
void SAL_CALL AccessibleContextBase::removeAccessibleEventListener (
        const uno::Reference<XAccessibleEventListener >& rxListener )
{
    ThrowIfDisposed ();
    if (!(rxListener.is() && mnClientId))
        return;
 
    sal_Int32 nListenerCount = comphelper::AccessibleEventNotifier::removeEventListener( mnClientId, rxListener );
    if ( !nListenerCount )
    {
        // no listeners anymore
        // -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
        // and at least to us not firing any events anymore, in case somebody calls
        // NotifyAccessibleEvent, again
        comphelper::AccessibleEventNotifier::revokeClient( mnClientId );
        mnClientId = 0;
    }
}
 
// XServiceInfo
OUString SAL_CALL AccessibleContextBase::getImplementationName()
{
    return "AccessibleContextBase";
}
 
sal_Bool SAL_CALL AccessibleContextBase::supportsService (const OUString& sServiceName)
{
    return cppu::supportsService(this, sServiceName);
}
 
uno::Sequence< OUString > SAL_CALL
       AccessibleContextBase::getSupportedServiceNames()
{
    return {
        "com.sun.star.accessibility.Accessible",
        "com.sun.star.accessibility.AccessibleContext"};
}
 
 
// XTypeProvider
 
uno::Sequence<sal_Int8> SAL_CALL
    AccessibleContextBase::getImplementationId()
{
    return css::uno::Sequence<sal_Int8>();
}
 
// internal
 
void SAL_CALL AccessibleContextBase::disposing()
{
    SetState (AccessibleStateType::DEFUNC);
 
    ::osl::MutexGuard aGuard (m_aMutex);
 
    // Send a disposing to all listeners.
    if ( mnClientId )
    {
        comphelper::AccessibleEventNotifier::revokeClientNotifyDisposing( mnClientId, *this );
        mnClientId =  0;
    }
    mxParent.clear();
    mxRelationSet.clear();
}
 
 
void AccessibleContextBase::SetAccessibleDescription (
    const OUString& rDescription,
    StringOrigin eDescriptionOrigin)
{
    if (!(eDescriptionOrigin < meDescriptionOrigin
        || (eDescriptionOrigin == meDescriptionOrigin && msDescription != rDescription)))
        return;
 
    uno::Any aOldValue, aNewValue;
    aOldValue <<= msDescription;
    aNewValue <<= rDescription;
 
    msDescription = rDescription;
    meDescriptionOrigin = eDescriptionOrigin;
 
    CommitChange(
        AccessibleEventId::DESCRIPTION_CHANGED,
        aNewValue,
        aOldValue, -1);
}
 
 
void AccessibleContextBase::SetAccessibleName (
    const OUString& rName,
    StringOrigin eNameOrigin)
{
    if (!(eNameOrigin < meNameOrigin
        || (eNameOrigin == meNameOrigin && msName != rName)))
        return;
 
    uno::Any aOldValue, aNewValue;
    aOldValue <<= msName;
    aNewValue <<= rName;
 
    msName = rName;
    meNameOrigin = eNameOrigin;
 
    CommitChange(
        AccessibleEventId::NAME_CHANGED,
        aNewValue,
        aOldValue, -1);
}
 
 
OUString AccessibleContextBase::CreateAccessibleName()
{
    return "Empty Name";
}
 
 
void AccessibleContextBase::CommitChange (
    sal_Int16 nEventId,
    const uno::Any& rNewValue,
    const uno::Any& rOldValue,
    sal_Int32 nValueIndex)
{
    // Do not call FireEvent and do not even create the event object when no
    // listener has been registered yet.  Creating the event object can
    // otherwise lead to a crash.  See issue 93419 for details.
    if (mnClientId != 0)
    {
        AccessibleEventObject aEvent (
            static_cast<XAccessibleContext*>(this),
            nEventId,
            rNewValue,
            rOldValue,
            nValueIndex);
 
        FireEvent (aEvent);
    }
}
 
 
void AccessibleContextBase::FireEvent (const AccessibleEventObject& aEvent)
{
    if (mnClientId)
        comphelper::AccessibleEventNotifier::addEvent( mnClientId, aEvent );
}
 
 
void AccessibleContextBase::ThrowIfDisposed()
{
    if (rBHelper.bDisposed || rBHelper.bInDispose)
    {
        throw lang::DisposedException ("object has been already disposed",
            getXWeak());
    }
}
 
 
bool AccessibleContextBase::IsDisposed() const
{
    return (rBHelper.bDisposed || rBHelper.bInDispose);
}
 
 
void AccessibleContextBase::SetAccessibleRole( sal_Int16 _nRole )
{
    maRole = _nRole;
}
 
 
} // end of namespace accessibility
 
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