qaccessible.cpp

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#include "qaccessible.h"

#ifndef QT_NO_ACCESSIBILITY

#include "qaccessibleplugin.h"
#include "qaccessiblewidget.h"
#include "qapplication.h"
#include "qhash.h"
#include "qmetaobject.h"
#include "qmutex.h"
#include <private/qfactoryloader_p.h>

#include "qwidget.h"

QT_BEGIN_NAMESPACE

#ifndef QT_NO_LIBRARY
Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
    (QAccessibleFactoryInterface_iid, QLatin1String("/accessible")))
#endif

Q_GLOBAL_STATIC(QList<QAccessible::InterfaceFactory>, qAccessibleFactories)

QAccessible::UpdateHandler QAccessible::updateHandler = 0;
QAccessible::RootObjectHandler QAccessible::rootObjectHandler = 0;

static bool accessibility_active = false;
static bool cleanupAdded = false;
static void qAccessibleCleanup()
{
    qAccessibleFactories()->clear();
}

void QAccessible::installFactory(InterfaceFactory factory)
{
    if (!factory)
        return;

    if (!cleanupAdded) {
        qAddPostRoutine(qAccessibleCleanup);
        cleanupAdded = true;
    }
    if (qAccessibleFactories()->contains(factory))
        return;
    qAccessibleFactories()->append(factory);
}

void QAccessible::removeFactory(InterfaceFactory factory)
{
    qAccessibleFactories()->removeAll(factory);
}

QAccessible::UpdateHandler QAccessible::installUpdateHandler(UpdateHandler handler)
{
    UpdateHandler old = updateHandler;
    updateHandler = handler;
    return old;
}

QAccessible::RootObjectHandler QAccessible::installRootObjectHandler(RootObjectHandler handler)
{
    RootObjectHandler old = rootObjectHandler;
    rootObjectHandler = handler;
    return old;
}

QAccessibleInterface *QAccessible::queryAccessibleInterface(QObject *object)
{
    accessibility_active = true;
    QAccessibleInterface *iface = 0;
    if (!object)
        return 0;

    const QMetaObject *mo = object->metaObject();
    while (mo) {
        const QLatin1String cn(mo->className());
        for (int i = qAccessibleFactories()->count(); i > 0; --i) {
            InterfaceFactory factory = qAccessibleFactories()->at(i - 1);
            iface = factory(cn, object);
            if (iface)
                return iface;
        }
#ifndef QT_NO_LIBRARY
        QAccessibleFactoryInterface *factory = qobject_cast<QAccessibleFactoryInterface*>(loader()->instance(cn));
        if (factory) {
            iface = factory->create(cn, object);
            if (iface)
                return iface;
        }
#endif
        mo = mo->superClass();
    }

    QWidget *widget = qobject_cast<QWidget*>(object);
    if (widget)
        return new QAccessibleWidget(widget);
    else if (object == qApp)
        return new QAccessibleApplication();

    return 0;
}

bool QAccessible::isActive()
{
    return accessibility_active;
}

QVariant QAccessibleInterface::invokeMethod(Method method, int child, const QVariantList &params)
{
    if (!(state(0) & HasInvokeExtension))
        return QVariant();

    return static_cast<QAccessibleInterfaceEx *>(this)->invokeMethodEx(method, child, params);
}

QVariant QAccessibleInterfaceEx::virtual_hook(const QVariant &)
{
    return QVariant();
}

QAccessible2Interface *QAccessibleInterface::cast_helper(QAccessible2::InterfaceType t)
{
    if (state(0) & HasInvokeExtension)
        return static_cast<QAccessibleInterfaceEx *>(this)->interface_cast(t);
    return 0;
}

QT_END_NAMESPACE

#endif