qaccessibleobject.cpp

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#include "qaccessibleobject.h"

#ifndef QT_NO_ACCESSIBILITY

#include "qapplication.h"
#include "qwidget.h"
#include "qpointer.h"
#include "qmetaobject.h"
#include "qvarlengtharray.h"

QT_BEGIN_NAMESPACE

class QAccessibleObjectPrivate
{
public:
    QPointer<QObject> object;

    QList<QByteArray> actionList() const;
};

QList<QByteArray> QAccessibleObjectPrivate::actionList() const
{
    QList<QByteArray> actionList;

    if (!object)
        return actionList;

    const QMetaObject *mo = object->metaObject();
    Q_ASSERT(mo);

    QByteArray defaultAction = QMetaObject::normalizedSignature(
        mo->classInfo(mo->indexOfClassInfo("DefaultSlot")).value());

    for (int i = 0; i < mo->methodCount(); ++i) {
        const QMetaMethod member = mo->method(i);
        if (member.methodType() != QMetaMethod::Slot && member.access() != QMetaMethod::Public)
            continue;

        if (!qstrcmp(member.tag(), "QACCESSIBLE_SLOT")) {
            if (member.signature() == defaultAction)
                actionList.prepend(defaultAction);
            else
                actionList << member.signature();
        }
    }

    return actionList;
}

QAccessibleObject::QAccessibleObject(QObject *object)
{
    d = new QAccessibleObjectPrivate;
    d->object = object;
}

QAccessibleObject::~QAccessibleObject()
{
    delete d;
}

QObject *QAccessibleObject::object() const
{
#ifndef QT_NO_DEBUG
    if (!d->object)
        qWarning("QAccessibleInterface is invalid. Crash pending...");
#endif
    return d->object;
}

bool QAccessibleObject::isValid() const
{
    return !d->object.isNull();
}

QRect QAccessibleObject::rect(int) const
{
    return QRect();
}

void QAccessibleObject::setText(Text, int, const QString &)
{
}

int QAccessibleObject::userActionCount(int) const
{
    return 0;
}

bool QAccessibleObject::doAction(int, int, const QVariantList &)
{
    return false;
}

static const char * const action_text[][5] =
{
    // Name, Description, Value, Help, Accelerator
    { "Press", "", "", "", "Space" },
    { "SetFocus", "Passes focus to this widget", "", "", "" },
    { "Increase", "", "", "", "" },
    { "Decrease", "", "", "", "" },
    { "Accept", "", "", "", "" },
    { "Cancel", "", "", "", "" },
    { "Select", "", "", "", "" },
    { "ClearSelection", "", "", "", "" },
    { "RemoveSelection", "", "", "", "" },
    { "ExtendSelection", "", "", "", "" },
    { "AddToSelection", "", "", "", "" }
};

QString QAccessibleObject::actionText(int action, Text t, int child) const
{
    if (child || action > FirstStandardAction || action < LastStandardAction || t > Accelerator)
        return QString();

    return QString::fromLatin1(action_text[-(action - FirstStandardAction)][t]);
}


QAccessibleApplication::QAccessibleApplication()
: QAccessibleObject(qApp)
{
}

// all toplevel widgets except popups and the desktop
static QWidgetList topLevelWidgets()
{
    QWidgetList list;
    const QWidgetList tlw(QApplication::topLevelWidgets());
    for (int i = 0; i < tlw.count(); ++i) {
        QWidget *w = tlw.at(i);
        if (!(w->windowType() == Qt::Popup) && !(w->windowType() == Qt::Desktop))
            list.append(w);
    }

    return list;
}

int QAccessibleApplication::childCount() const
{
    return topLevelWidgets().count();
}

int QAccessibleApplication::indexOfChild(const QAccessibleInterface *child) const
{
    if (!child->object()->isWidgetType())
        return -1;

    const QWidgetList tlw(topLevelWidgets());
    int index = tlw.indexOf(static_cast<QWidget*>(child->object()));
    if (index != -1)
        ++index;
    return index;
}

int QAccessibleApplication::childAt(int x, int y) const
{
    const QWidgetList tlw(topLevelWidgets());
    for (int i = 0; i < tlw.count(); ++i) {
        QWidget *w = tlw.at(i);
        if (w->frameGeometry().contains(x,y))
            return i+1;
    }
    return -1;
}

QAccessible::Relation QAccessibleApplication::relationTo(int child, const
        QAccessibleInterface *other, int otherChild) const
{
    QObject *o = other ? other->object() : 0;
    if (!o)
        return Unrelated;

    if(o == object()) {
        if (child && !otherChild)
            return Child;
        if (!child && otherChild)
            return Ancestor;
        if (!child && !otherChild)
            return Self;
    }

    QWidgetList tlw(topLevelWidgets());
    if (tlw.contains(qobject_cast<QWidget*>(o)))
        return Ancestor;

    for (int i = 0; i < tlw.count(); ++i) {
        QWidget *w = tlw.at(i);
        QObjectList cl = w->findChildren<QObject *>(QString());
        if (cl.contains(o))
            return Ancestor;
    }

    return Unrelated;
}

int QAccessibleApplication::navigate(RelationFlag relation, int entry,
                                     QAccessibleInterface **target) const
{
    if (!target)
        return -1;

    *target = 0;
    QObject *targetObject = 0;

    switch (relation) {
    case Self:
        targetObject = object();
        break;
    case Child:
        if (entry > 0 && entry <= childCount()) {
            const QWidgetList tlw(topLevelWidgets());
            if (tlw.count() >= entry)
                targetObject = tlw.at(entry-1);
        } else {
            return -1;
        }
        break;
    case FocusChild:
        targetObject = QApplication::activeWindow();
        break;
    default:
        break;
    }
    *target = QAccessible::queryAccessibleInterface(targetObject);
    return *target ? 0 : -1;
}

QString QAccessibleApplication::text(Text t, int) const
{
    switch (t) {
    case Name:
        return QApplication::applicationName();
    case Description:
        return QApplication::applicationFilePath();
    default:
        break;
    }
    return QString();
}

QAccessible::Role QAccessibleApplication::role(int) const
{
    return Application;
}

QAccessible::State QAccessibleApplication::state(int) const
{
    return QApplication::activeWindow() ? Focused : Normal;
}

int QAccessibleApplication::userActionCount(int) const
{
    return 1;
}

bool QAccessibleApplication::doAction(int action, int child, const QVariantList &param)
{
    if (action == 0 || action == 1) {
        QWidget *w = 0;
        w = QApplication::activeWindow();
        if (!w)
            w = topLevelWidgets().at(0);
        if (!w)
            return false;
        w->activateWindow();
        return true;
    }
    return QAccessibleObject::doAction(action, child, param);
}

QString QAccessibleApplication::actionText(int action, Text text, int child) const
{
    QString str;
    if ((action == 0 || action == 1) && !child) switch (text) {
    case Name:
        return QApplication::tr("Activate");
    case Description:
        return QApplication::tr("Activates the program's main window");
    default:
        break;
    }
    return QAccessibleObject::actionText(action, text, child);
}

// ### Qt 5: remove me - binary compatibility hack
QAccessibleObjectEx::QAccessibleObjectEx(QObject *object)
{
    d = new QAccessibleObjectPrivate;
    d->object = object;
}
bool QAccessibleObjectEx::isValid() const
{ return reinterpret_cast<const QAccessibleObject *>(this)->QAccessibleObject::isValid(); }
QObject *QAccessibleObjectEx::object() const
{ return reinterpret_cast<const QAccessibleObject *>(this)->QAccessibleObject::object(); }
QRect QAccessibleObjectEx::rect(int child) const
{ return reinterpret_cast<const QAccessibleObject *>(this)->QAccessibleObject::rect(child); }
void QAccessibleObjectEx::setText(Text t, int child, const QString &text)
{ reinterpret_cast<QAccessibleObject *>(this)->QAccessibleObject::setText(t, child, text); }
int QAccessibleObjectEx::userActionCount(int child) const
{ return reinterpret_cast<const QAccessibleObject *>(this)->QAccessibleObject::userActionCount(child); }
bool QAccessibleObjectEx::doAction(int action, int child, const QVariantList &params)
{ return reinterpret_cast<QAccessibleObject *>(this)->QAccessibleObject::doAction(action, child, params); }
QString QAccessibleObjectEx::actionText(int action, Text t, int child) const
{ return reinterpret_cast<const QAccessibleObject *>(this)->QAccessibleObject::actionText(action, t, child); }
QAccessibleObjectEx::~QAccessibleObjectEx()
{ delete d; }

QT_END_NAMESPACE

#endif //QT_NO_ACCESSIBILITY