Improve restoring of miximized window geomertry.

[qt:qt.git] / src / gui / kernel / qwidget.cpp

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#include "qapplication.h"
#include "qapplication_p.h"
#include "qbrush.h"
#include "qcursor.h"
#include "qdesktopwidget.h"
#include "qevent.h"
#include "qhash.h"
#include "qlayout.h"
#include "qmenu.h"
#include "qmetaobject.h"
#include "qpixmap.h"
#include "qpointer.h"
#include "qstack.h"
#include "qstyle.h"
#include "qstylefactory.h"
#include "qvariant.h"
#include "qwidget.h"
#include "qstyleoption.h"
#ifndef QT_NO_ACCESSIBILITY
# include "qaccessible.h"
#endif
#if defined(Q_WS_WIN)
# include "qt_windows.h"
#endif
#ifdef Q_WS_MAC
# include "qt_mac_p.h"
# include "qt_cocoa_helpers_mac_p.h"
# include "qmainwindow.h"
# include "qtoolbar.h"
# include <private/qmainwindowlayout_p.h>
#endif
#if defined(Q_WS_QWS)
# include "qwsdisplay_qws.h"
# include "qwsmanager_qws.h"
# include "qpaintengine.h" // for PorterDuff
# include "private/qwindowsurface_qws_p.h"
#endif
#if defined(Q_WS_QPA)
#include "qplatformwindow_qpa.h"
#endif
#include "qpainter.h"
#include "qtooltip.h"
#include "qwhatsthis.h"
#include "qdebug.h"
#include "private/qstylesheetstyle_p.h"
#include "private/qstyle_p.h"
#include "private/qinputcontext_p.h"
#include "qfileinfo.h"
#include "private/qsoftkeymanager_p.h"

#if defined (Q_WS_WIN)
# include <private/qwininputcontext_p.h>
#endif

#if defined(Q_WS_X11)
# include <private/qpaintengine_x11_p.h>
# include "qx11info_x11.h"
#endif

#include <private/qgraphicseffect_p.h>
#include <private/qwindowsurface_p.h>
#include <private/qbackingstore_p.h>
#ifdef Q_WS_MAC
# include <private/qpaintengine_mac_p.h>
#endif
#include <private/qpaintengine_raster_p.h>

#if defined(Q_OS_SYMBIAN)
#include "private/qt_s60_p.h"
#endif

#include "qwidget_p.h"
#include "qaction_p.h"
#include "qlayout_p.h"
#include "QtGui/qgraphicsproxywidget.h"
#include "QtGui/qgraphicsscene.h"
#include "private/qgraphicsproxywidget_p.h"
#include "QtGui/qabstractscrollarea.h"
#include "private/qabstractscrollarea_p.h"
#include "private/qevent_p.h"

#include "private/qgraphicssystem_p.h"
#include "private/qgesturemanager_p.h"

#ifdef QT_KEYPAD_NAVIGATION
#include "qtabwidget.h" // Needed in inTabWidget()
#endif // QT_KEYPAD_NAVIGATION

// widget/widget data creation count
//#define QWIDGET_EXTRA_DEBUG
//#define ALIEN_DEBUG

QT_BEGIN_NAMESPACE

#if !defined(Q_WS_QWS)
static bool qt_enable_backingstore = true;
#endif
#ifdef Q_WS_X11
// for compatibility with Qt 4.0
Q_GUI_EXPORT void qt_x11_set_global_double_buffer(bool enable)
{
    qt_enable_backingstore = enable;
}
#endif

static inline bool qRectIntersects(const QRect &r1, const QRect &r2)
{
    return (qMax(r1.left(), r2.left()) <= qMin(r1.right(), r2.right()) &&
            qMax(r1.top(), r2.top()) <= qMin(r1.bottom(), r2.bottom()));
}

static inline bool hasBackingStoreSupport()
{
#ifdef Q_WS_MAC
    return QApplicationPrivate::graphicsSystem() != 0;
#else
    return true;
#endif
}

#ifdef Q_WS_MAC
#  define QT_NO_PAINT_DEBUG
#endif

extern bool qt_sendSpontaneousEvent(QObject*, QEvent*); // qapplication.cpp
extern QDesktopWidget *qt_desktopWidget; // qapplication.cpp

/*!
    \internal
    \class QWidgetBackingStoreTracker
    \brief Class which allows tracking of which widgets are using a given backing store

    QWidgetBackingStoreTracker is a thin wrapper around a QWidgetBackingStore pointer,
    which maintains a list of the QWidgets which are currently using the backing
    store.  This list is modified via the registerWidget and unregisterWidget functions.
 */

QWidgetBackingStoreTracker::QWidgetBackingStoreTracker()
    :   m_ptr(0)
{

}

QWidgetBackingStoreTracker::~QWidgetBackingStoreTracker()
{
    delete m_ptr;
}

/*!
    \internal
    Destroy the contained QWidgetBackingStore, if not null, and clear the list of
    widgets using the backing store, then create a new QWidgetBackingStore, providing
    the QWidget.
 */
void QWidgetBackingStoreTracker::create(QWidget *widget)
{
    destroy();
    m_ptr = new QWidgetBackingStore(widget);
}

/*!
    \internal
    Destroy the contained QWidgetBackingStore, if not null, and clear the list of
    widgets using the backing store.
 */
void QWidgetBackingStoreTracker::destroy()
{
    delete m_ptr;
    m_ptr = 0;
    m_widgets.clear();
}

/*!
    \internal
    Add the widget to the list of widgets currently using the backing store.
    If the widget was already in the list, this function is a no-op.
 */
void QWidgetBackingStoreTracker::registerWidget(QWidget *w)
{
    Q_ASSERT(m_ptr);
    Q_ASSERT(w->internalWinId());
    Q_ASSERT(qt_widget_private(w)->maybeBackingStore() == m_ptr);
    m_widgets.insert(w);
}

/*!
    \internal
    Remove the widget from the list of widgets currently using the backing store.
    If the widget was in the list, and removing it causes the list to be empty,
    the backing store is deleted.
    If the widget was not in the list, this function is a no-op.
 */
void QWidgetBackingStoreTracker::unregisterWidget(QWidget *w)
{
    if (m_widgets.remove(w) && m_widgets.isEmpty()) {
        delete m_ptr;
        m_ptr = 0;
    }
}

/*!
    \internal
    Recursively remove widget and all of its descendents.
 */
void QWidgetBackingStoreTracker::unregisterWidgetSubtree(QWidget *widget)
{
    unregisterWidget(widget);
    foreach (QObject *child, widget->children())
        if (QWidget *childWidget = qobject_cast<QWidget *>(child))
            unregisterWidgetSubtree(childWidget);
}

QWidgetPrivate::QWidgetPrivate(int version)
    : QObjectPrivate(version)
      , extra(0)
      , focus_next(0)
      , focus_prev(0)
      , focus_child(0)
      , layout(0)
      , needsFlush(0)
      , redirectDev(0)
      , widgetItem(0)
      , extraPaintEngine(0)
      , polished(0)
      , graphicsEffect(0)
#if !defined(QT_NO_IM)
      , imHints(Qt::ImhNone)
#endif
      , inheritedFontResolveMask(0)
      , inheritedPaletteResolveMask(0)
      , leftmargin(0)
      , topmargin(0)
      , rightmargin(0)
      , bottommargin(0)
      , leftLayoutItemMargin(0)
      , topLayoutItemMargin(0)
      , rightLayoutItemMargin(0)
      , bottomLayoutItemMargin(0)
      , hd(0)
      , size_policy(QSizePolicy::Preferred, QSizePolicy::Preferred)
      , fg_role(QPalette::NoRole)
      , bg_role(QPalette::NoRole)
      , dirtyOpaqueChildren(1)
      , isOpaque(0)
      , inDirtyList(0)
      , isScrolled(0)
      , isMoved(0)
      , isGLWidget(0)
      , usesDoubleBufferedGLContext(0)
#ifndef QT_NO_IM
      , inheritsInputMethodHints(0)
#endif
#if defined(Q_WS_X11)
      , picture(0)
#elif defined(Q_WS_WIN)
      , noPaintOnScreen(0)
  #ifndef QT_NO_GESTURES
      , nativeGesturePanEnabled(0)
  #endif
#elif defined(Q_WS_MAC)
      , needWindowChange(0)
      , hasAlienChildren(0)
      , window_event(0)
      , qd_hd(0)
#elif defined (Q_WS_QPA)
      , screenNumber(0)
#endif
{
    if (!qApp) {
        qFatal("QWidget: Must construct a QApplication before a QPaintDevice");
        return;
    }

    if (version != QObjectPrivateVersion)
        qFatal("Cannot mix incompatible Qt libraries");

    isWidget = true;
    memset(high_attributes, 0, sizeof(high_attributes));
#if QT_MAC_USE_COCOA
    drawRectOriginalAdded = false;
    originalDrawMethod = true;
    changeMethods = false;
    hasOwnContext = false;
    isInUnifiedToolbar = false;
    unifiedSurface = 0;
#endif // QT_MAC_USE_COCOA
#ifdef QWIDGET_EXTRA_DEBUG
    static int count = 0;
    qDebug() << "widgets" << ++count;
#endif
}


QWidgetPrivate::~QWidgetPrivate()
{
    if (widgetItem)
        widgetItem->wid = 0;

    if (extra)
        deleteExtra();

#ifndef QT_NO_GRAPHICSEFFECT
    delete graphicsEffect;
#endif //QT_NO_GRAPHICSEFFECT
}

class QDummyWindowSurface : public QWindowSurface
{
public:
    QDummyWindowSurface(QWidget *window) : QWindowSurface(window) {}
    QPaintDevice *paintDevice() { return window(); }
    void flush(QWidget *, const QRegion &, const QPoint &) {}
};

QWindowSurface *QWidgetPrivate::createDefaultWindowSurface()
{
    Q_Q(QWidget);

    QWindowSurface *surface;
    if (q->property("_q_DummyWindowSurface").toBool()) {
        surface = new QDummyWindowSurface(q);
    } else {
        if (QApplicationPrivate::graphicsSystem())
            surface = QApplicationPrivate::graphicsSystem()->createWindowSurface(q);
        else
            surface = createDefaultWindowSurface_sys();
    }

    return surface;
}

/*!
    \internal
*/
void QWidgetPrivate::scrollChildren(int dx, int dy)
{
    Q_Q(QWidget);
    if (q->children().size() > 0) {        // scroll children
        QPoint pd(dx, dy);
        QObjectList childObjects = q->children();
        for (int i = 0; i < childObjects.size(); ++i) { // move all children
            QWidget *w = qobject_cast<QWidget*>(childObjects.at(i));
            if (w && !w->isWindow()) {
                QPoint oldp = w->pos();
                QRect  r(w->pos() + pd, w->size());
                w->data->crect = r;
#ifndef Q_WS_QWS
                if (w->testAttribute(Qt::WA_WState_Created))
                    w->d_func()->setWSGeometry();
#endif
                w->d_func()->setDirtyOpaqueRegion();
                QMoveEvent e(r.topLeft(), oldp);
                QApplication::sendEvent(w, &e);
            }
        }
    }
}

QInputContext *QWidgetPrivate::inputContext() const
{
#ifndef QT_NO_IM
    if (ic)
        return ic;
    return qApp->inputContext();
#else
    return 0;
#endif
}

/*!
    This function returns the QInputContext for this widget. By
    default the input context is inherited from the widgets
    parent. For toplevels it is inherited from QApplication.

    You can override this and set a special input context for this
    widget by using the setInputContext() method.

    \sa setInputContext()
*/
QInputContext *QWidget::inputContext()
{
    Q_D(QWidget);
    if (!testAttribute(Qt::WA_InputMethodEnabled))
        return 0;

    return d->inputContext();
}

/*!
  This function sets the input context \a context
  on this widget.

  Qt takes ownership of the given input \a context.

  \sa inputContext()
*/
void QWidget::setInputContext(QInputContext *context)
{
    Q_D(QWidget);
    if (!testAttribute(Qt::WA_InputMethodEnabled))
        return;
#ifndef QT_NO_IM
    if (context == d->ic)
        return;
    if (d->ic)
        delete d->ic;
    d->ic = context;
    if (d->ic)
        d->ic->setParent(this);
#endif
}


/*!
    \obsolete

    This function can be called on the widget that currently has focus
    to reset the input method operating on it.

    This function is providing for convenience, instead you should use
    \l{QInputContext::}{reset()} on the input context that was
    returned by inputContext().

    \sa QInputContext, inputContext(), QInputContext::reset()
*/
void QWidget::resetInputContext()
{
    if (!hasFocus())
        return;
#ifndef QT_NO_IM
    QInputContext *qic = this->inputContext();
    if(qic)
        qic->reset();
#endif // QT_NO_IM
}

#ifdef QT_KEYPAD_NAVIGATION
QPointer<QWidget> QWidgetPrivate::editingWidget;

/*!
    Returns true if this widget currently has edit focus; otherwise false.

    This feature is only available in Qt for Embedded Linux.

    \sa setEditFocus(), QApplication::keypadNavigationEnabled()
*/
bool QWidget::hasEditFocus() const
{
    const QWidget* w = this;
    while (w->d_func()->extra && w->d_func()->extra->focus_proxy)
        w = w->d_func()->extra->focus_proxy;
    return QWidgetPrivate::editingWidget == w;
}

/*!
    \fn void QWidget::setEditFocus(bool enable)

    If \a enable is true, make this widget have edit focus, in which
    case Qt::Key_Up and Qt::Key_Down will be delivered to the widget
    normally; otherwise, Qt::Key_Up and Qt::Key_Down are used to
    change focus.

    This feature is only available in Qt for Embedded Linux and Qt
    for Symbian.

    \sa hasEditFocus(), QApplication::keypadNavigationEnabled()
*/
void QWidget::setEditFocus(bool on)
{
    QWidget *f = this;
    while (f->d_func()->extra && f->d_func()->extra->focus_proxy)
        f = f->d_func()->extra->focus_proxy;

    if (QWidgetPrivate::editingWidget && QWidgetPrivate::editingWidget != f)
        QWidgetPrivate::editingWidget->setEditFocus(false);

    if (on && !f->hasFocus())
        f->setFocus();

    if ((!on && !QWidgetPrivate::editingWidget)
        || (on && QWidgetPrivate::editingWidget == f)) {
        return;
    }

    if (!on && QWidgetPrivate::editingWidget == f) {
        QWidgetPrivate::editingWidget = 0;
        QEvent event(QEvent::LeaveEditFocus);
        QApplication::sendEvent(f, &event);
        QApplication::sendEvent(f->style(), &event);
    } else if (on) {
        QWidgetPrivate::editingWidget = f;
        QEvent event(QEvent::EnterEditFocus);
        QApplication::sendEvent(f, &event);
        QApplication::sendEvent(f->style(), &event);
    }
}
#endif

/*!
    \property QWidget::autoFillBackground
    \brief whether the widget background is filled automatically
    \since 4.1

    If enabled, this property will cause Qt to fill the background of the
    widget before invoking the paint event. The color used is defined by the
    QPalette::Window color role from the widget's \l{QPalette}{palette}.

    In addition, Windows are always filled with QPalette::Window, unless the
    WA_OpaquePaintEvent or WA_NoSystemBackground attributes are set.

    This property cannot be turned off (i.e., set to false) if a widget's
    parent has a static gradient for its background.

    \warning Use this property with caution in conjunction with
    \l{Qt Style Sheets}. When a widget has a style sheet with a valid
    background or a border-image, this property is automatically disabled.

    By default, this property is false.

    \sa Qt::WA_OpaquePaintEvent, Qt::WA_NoSystemBackground,
    {QWidget#Transparency and Double Buffering}{Transparency and Double Buffering}
*/
bool QWidget::autoFillBackground() const
{
    Q_D(const QWidget);
    return d->extra && d->extra->autoFillBackground;
}

void QWidget::setAutoFillBackground(bool enabled)
{
    Q_D(QWidget);
    if (!d->extra)
        d->createExtra();
    if (d->extra->autoFillBackground == enabled)
        return;

    d->extra->autoFillBackground = enabled;
    d->updateIsOpaque();
    update();
    d->updateIsOpaque();
}

/*!
    \class QWidget
    \brief The QWidget class is the base class of all user interface objects.

    \ingroup basicwidgets


    The widget is the atom of the user interface: it receives mouse, keyboard
    and other events from the window system, and paints a representation of
    itself on the screen. Every widget is rectangular, and they are sorted in a
    Z-order. A widget is clipped by its parent and by the widgets in front of
    it.

    A widget that is not embedded in a parent widget is called a window.
    Usually, windows have a frame and a title bar, although it is also possible
    to create windows without such decoration using suitable
    \l{Qt::WindowFlags}{window flags}). In Qt, QMainWindow and the various
    subclasses of QDialog are the most common window types.

    Every widget's constructor accepts one or two standard arguments:

    \list 1
        \i  \c{QWidget *parent = 0} is the parent of the new widget. If it is 0
            (the default), the new widget will be a window. If not, it will be
            a child of \e parent, and be constrained by \e parent's geometry
            (unless you specify Qt::Window as window flag).
        \i  \c{Qt::WindowFlags f = 0} (where available) sets the window flags;
            the default is suitable for almost all widgets, but to get, for
            example, a window without a window system frame, you must use
            special flags.
    \endlist

    QWidget has many member functions, but some of them have little direct
    functionality; for example, QWidget has a font property, but never uses
    this itself. There are many subclasses which provide real functionality,
    such as QLabel, QPushButton, QListWidget, and QTabWidget.


    \section1 Top-Level and Child Widgets

    A widget without a parent widget is always an independent window (top-level
    widget). For these widgets, setWindowTitle() and setWindowIcon() set the
    title bar and icon respectively.

    Non-window widgets are child widgets, displayed within their parent
    widgets. Most widgets in Qt are mainly useful as child widgets. For
    example, it is possible to display a button as a top-level window, but most
    people prefer to put their buttons inside other widgets, such as QDialog.

    \image parent-child-widgets.png A parent widget containing various child widgets.

    The diagram above shows a QGroupBox widget being used to hold various child
    widgets in a layout provided by QGridLayout. The QLabel child widgets have
    been outlined to indicate their full sizes.

    If you want to use a QWidget to hold child widgets you will usually want to
    add a layout to the parent QWidget. See \l{Layout Management} for more
    information.


    \section1 Composite Widgets

    When a widget is used as a container to group a number of child widgets, it
    is known as a composite widget. These can be created by constructing a
    widget with the required visual properties - a QFrame, for example - and
    adding child widgets to it, usually managed by a layout. The above diagram
    shows such a composite widget that was created using \l{Qt Designer}.

    Composite widgets can also be created by subclassing a standard widget,
    such as QWidget or QFrame, and adding the necessary layout and child
    widgets in the constructor of the subclass. Many of the \l{Qt Examples}
    {examples provided with Qt} use this approach, and it is also covered in
    the Qt \l{Tutorials}.


    \section1 Custom Widgets and Painting

    Since QWidget is a subclass of QPaintDevice, subclasses can be used to
    display custom content that is composed using a series of painting
    operations with an instance of the QPainter class. This approach contrasts
    with the canvas-style approach used by the \l{Graphics View}
    {Graphics View Framework} where items are added to a scene by the
    application and are rendered by the framework itself.

    Each widget performs all painting operations from within its paintEvent()
    function. This is called whenever the widget needs to be redrawn, either
    as a result of some external change or when requested by the application.

    The \l{widgets/analogclock}{Analog Clock example} shows how a simple widget
    can handle paint events.


    \section1 Size Hints and Size Policies

    When implementing a new widget, it is almost always useful to reimplement
    sizeHint() to provide a reasonable default size for the widget and to set
    the correct size policy with setSizePolicy().

    By default, composite widgets which do not provide a size hint will be
    sized according to the space requirements of their child widgets.

    The size policy lets you supply good default behavior for the layout
    management system, so that other widgets can contain and manage yours
    easily. The default size policy indicates that the size hint represents
    the preferred size of the widget, and this is often good enough for many
    widgets.

    \note The size of top-level widgets are constrained to 2/3 of the desktop's
    height and width. You can resize() the widget manually if these bounds are
    inadequate.


    \section1 Events

    Widgets respond to events that are typically caused by user actions. Qt
    delivers events to widgets by calling specific event handler functions with
    instances of QEvent subclasses containing information about each event.

    If your widget only contains child widgets, you probably do not need to
    implement any event handlers. If you want to detect a mouse click in a
    child widget call the child's underMouse() function inside the widget's
    mousePressEvent().

    The \l{widgets/scribble}{Scribble example} implements a wider set of
    events to handle mouse movement, button presses, and window resizing.

    You will need to supply the behavior and content for your own widgets, but
    here is a brief overview of the events that are relevant to QWidget,
    starting with the most common ones:

    \list
        \i  paintEvent() is called whenever the widget needs to be repainted.
            Every widget displaying custom content must implement it. Painting
            using a QPainter can only take place in a paintEvent() or a
            function called by a paintEvent().
        \i  resizeEvent() is called when the widget has been resized.
        \i  mousePressEvent() is called when a mouse button is pressed while
            the mouse cursor is inside the widget, or when the widget has
            grabbed the mouse using grabMouse(). Pressing the mouse without
            releasing it is effectively the same as calling grabMouse().
        \i  mouseReleaseEvent() is called when a mouse button is released. A
            widget receives mouse release events when it has received the
            corresponding mouse press event. This means that if the user
            presses the mouse inside \e your widget, then drags the mouse
            somewhere else before releasing the mouse button, \e your widget
            receives the release event. There is one exception: if a popup menu
            appears while the mouse button is held down, this popup immediately
            steals the mouse events.
        \i  mouseDoubleClickEvent() is called when the user double-clicks in
            the widget. If the user double-clicks, the widget receives a mouse
            press event, a mouse release event and finally this event instead
            of a second mouse press event. (Some mouse move events may also be
            received if the mouse is not held steady during this operation.) It
            is \e{not possible} to distinguish a click from a double-click
            until the second click arrives. (This is one reason why most GUI
            books recommend that double-clicks be an extension of
            single-clicks, rather than trigger a different action.)
    \endlist

    Widgets that accept keyboard input need to reimplement a few more event
    handlers:

    \list
        \i  keyPressEvent() is called whenever a key is pressed, and again when
            a key has been held down long enough for it to auto-repeat. The
            \key Tab and \key Shift+Tab keys are only passed to the widget if
            they are not used by the focus-change mechanisms. To force those
            keys to be processed by your widget, you must reimplement
            QWidget::event().
        \i  focusInEvent() is called when the widget gains keyboard focus
            (assuming you have called setFocusPolicy()). Well-behaved widgets
            indicate that they own the keyboard focus in a clear but discreet
            way.
        \i  focusOutEvent() is called when the widget loses keyboard focus.
    \endlist

    You may be required to also reimplement some of the less common event
    handlers:

    \list
        \i  mouseMoveEvent() is called whenever the mouse moves while a mouse
            button is held down. This can be useful during drag and drop
            operations. If you call \l{setMouseTracking()}{setMouseTracking}(true),
            you get mouse move events even when no buttons are held down.
            (See also the \l{Drag and Drop} guide.)
        \i  keyReleaseEvent() is called whenever a key is released and while it
            is held down (if the key is auto-repeating). In that case, the
            widget will receive a pair of key release and key press event for
            every repeat. The \key Tab and \key Shift+Tab keys are only passed
            to the widget if they are not used by the focus-change mechanisms.
            To force those keys to be processed by your widget, you must
            reimplement QWidget::event().
        \i  wheelEvent() is called whenever the user turns the mouse wheel
            while the widget has the focus.
        \i  enterEvent() is called when the mouse enters the widget's screen
            space. (This excludes screen space owned by any of the widget's
            children.)
        \i  leaveEvent() is called when the mouse leaves the widget's screen
            space. If the mouse enters a child widget it will not cause a
            leaveEvent().
        \i  moveEvent() is called when the widget has been moved relative to
            its parent.
        \i  closeEvent() is called when the user closes the widget (or when
            close() is called).
    \endlist

    There are also some rather obscure events described in the documentation
    for QEvent::Type. To handle these events, you need to reimplement event()
    directly.

    The default implementation of event() handles \key Tab and \key Shift+Tab
    (to move the keyboard focus), and passes on most of the other events to
    one of the more specialized handlers above.

    Events and the mechanism used to deliver them are covered in 
    \l{The Event System}.

    \section1 Groups of Functions and Properties

    \table
    \header \i Context \i Functions and Properties

    \row \i Window functions \i
        show(),
        hide(),
        raise(),
        lower(),
        close().

    \row \i Top-level windows \i
        \l windowModified, \l windowTitle, \l windowIcon, \l windowIconText,
        \l isActiveWindow, activateWindow(), \l minimized, showMinimized(),
        \l maximized, showMaximized(), \l fullScreen, showFullScreen(),
        showNormal().

    \row \i Window contents \i
        update(),
        repaint(),
        scroll().

    \row \i Geometry \i
        \l pos, x(), y(), \l rect, \l size, width(), height(), move(), resize(),
        \l sizePolicy, sizeHint(), minimumSizeHint(),
        updateGeometry(), layout(),
        \l frameGeometry, \l geometry, \l childrenRect, \l childrenRegion,
        adjustSize(),
        mapFromGlobal(), mapToGlobal(),
        mapFromParent(), mapToParent(),
        \l maximumSize, \l minimumSize, \l sizeIncrement,
        \l baseSize, setFixedSize()

    \row \i Mode \i
        \l visible, isVisibleTo(),
        \l enabled, isEnabledTo(),
        \l modal,
        isWindow(),
        \l mouseTracking,
        \l updatesEnabled,
        visibleRegion().

    \row \i Look and feel \i
        style(),
        setStyle(),
        \l styleSheet,
        \l cursor,
        \l font,
        \l palette,
        backgroundRole(), setBackgroundRole(),
        fontInfo(), fontMetrics().

    \row \i Keyboard focus functions \i
        \l focus, \l focusPolicy,
        setFocus(), clearFocus(), setTabOrder(), setFocusProxy(),
        focusNextChild(), focusPreviousChild().

    \row \i Mouse and keyboard grabbing \i
        grabMouse(), releaseMouse(),
        grabKeyboard(), releaseKeyboard(),
        mouseGrabber(), keyboardGrabber().

    \row \i Event handlers \i
        event(),
        mousePressEvent(),
        mouseReleaseEvent(),
        mouseDoubleClickEvent(),
        mouseMoveEvent(),
        keyPressEvent(),
        keyReleaseEvent(),
        focusInEvent(),
        focusOutEvent(),
        wheelEvent(),
        enterEvent(),
        leaveEvent(),
        paintEvent(),
        moveEvent(),
        resizeEvent(),
        closeEvent(),
        dragEnterEvent(),
        dragMoveEvent(),
        dragLeaveEvent(),
        dropEvent(),
        childEvent(),
        showEvent(),
        hideEvent(),
        customEvent().
        changeEvent(),

    \row \i System functions \i
        parentWidget(), window(), setParent(), winId(),
        find(), metric().

    \row \i Interactive help \i
        setToolTip(), setWhatsThis()

    \endtable


    \section1 Widget Style Sheets

    In addition to the standard widget styles for each platform, widgets can
    also be styled according to rules specified in a \l{styleSheet}
    {style sheet}. This feature enables you to customize the appearance of
    specific widgets to provide visual cues to users about their purpose. For
    example, a button could be styled in a particular way to indicate that it
    performs a destructive action.

    The use of widget style sheets is described in more detail in the
    \l{Qt Style Sheets} document.


    \section1 Transparency and Double Buffering

    Since Qt 4.0, QWidget automatically double-buffers its painting, so there
    is no need to write double-buffering code in paintEvent() to avoid
    flicker.

    Since Qt 4.1, the Qt::WA_ContentsPropagated widget attribute has been
    deprecated. Instead, the contents of parent widgets are propagated by
    default to each of their children as long as Qt::WA_PaintOnScreen is not
    set. Custom widgets can be written to take advantage of this feature by
    updating irregular regions (to create non-rectangular child widgets), or
    painting with colors that have less than full alpha component. The
    following diagram shows how attributes and properties of a custom widget
    can be fine-tuned to achieve different effects.

    \image propagation-custom.png

    In the above diagram, a semi-transparent rectangular child widget with an
    area removed is constructed and added to a parent widget (a QLabel showing
    a pixmap). Then, different properties and widget attributes are set to
    achieve different effects:

    \list
        \i  The left widget has no additional properties or widget attributes
            set. This default state suits most custom widgets using
            transparency, are irregularly-shaped, or do not paint over their
            entire area with an opaque brush.
        \i  The center widget has the \l autoFillBackground property set. This
            property is used with custom widgets that rely on the widget to
            supply a default background, and do not paint over their entire
            area with an opaque brush.
        \i  The right widget has the Qt::WA_OpaquePaintEvent widget attribute
            set. This indicates that the widget will paint over its entire area
            with opaque colors. The widget's area will initially be
            \e{uninitialized}, represented in the diagram with a red diagonal
            grid pattern that shines through the overpainted area. The
            Qt::WA_OpaquePaintArea attribute is useful for widgets that need to
            paint their own specialized contents quickly and do not need a
            default filled background.
    \endlist

    To rapidly update custom widgets with simple background colors, such as
    real-time plotting or graphing widgets, it is better to define a suitable
    background color (using setBackgroundRole() with the
    QPalette::Window role), set the \l autoFillBackground property, and only
    implement the necessary drawing functionality in the widget's paintEvent().

    To rapidly update custom widgets that constantly paint over their entire
    areas with opaque content, e.g., video streaming widgets, it is better to
    set the widget's Qt::WA_OpaquePaintEvent, avoiding any unnecessary overhead
    associated with repainting the widget's background.

    If a widget has both the Qt::WA_OpaquePaintEvent widget attribute \e{and}
    the \l autoFillBackground property set, the Qt::WA_OpaquePaintEvent
    attribute takes precedence. Depending on your requirements, you should
    choose either one of them.

    Since Qt 4.1, the contents of parent widgets are also propagated to
    standard Qt widgets. This can lead to some unexpected results if the
    parent widget is decorated in a non-standard way, as shown in the diagram
    below.

    \image propagation-standard.png

    The scope for customizing the painting behavior of standard Qt widgets,
    without resorting to subclassing, is slightly less than that possible for
    custom widgets. Usually, the desired appearance of a standard widget can be
    achieved by setting its \l autoFillBackground property.


    \section1 Creating Translucent Windows

    Since Qt 4.5, it has been possible to create windows with translucent regions
    on window systems that support compositing.

    To enable this feature in a top-level widget, set its Qt::WA_TranslucentBackground
    attribute with setAttribute() and ensure that its background is painted with
    non-opaque colors in the regions you want to be partially transparent.

    Platform notes:

    \list
    \o X11: This feature relies on the use of an X server that supports ARGB visuals
    and a compositing window manager.
    \o Windows: The widget needs to have the Qt::FramelessWindowHint window flag set
    for the translucency to work.
    \endlist


    \section1 Native Widgets vs Alien Widgets

    Introduced in Qt 4.4, alien widgets are widgets unknown to the windowing
    system. They do not have a native window handle associated with them. This
    feature significantly speeds up widget painting, resizing, and removes flicker.

    Should you require the old behavior with native windows, you can choose
    one of the following options:

    \list 1
        \i  Use the \c{QT_USE_NATIVE_WINDOWS=1} in your environment.
        \i  Set the Qt::AA_NativeWindows attribute on your application. All
            widgets will be native widgets.
        \i  Set the Qt::WA_NativeWindow attribute on widgets: The widget itself
            and all of its ancestors will become native (unless
            Qt::WA_DontCreateNativeAncestors is set).
        \i  Call QWidget::winId to enforce a native window (this implies 3).
        \i  Set the Qt::WA_PaintOnScreen attribute to enforce a native window
            (this implies 3).
    \endlist

    \sa QEvent, QPainter, QGridLayout, QBoxLayout

    \section1 Softkeys

    Since Qt 4.6, Softkeys are usually physical keys on a device that have a corresponding label or
    other visual representation on the screen that is generally located next to its
    physical counterpart. They are most often found on mobile phone platforms. In
    modern touch based user interfaces it is also possible to have softkeys that do
    not correspond to any physical keys. Softkeys differ from other onscreen labels
    in that they are contextual.

    In Qt, contextual softkeys are added to a widget by calling addAction() and
    passing a \c QAction with a softkey role set on it. When the widget
    containing the softkey actions has focus, its softkeys should appear in
    the user interface. Softkeys are discovered by traversing the widget
    hierarchy so it is possible to define a single set of softkeys that are
    present at all times by calling addAction() for a given top level widget.

    On some platforms, this concept overlaps with \c QMenuBar such that if no
    other softkeys are found and the top level widget is a QMainWindow containing
    a QMenuBar, the menubar actions may appear on one of the softkeys.

    Note: Currently softkeys are only supported on the Symbian Platform.

    \sa addAction(), QAction, QMenuBar

*/

QWidgetMapper *QWidgetPrivate::mapper = 0;          // widget with wid
QWidgetSet *QWidgetPrivate::allWidgets = 0;         // widgets with no wid


/*****************************************************************************
  QWidget utility functions
 *****************************************************************************/

QRegion qt_dirtyRegion(QWidget *widget)
{
    if (!widget)
        return QRegion();

    QWidgetBackingStore *bs = qt_widget_private(widget)->maybeBackingStore();
    if (!bs)
        return QRegion();

    return bs->dirtyRegion(widget);
}

/*****************************************************************************
  QWidget member functions
 *****************************************************************************/

/*
    Widget state flags:
  \list
  \i Qt::WA_WState_Created The widget has a valid winId().
  \i Qt::WA_WState_Visible The widget is currently visible.
  \i Qt::WA_WState_Hidden The widget is hidden, i.e. it won't
  become visible unless you call show() on it. Qt::WA_WState_Hidden
  implies !Qt::WA_WState_Visible.
  \i Qt::WA_WState_CompressKeys Compress keyboard events.
  \i Qt::WA_WState_BlockUpdates Repaints and updates are disabled.
  \i Qt::WA_WState_InPaintEvent Currently processing a paint event.
  \i Qt::WA_WState_Reparented The widget has been reparented.
  \i Qt::WA_WState_ConfigPending A configuration (resize/move) event is pending.
  \i Qt::WA_WState_DND (Deprecated) The widget supports drag and drop, see setAcceptDrops().
  \endlist
*/

struct QWidgetExceptionCleaner
{
    /* this cleans up when the constructor throws an exception */
    static inline void cleanup(QWidget *that, QWidgetPrivate *d)
    {
#ifdef QT_NO_EXCEPTIONS
        Q_UNUSED(that);
        Q_UNUSED(d);
#else
        QWidgetPrivate::allWidgets->remove(that);
        if (d->focus_next != that) {
            if (d->focus_next)
                d->focus_next->d_func()->focus_prev = d->focus_prev;
            if (d->focus_prev)
                d->focus_prev->d_func()->focus_next = d->focus_next;
        }
#endif
    }
};

/*!
    Constructs a widget which is a child of \a parent, with  widget
    flags set to \a f.

    If \a parent is 0, the new widget becomes a window. If
    \a parent is another widget, this widget becomes a child window
    inside \a parent. The new widget is deleted when its \a parent is
    deleted.

    The widget flags argument, \a f, is normally 0, but it can be set
    to customize the frame of a window (i.e. \a
    parent must be 0). To customize the frame, use a value composed
    from the bitwise OR of any of the \l{Qt::WindowFlags}{window flags}.

    If you add a child widget to an already visible widget you must
    explicitly show the child to make it visible.

    Note that the X11 version of Qt may not be able to deliver all
    combinations of style flags on all systems. This is because on
    X11, Qt can only ask the window manager, and the window manager
    can override the application's settings. On Windows, Qt can set
    whatever flags you want.

    \sa windowFlags
*/
QWidget::QWidget(QWidget *parent, Qt::WindowFlags f)
    : QObject(*new QWidgetPrivate, 0), QPaintDevice()
{
    QT_TRY {
        d_func()->init(parent, f);
    } QT_CATCH(...) {
        QWidgetExceptionCleaner::cleanup(this, d_func());
        QT_RETHROW;
    }
}

#ifdef QT3_SUPPORT
/*!
    \overload
    \obsolete
 */
QWidget::QWidget(QWidget *parent, const char *name, Qt::WindowFlags f)
    : QObject(*new QWidgetPrivate, 0), QPaintDevice()
{
    QT_TRY {
        d_func()->init(parent , f);
        setObjectName(QString::fromAscii(name));
    } QT_CATCH(...) {
        QWidgetExceptionCleaner::cleanup(this, d_func());
        QT_RETHROW;
    }
}
#endif

/*! \internal
*/
QWidget::QWidget(QWidgetPrivate &dd, QWidget* parent, Qt::WindowFlags f)
    : QObject(dd, 0), QPaintDevice()
{
    Q_D(QWidget);
    QT_TRY {
        d->init(parent, f);
    } QT_CATCH(...) {
        QWidgetExceptionCleaner::cleanup(this, d_func());
        QT_RETHROW;
    }
}

/*!
    \internal
*/
int QWidget::devType() const
{
    return QInternal::Widget;
}


//### w is a "this" ptr, passed as a param because QWorkspace needs special logic
void QWidgetPrivate::adjustFlags(Qt::WindowFlags &flags, QWidget *w)
{
    bool customize =  (flags & (Qt::CustomizeWindowHint
            | Qt::FramelessWindowHint
            | Qt::WindowTitleHint
            | Qt::WindowSystemMenuHint
            | Qt::WindowMinimizeButtonHint
            | Qt::WindowMaximizeButtonHint
            | Qt::WindowCloseButtonHint
            | Qt::WindowContextHelpButtonHint));

    uint type = (flags & Qt::WindowType_Mask);

    if ((type == Qt::Widget || type == Qt::SubWindow) && w && !w->parent()) {
        type = Qt::Window;
        flags |= Qt::Window;
    }

    if (flags & Qt::CustomizeWindowHint) {
        // modify window flags to make them consistent.
        // Only enable this on non-Mac platforms. Since the old way of doing this would
        // interpret WindowSystemMenuHint as a close button and we can't change that behavior
        // we can't just add this in.
#ifndef Q_WS_MAC
        if (flags & (Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint | Qt::WindowContextHelpButtonHint)) {
            flags |= Qt::WindowSystemMenuHint;
#else
        if (flags & (Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint
                     | Qt::WindowSystemMenuHint)) {
#endif
            flags |= Qt::WindowTitleHint;
            flags &= ~Qt::FramelessWindowHint;
        }
    } else if (customize && !(flags & Qt::FramelessWindowHint)) {
        // if any of the window hints that affect the titlebar are set
        // and the window is supposed to have frame, we add a titlebar
        // and system menu by default.
        flags |= Qt::WindowSystemMenuHint;
        flags |= Qt::WindowTitleHint;
    }
    if (customize)
        ; // don't modify window flags if the user explicitly set them.
    else if (type == Qt::Dialog || type == Qt::Sheet)
#ifndef Q_WS_WINCE
        flags |= Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowContextHelpButtonHint | Qt::WindowCloseButtonHint;
#else
        flags |= Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowCloseButtonHint;
#endif
    else if (type == Qt::Tool)
        flags |= Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowCloseButtonHint;
    else
        flags |= Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowMinimizeButtonHint | Qt::WindowMaximizeButtonHint | Qt::WindowCloseButtonHint;


}

void QWidgetPrivate::init(QWidget *parentWidget, Qt::WindowFlags f)
{
    Q_Q(QWidget);
    if (QApplication::type() == QApplication::Tty)
        qFatal("QWidget: Cannot create a QWidget when no GUI is being used");

    Q_ASSERT(allWidgets);
    if (allWidgets)
        allWidgets->insert(q);

    QWidget *desktopWidget = 0;
    if (parentWidget && parentWidget->windowType() == Qt::Desktop) {
        desktopWidget = parentWidget;
        parentWidget = 0;
    }

    q->data = &data;

#ifndef QT_NO_THREAD
    if (!parent) {
        Q_ASSERT_X(q->thread() == qApp->thread(), "QWidget",
                   "Widgets must be created in the GUI thread.");
    }
#endif

#if defined(Q_WS_X11)
    if (desktopWidget) {
        // make sure the widget is created on the same screen as the
        // programmer specified desktop widget
        xinfo = desktopWidget->d_func()->xinfo;
    }
#elif defined(Q_WS_QPA)
    if (desktopWidget) {
        int screen = desktopWidget->d_func()->screenNumber;
        QPlatformIntegration *platform = QApplicationPrivate::platformIntegration();
        platform->moveToScreen(q, screen);
    }
#else
    Q_UNUSED(desktopWidget);
#endif

    data.fstrut_dirty = true;

    data.winid = 0;
    data.widget_attributes = 0;
    data.window_flags = f;
    data.window_state = 0;
    data.focus_policy = 0;
    data.context_menu_policy = Qt::DefaultContextMenu;
    data.window_modality = Qt::NonModal;

    data.sizehint_forced = 0;
    data.is_closing = 0;
    data.in_show = 0;
    data.in_set_window_state = 0;
    data.in_destructor = false;

    // Widgets with Qt::MSWindowsOwnDC (typically QGLWidget) must have a window handle.
    if (f & Qt::MSWindowsOwnDC)
        q->setAttribute(Qt::WA_NativeWindow);

#ifdef Q_WS_MAC
    q->setAttribute(Qt::WA_NativeWindow);
#endif

    q->setAttribute(Qt::WA_QuitOnClose); // might be cleared in adjustQuitOnCloseAttribute()
    adjustQuitOnCloseAttribute();

    q->setAttribute(Qt::WA_WState_Hidden);

    //give potential windows a bigger "pre-initial" size; create_sys() will give them a new size later
#ifdef Q_OS_SYMBIAN
    if (isGLWidget) {
        // Don't waste GPU mem for unnecessary large egl surface
        data.crect = QRect(0,0,2,2);
    } else {
        data.crect = parentWidget ? QRect(0,0,100,30) : QRect(0,0,360,640);
    }
#else
    data.crect = parentWidget ? QRect(0,0,100,30) : QRect(0,0,640,480);
#endif

    focus_next = focus_prev = q;

    if ((f & Qt::WindowType_Mask) == Qt::Desktop)
        q->create();
    else if (parentWidget)
        q->setParent(parentWidget, data.window_flags);
    else {
        adjustFlags(data.window_flags, q);
        resolveLayoutDirection();
        // opaque system background?
        const QBrush &background = q->palette().brush(QPalette::Window);
        setOpaque(q->isWindow() && background.style() != Qt::NoBrush && background.isOpaque());
    }
    data.fnt = QFont(data.fnt, q);
#if defined(Q_WS_X11)
    data.fnt.x11SetScreen(xinfo.screen());
#endif // Q_WS_X11

    q->setAttribute(Qt::WA_PendingMoveEvent);
    q->setAttribute(Qt::WA_PendingResizeEvent);

    if (++QWidgetPrivate::instanceCounter > QWidgetPrivate::maxInstances)
        QWidgetPrivate::maxInstances = QWidgetPrivate::instanceCounter;

    if (QApplicationPrivate::app_compile_version < 0x040200
        || QApplicationPrivate::testAttribute(Qt::AA_ImmediateWidgetCreation))
        q->create();


    QEvent e(QEvent::Create);
    QApplication::sendEvent(q, &e);
    QApplication::postEvent(q, new QEvent(QEvent::PolishRequest));

    extraPaintEngine = 0;
}



void QWidgetPrivate::createRecursively()
{
    Q_Q(QWidget);
    q->create(0, true, true);
    for (int i = 0; i < children.size(); ++i) {
        QWidget *child = qobject_cast<QWidget *>(children.at(i));
        if (child && !child->isHidden() && !child->isWindow() && !child->testAttribute(Qt::WA_WState_Created))
            child->d_func()->createRecursively();
    }
}




/*!
    Creates a new widget window if \a window is 0, otherwise sets the
    widget's window to \a window.

    Initializes the window (sets the geometry etc.) if \a
    initializeWindow is true. If \a initializeWindow is false, no
    initialization is performed. This parameter only makes sense if \a
    window is a valid window.

    Destroys the old window if \a destroyOldWindow is true. If \a
    destroyOldWindow is false, you are responsible for destroying the
    window yourself (using platform native code).

    The QWidget constructor calls create(0,true,true) to create a
    window for this widget.
*/

void QWidget::create(WId window, bool initializeWindow, bool destroyOldWindow)
{
    Q_D(QWidget);
    if (testAttribute(Qt::WA_WState_Created) && window == 0 && internalWinId())
        return;

    if (d->data.in_destructor)
        return;

    Qt::WindowType type = windowType();
    Qt::WindowFlags &flags = data->window_flags;

    if ((type == Qt::Widget || type == Qt::SubWindow) && !parentWidget()) {
        type = Qt::Window;
        flags |= Qt::Window;
    }

#ifndef Q_WS_QPA
    if (QWidget *parent = parentWidget()) {
#ifdef Q_WS_MAC
        if (testAttribute(Qt::WA_NativeWindow) == false)
            parent->d_func()->hasAlienChildren = true;
#endif
        if (type & Qt::Window) {
            if (!parent->testAttribute(Qt::WA_WState_Created))
                parent->createWinId();
        } else if (testAttribute(Qt::WA_NativeWindow) && !parent->internalWinId()
                   && !testAttribute(Qt::WA_DontCreateNativeAncestors)) {
            // We're about to create a native child widget that doesn't have a native parent;
            // enforce a native handle for the parent unless the Qt::WA_DontCreateNativeAncestors
            // attribute is set.
            d->createWinId(window);
            // Nothing more to do.
            Q_ASSERT(testAttribute(Qt::WA_WState_Created));
            Q_ASSERT(internalWinId());
            return;
        }
    }
#endif //Q_WS_QPA

#ifdef QT3_SUPPORT
    if (flags & Qt::WStaticContents)
        setAttribute(Qt::WA_StaticContents);
    if (flags & Qt::WDestructiveClose)
        setAttribute(Qt::WA_DeleteOnClose);
    if (flags & Qt::WShowModal)
        setWindowModality(Qt::ApplicationModal);
    if (flags & Qt::WMouseNoMask)
        setAttribute(Qt::WA_MouseNoMask);
    if (flags & Qt::WGroupLeader)
        setAttribute(Qt::WA_GroupLeader);
    if (flags & Qt::WNoMousePropagation)
        setAttribute(Qt::WA_NoMousePropagation);
#endif

    static int paintOnScreenEnv = -1;
    if (paintOnScreenEnv == -1)
        paintOnScreenEnv = qgetenv("QT_ONSCREEN_PAINT").toInt() > 0 ? 1 : 0;
    if (paintOnScreenEnv == 1)
        setAttribute(Qt::WA_PaintOnScreen);

    if (QApplicationPrivate::testAttribute(Qt::AA_NativeWindows))
        setAttribute(Qt::WA_NativeWindow);

#ifdef ALIEN_DEBUG
    qDebug() << "QWidget::create:" << this << "parent:" << parentWidget()
             << "Alien?" << !testAttribute(Qt::WA_NativeWindow);
#endif

#if defined (Q_WS_WIN) && !defined(QT_NO_DRAGANDDROP)
    // Unregister the dropsite (if already registered) before we
    // re-create the widget with a native window.
    if (testAttribute(Qt::WA_WState_Created) && !internalWinId() && testAttribute(Qt::WA_NativeWindow)
            && d->extra && d->extra->dropTarget) {
        d->registerDropSite(false);
    }
#endif // defined (Q_WS_WIN) && !defined(QT_NO_DRAGANDDROP)

    d->updateIsOpaque();

    setAttribute(Qt::WA_WState_Created);                        // set created flag
    d->create_sys(window, initializeWindow, destroyOldWindow);

    // a real toplevel window needs a backing store
    if (isWindow() && windowType() != Qt::Desktop) {
        d->topData()->backingStore.destroy();
        if (hasBackingStoreSupport())
            d->topData()->backingStore.create(this);
    }

    d->setModal_sys();

    if (!isWindow() && parentWidget() && parentWidget()->testAttribute(Qt::WA_DropSiteRegistered))
        setAttribute(Qt::WA_DropSiteRegistered, true);

#ifdef QT_EVAL
    extern void qt_eval_init_widget(QWidget *w);
    qt_eval_init_widget(this);
#endif

    // need to force the resting of the icon after changing parents
    if (testAttribute(Qt::WA_SetWindowIcon))
        d->setWindowIcon_sys(true);
    if (isWindow() && !d->topData()->iconText.isEmpty())
        d->setWindowIconText_helper(d->topData()->iconText);
    if (isWindow() && !d->topData()->caption.isEmpty())
        d->setWindowTitle_helper(d->topData()->caption);
    if (windowType() != Qt::Desktop) {
        d->updateSystemBackground();

        if (isWindow() && !testAttribute(Qt::WA_SetWindowIcon))
            d->setWindowIcon_sys();
    }
}

/*!
    Destroys the widget.

    All this widget's children are deleted first. The application
    exits if this widget is the main widget.
*/

QWidget::~QWidget()
{
    Q_D(QWidget);
    d->data.in_destructor = true;

#if defined (QT_CHECK_STATE)
    if (paintingActive())
        qWarning("QWidget: %s (%s) deleted while being painted", className(), name());
#endif

#ifndef QT_NO_GESTURES
    foreach (Qt::GestureType type, d->gestureContext.keys())
        ungrabGesture(type);
#endif

    // force acceptDrops false before winId is destroyed.
    d->registerDropSite(false);

#ifndef QT_NO_ACTION
    // remove all actions from this widget
    for (int i = 0; i < d->actions.size(); ++i) {
        QActionPrivate *apriv = d->actions.at(i)->d_func();
        apriv->widgets.removeAll(this);
    }
    d->actions.clear();
#endif

#ifndef QT_NO_SHORTCUT
    // Remove all shortcuts grabbed by this
    // widget, unless application is closing
    if (!QApplicationPrivate::is_app_closing && testAttribute(Qt::WA_GrabbedShortcut))
        qApp->d_func()->shortcutMap.removeShortcut(0, this, QKeySequence());
#endif

    // delete layout while we still are a valid widget
    delete d->layout;
    // Remove myself from focus list

    Q_ASSERT(d->focus_next->d_func()->focus_prev == this);
    Q_ASSERT(d->focus_prev->d_func()->focus_next == this);

    if (d->focus_next != this) {
        d->focus_next->d_func()->focus_prev = d->focus_prev;
        d->focus_prev->d_func()->focus_next = d->focus_next;
        d->focus_next = d->focus_prev = 0;
    }

#ifdef QT3_SUPPORT
    if (QApplicationPrivate::main_widget == this) {        // reset main widget
        QApplicationPrivate::main_widget = 0;
        QApplication::quit();
    }
#endif

    QT_TRY {
        clearFocus();
    } QT_CATCH(...) {
        // swallow this problem because we are in a destructor
    }

    d->setDirtyOpaqueRegion();

    if (isWindow() && isVisible() && internalWinId()) {
        QT_TRY {
            d->close_helper(QWidgetPrivate::CloseNoEvent);
        } QT_CATCH(...) {
            // if we're out of memory, at least hide the window.
            QT_TRY {
                hide();
            } QT_CATCH(...) {
                // and if that also doesn't work, then give up
            }
        }
    }

#if defined(Q_WS_WIN) || defined(Q_WS_X11)|| defined(Q_WS_MAC)
    else if (!internalWinId() && isVisible()) {
        qApp->d_func()->sendSyntheticEnterLeave(this);
    }
#elif defined(Q_WS_QWS) || defined(Q_WS_QPA)
    else if (isVisible()) {
        qApp->d_func()->sendSyntheticEnterLeave(this);
    }
#endif

#ifdef Q_OS_SYMBIAN
    if (d->extra && d->extra->topextra && d->extra->topextra->backingStore) {
        // Okay, we are about to destroy the top-level window that owns
        // the backing store. Make sure we delete the backing store right away
        // before the window handle is invalid. This is important because
        // the backing store will delete its window surface, which may or may
        // not have a reference to this widget that will be used later to
        // notify the window it no longer has a surface.
        d->extra->topextra->backingStore.destroy();
    }
#endif
    if (QWidgetBackingStore *bs = d->maybeBackingStore()) {
        bs->removeDirtyWidget(this);
        if (testAttribute(Qt::WA_StaticContents))
            bs->removeStaticWidget(this);
    }

    delete d->needsFlush;
    d->needsFlush = 0;

    // set all QPointers for this object to zero
    if (d->hasGuards)
        QObjectPrivate::clearGuards(this);

    if (d->declarativeData) {
        QAbstractDeclarativeData::destroyed(d->declarativeData, this);
        d->declarativeData = 0;                 // don't activate again in ~QObject
    }

#ifdef QT_MAC_USE_COCOA
    // QCocoaView holds a pointer back to this widget. Clear it now
    // to make sure it's not followed later on. The lifetime of the
    // QCocoaView might exceed the lifetime of this widget in cases
    // where Cocoa itself holds references to it.
    extern void qt_mac_clearCocoaViewQWidgetPointers(QWidget *);
    qt_mac_clearCocoaViewQWidgetPointers(this);
#endif

    if (!d->children.isEmpty())
        d->deleteChildren();

    QApplication::removePostedEvents(this);

    QT_TRY {
        destroy();                                        // platform-dependent cleanup
    } QT_CATCH(...) {
        // if this fails we can't do anything about it but at least we are not allowed to throw.
    }
    --QWidgetPrivate::instanceCounter;

    if (QWidgetPrivate::allWidgets) // might have been deleted by ~QApplication
        QWidgetPrivate::allWidgets->remove(this);

    QT_TRY {
        QEvent e(QEvent::Destroy);
        QCoreApplication::sendEvent(this, &e);
    } QT_CATCH(const std::exception&) {
        // if this fails we can't do anything about it but at least we are not allowed to throw.
    }
}

int QWidgetPrivate::instanceCounter = 0;  // Current number of widget instances
int QWidgetPrivate::maxInstances = 0;     // Maximum number of widget instances

void QWidgetPrivate::setWinId(WId id)                // set widget identifier
{
    Q_Q(QWidget);
    // the user might create a widget with Qt::Desktop window
    // attribute (or create another QDesktopWidget instance), which
    // will have the same windowid (the root window id) as the
    // qt_desktopWidget. We should not add the second desktop widget
    // to the mapper.
    bool userDesktopWidget = qt_desktopWidget != 0 && qt_desktopWidget != q && q->windowType() == Qt::Desktop;
    if (mapper && data.winid && !userDesktopWidget) {
        mapper->remove(data.winid);
    }

    const WId oldWinId = data.winid;

    data.winid = id;
#if defined(Q_WS_X11)
    hd = id; // X11: hd == ident
#endif
    if (mapper && id && !userDesktopWidget) {
        mapper->insert(data.winid, q);
    }

    if(oldWinId != id) {
        // Do not emit an event when the old winId is destroyed.  This only
        // happens (a) during widget destruction, and (b) immediately prior
        // to creation of a new winId, for example as a result of re-parenting.
        if(id != 0) {
            QEvent e(QEvent::WinIdChange);
            QCoreApplication::sendEvent(q, &e);
        }
    }
}

void QWidgetPrivate::createTLExtra()
{
    if (!extra)
        createExtra();
    if (!extra->topextra) {
        QTLWExtra* x = extra->topextra = new QTLWExtra;
        x->icon = 0;
        x->iconPixmap = 0;
        x->windowSurface = 0;
        x->sharedPainter = 0;
        x->incw = x->inch = 0;
        x->basew = x->baseh = 0;
        x->frameStrut.setCoords(0, 0, 0, 0);
        x->normalGeometry = QRect(0,0,-1,-1);
        x->savedFlags = 0;
        x->opacity = 255;
        x->posFromMove = false;
        x->sizeAdjusted = false;
        x->inTopLevelResize = false;
        x->inRepaint = false;
        x->embedded = 0;
#ifdef Q_WS_MAC
#ifdef QT_MAC_USE_COCOA
        x->wasMaximized = false;
#endif // QT_MAC_USE_COCOA
#endif // Q_WS_MAC
        createTLSysExtra();
#ifdef QWIDGET_EXTRA_DEBUG
        static int count = 0;
        qDebug() << "tlextra" << ++count;
#endif
#if defined(Q_WS_QPA)
        x->platformWindow = 0;
        x->platformWindowFormat = QPlatformWindowFormat::defaultFormat();
#endif
    }
}

/*!
  \internal
  Creates the widget extra data.
*/

void QWidgetPrivate::createExtra()
{
    if (!extra) {                                // if not exists
        extra = new QWExtra;
        extra->glContext = 0;
        extra->topextra = 0;
#ifndef QT_NO_GRAPHICSVIEW
        extra->proxyWidget = 0;
#endif
#ifndef QT_NO_CURSOR
        extra->curs = 0;
#endif
        extra->minw = 0;
        extra->minh = 0;
        extra->maxw = QWIDGETSIZE_MAX;
        extra->maxh = QWIDGETSIZE_MAX;
        extra->customDpiX = 0;
        extra->customDpiY = 0;
        extra->explicitMinSize = 0;
        extra->explicitMaxSize = 0;
        extra->autoFillBackground = 0;
        extra->nativeChildrenForced = 0;
        extra->inRenderWithPainter = 0;
        extra->hasMask = 0;
        createSysExtra();
#ifdef QWIDGET_EXTRA_DEBUG
        static int count = 0;
        qDebug() << "extra" << ++count;
#endif
    }
}


/*!
  \internal
  Deletes the widget extra data.
*/

void QWidgetPrivate::deleteExtra()
{
    if (extra) {                                // if exists
#ifndef QT_NO_CURSOR
        delete extra->curs;
#endif
        deleteSysExtra();
#ifndef QT_NO_STYLE_STYLESHEET
        // dereference the stylesheet style
        if (QStyleSheetStyle *proxy = qobject_cast<QStyleSheetStyle *>(extra->style))
            proxy->deref();
#endif
        if (extra->topextra) {
            deleteTLSysExtra();
            extra->topextra->backingStore.destroy();
            delete extra->topextra->icon;
            delete extra->topextra->iconPixmap;
#if defined(Q_WS_QWS) && !defined(QT_NO_QWS_MANAGER)
            delete extra->topextra->qwsManager;
#endif
            delete extra->topextra->windowSurface;
            delete extra->topextra;
        }
        delete extra;
        // extra->xic destroyed in QWidget::destroy()
        extra = 0;
    }
}

/*
  Returns true if there are widgets above this which overlap with
  \a rect, which is in parent's coordinate system (same as crect).
*/

bool QWidgetPrivate::isOverlapped(const QRect &rect) const
{
    Q_Q(const QWidget);

    const QWidget *w = q;
    QRect r = rect;
    while (w) {
        if (w->isWindow())
            return false;
        QWidgetPrivate *pd = w->parentWidget()->d_func();
        bool above = false;
        for (int i = 0; i < pd->children.size(); ++i) {
            QWidget *sibling = qobject_cast<QWidget *>(pd->children.at(i));
            if (!sibling || !sibling->isVisible() || sibling->isWindow())
                continue;
            if (!above) {
                above = (sibling == w);
                continue;
            }

            if (qRectIntersects(sibling->d_func()->effectiveRectFor(sibling->data->crect), r)) {
                const QWExtra *siblingExtra = sibling->d_func()->extra;
                if (siblingExtra && siblingExtra->hasMask && !sibling->d_func()->graphicsEffect
                    && !siblingExtra->mask.translated(sibling->data->crect.topLeft()).intersects(r)) {
                    continue;
                }
                return true;
            }
        }
        w = w->parentWidget();
        r.translate(pd->data.crect.topLeft());
    }
    return false;
}

void QWidgetPrivate::syncBackingStore()
{
    if (paintOnScreen()) {
        repaint_sys(dirty);
        dirty = QRegion();
    } else if (QWidgetBackingStore *bs = maybeBackingStore()) {
        bs->sync();
    }
}

void QWidgetPrivate::syncBackingStore(const QRegion &region)
{
    if (paintOnScreen())
        repaint_sys(region);
    else if (QWidgetBackingStore *bs = maybeBackingStore()) {
        bs->sync(q_func(), region);
    }
}

void QWidgetPrivate::setUpdatesEnabled_helper(bool enable)
{
    Q_Q(QWidget);

    if (enable && !q->isWindow() && q->parentWidget() && !q->parentWidget()->updatesEnabled())
        return; // nothing we can do

    if (enable != q->testAttribute(Qt::WA_UpdatesDisabled))
        return; // nothing to do

    q->setAttribute(Qt::WA_UpdatesDisabled, !enable);
    if (enable)
        q->update();

    Qt::WidgetAttribute attribute = enable ? Qt::WA_ForceUpdatesDisabled : Qt::WA_UpdatesDisabled;
    for (int i = 0; i < children.size(); ++i) {
        QWidget *w = qobject_cast<QWidget *>(children.at(i));
        if (w && !w->isWindow() && !w->testAttribute(attribute))
            w->d_func()->setUpdatesEnabled_helper(enable);
    }
}

/*!
    \internal

    Propagate this widget's palette to all children, except style sheet
    widgets, and windows that don't enable window propagation (palettes don't
    normally propagate to windows).
*/
void QWidgetPrivate::propagatePaletteChange()
{
    Q_Q(QWidget);
    // Propagate a new inherited mask to all children.
#ifndef QT_NO_GRAPHICSVIEW
    if (!q->parentWidget() && extra && extra->proxyWidget) {
        QGraphicsProxyWidget *p = extra->proxyWidget;
        inheritedPaletteResolveMask = p->d_func()->inheritedPaletteResolveMask | p->palette().resolve();
    } else
#endif //QT_NO_GRAPHICSVIEW
        if (q->isWindow() && !q->testAttribute(Qt::WA_WindowPropagation)) {
        inheritedPaletteResolveMask = 0;
    }
    int mask = data.pal.resolve() | inheritedPaletteResolveMask;

    QEvent pc(QEvent::PaletteChange);
    QApplication::sendEvent(q, &pc);
    for (int i = 0; i < children.size(); ++i) {
        QWidget *w = qobject_cast<QWidget*>(children.at(i));
        if (w && !w->testAttribute(Qt::WA_StyleSheet)
            && (!w->isWindow() || w->testAttribute(Qt::WA_WindowPropagation))) {
            QWidgetPrivate *wd = w->d_func();
            wd->inheritedPaletteResolveMask = mask;
            wd->resolvePalette();
        }
    }
#if defined(QT3_SUPPORT)
    q->paletteChange(q->palette()); // compatibility
#endif
}

/*
  Returns the widget's clipping rectangle.
*/
QRect QWidgetPrivate::clipRect() const
{
    Q_Q(const QWidget);
    const QWidget * w = q;
    if (!w->isVisible())
        return QRect();
    QRect r = effectiveRectFor(q->rect());
    int ox = 0;
    int oy = 0;
    while (w
            && w->isVisible()
            && !w->isWindow()
            && w->parentWidget()) {
        ox -= w->x();
        oy -= w->y();
        w = w->parentWidget();
        r &= QRect(ox, oy, w->width(), w->height());
    }
    return r;
}

/*
  Returns the widget's clipping region (without siblings).
*/
QRegion QWidgetPrivate::clipRegion() const
{
    Q_Q(const QWidget);
    if (!q->isVisible())
        return QRegion();
    QRegion r(q->rect());
    const QWidget * w = q;
    const QWidget *ignoreUpTo;
    int ox = 0;
    int oy = 0;
    while (w
           && w->isVisible()
           && !w->isWindow()
           && w->parentWidget()) {
        ox -= w->x();
        oy -= w->y();
        ignoreUpTo = w;
        w = w->parentWidget();
        r &= QRegion(ox, oy, w->width(), w->height());

        int i = 0;
        while(w->d_func()->children.at(i++) != static_cast<const QObject *>(ignoreUpTo))
            ;
        for ( ; i < w->d_func()->children.size(); ++i) {
            if(QWidget *sibling = qobject_cast<QWidget *>(w->d_func()->children.at(i))) {
                if(sibling->isVisible() && !sibling->isWindow()) {
                    QRect siblingRect(ox+sibling->x(), oy+sibling->y(),
                                      sibling->width(), sibling->height());
                    if (qRectIntersects(siblingRect, q->rect()))
                        r -= QRegion(siblingRect);
                }
            }
        }
    }
    return r;
}

#ifndef QT_NO_GRAPHICSEFFECT
void QWidgetPrivate::invalidateGraphicsEffectsRecursively()
{
    Q_Q(QWidget);
    QWidget *w = q;
    do {
        if (w->graphicsEffect()) {
            QWidgetEffectSourcePrivate *sourced =
                static_cast<QWidgetEffectSourcePrivate *>(w->graphicsEffect()->source()->d_func());
            if (!sourced->updateDueToGraphicsEffect)
                w->graphicsEffect()->source()->d_func()->invalidateCache();
        }
        w = w->parentWidget();
    } while (w);
}
#endif //QT_NO_GRAPHICSEFFECT

void QWidgetPrivate::setDirtyOpaqueRegion()
{
    Q_Q(QWidget);

    dirtyOpaqueChildren = true;

#ifndef QT_NO_GRAPHICSEFFECT
    invalidateGraphicsEffectsRecursively();
#endif //QT_NO_GRAPHICSEFFECT

    if (q->isWindow())
        return;

    QWidget *parent = q->parentWidget();
    if (!parent)
        return;

    // TODO: instead of setting dirtyflag, manipulate the dirtyregion directly?
    QWidgetPrivate *pd = parent->d_func();
    if (!pd->dirtyOpaqueChildren)
        pd->setDirtyOpaqueRegion();
}

const QRegion &QWidgetPrivate::getOpaqueChildren() const
{
    if (!dirtyOpaqueChildren)
        return opaqueChildren;

    QWidgetPrivate *that = const_cast<QWidgetPrivate*>(this);
    that->opaqueChildren = QRegion();

    for (int i = 0; i < children.size(); ++i) {
        QWidget *child = qobject_cast<QWidget *>(children.at(i));
        if (!child || !child->isVisible() || child->isWindow())
            continue;

        const QPoint offset = child->geometry().topLeft();
        QWidgetPrivate *childd = child->d_func();
        QRegion r = childd->isOpaque ? child->rect() : childd->getOpaqueChildren();
        if (childd->extra && childd->extra->hasMask)
            r &= childd->extra->mask;
        if (r.isEmpty())
            continue;
        r.translate(offset);
        that->opaqueChildren += r;
    }

    that->opaqueChildren &= q_func()->rect();
    that->dirtyOpaqueChildren = false;

    return that->opaqueChildren;
}

void QWidgetPrivate::subtractOpaqueChildren(QRegion &source, const QRect &clipRect) const
{
    if (children.isEmpty() || clipRect.isEmpty())
        return;

    const QRegion &r = getOpaqueChildren();
    if (!r.isEmpty())
        source -= (r & clipRect);
}

//subtract any relatives that are higher up than me --- this is too expensive !!!
void QWidgetPrivate::subtractOpaqueSiblings(QRegion &sourceRegion, bool *hasDirtySiblingsAbove,
                                            bool alsoNonOpaque) const
{
    Q_Q(const QWidget);
    static int disableSubtractOpaqueSiblings = qgetenv("QT_NO_SUBTRACTOPAQUESIBLINGS").toInt();
    if (disableSubtractOpaqueSiblings || q->isWindow())
        return;

    QRect clipBoundingRect;
    bool dirtyClipBoundingRect = true;

    QRegion parentClip;
    bool dirtyParentClip = true;

    QPoint parentOffset = data.crect.topLeft();

    const QWidget *w = q;

    while (w) {
        if (w->isWindow())
            break;
        QWidgetPrivate *pd = w->parentWidget()->d_func();
        const int myIndex = pd->children.indexOf(const_cast<QWidget *>(w));
        const QRect widgetGeometry = w->d_func()->effectiveRectFor(w->data->crect);
        for (int i = myIndex + 1; i < pd->children.size(); ++i) {
            QWidget *sibling = qobject_cast<QWidget *>(pd->children.at(i));
            if (!sibling || !sibling->isVisible() || sibling->isWindow())
                continue;

            const QRect siblingGeometry = sibling->d_func()->effectiveRectFor(sibling->data->crect);
            if (!qRectIntersects(siblingGeometry, widgetGeometry))
                continue;

            if (dirtyClipBoundingRect) {
                clipBoundingRect = sourceRegion.boundingRect();
                dirtyClipBoundingRect = false;
            }

            if (!qRectIntersects(siblingGeometry, clipBoundingRect.translated(parentOffset)))
                continue;

            if (dirtyParentClip) {
                parentClip = sourceRegion.translated(parentOffset);
                dirtyParentClip = false;
            }

            const QPoint siblingPos(sibling->data->crect.topLeft());
            const QRect siblingClipRect(sibling->d_func()->clipRect());
            QRegion siblingDirty(parentClip);
            siblingDirty &= (siblingClipRect.translated(siblingPos));
            const bool hasMask = sibling->d_func()->extra && sibling->d_func()->extra->hasMask
                                 && !sibling->d_func()->graphicsEffect;
            if (hasMask)
                siblingDirty &= sibling->d_func()->extra->mask.translated(siblingPos);
            if (siblingDirty.isEmpty())
                continue;

            if (sibling->d_func()->isOpaque || alsoNonOpaque) {
                if (hasMask) {
                    siblingDirty.translate(-parentOffset);
                    sourceRegion -= siblingDirty;
                } else {
                    sourceRegion -= siblingGeometry.translated(-parentOffset);
                }
            } else {
                if (hasDirtySiblingsAbove)
                    *hasDirtySiblingsAbove = true;
                if (sibling->d_func()->children.isEmpty())
                    continue;
                QRegion opaqueSiblingChildren(sibling->d_func()->getOpaqueChildren());
                opaqueSiblingChildren.translate(-parentOffset + siblingPos);
                sourceRegion -= opaqueSiblingChildren;
            }
            if (sourceRegion.isEmpty())
                return;

            dirtyClipBoundingRect = true;
            dirtyParentClip = true;
        }

        w = w->parentWidget();
        parentOffset += pd->data.crect.topLeft();
        dirtyParentClip = true;
    }
}

void QWidgetPrivate::clipToEffectiveMask(QRegion &region) const
{
    Q_Q(const QWidget);

    const QWidget *w = q;
    QPoint offset;

#ifndef QT_NO_GRAPHICSEFFECT
    if (graphicsEffect) {
        w = q->parentWidget();
        offset -= data.crect.topLeft();
    }
#endif //QT_NO_GRAPHICSEFFECT

    while (w) {
        const QWidgetPrivate *wd = w->d_func();
        if (wd->extra && wd->extra->hasMask)
            region &= (w != q) ? wd->extra->mask.translated(offset) : wd->extra->mask;
        if (w->isWindow())
            return;
        offset -= wd->data.crect.topLeft();
        w = w->parentWidget();
    }
}

bool QWidgetPrivate::paintOnScreen() const
{
#if defined(Q_WS_QWS)
    return false;
#elif  defined(QT_NO_BACKINGSTORE)
    return true;
#else
    Q_Q(const QWidget);
    if (q->testAttribute(Qt::WA_PaintOnScreen)
            || (!q->isWindow() && q->window()->testAttribute(Qt::WA_PaintOnScreen))) {
        return true;
    }

    return !qt_enable_backingstore;
#endif
}

void QWidgetPrivate::updateIsOpaque()
{
    // hw: todo: only needed if opacity actually changed
    setDirtyOpaqueRegion();

#ifndef QT_NO_GRAPHICSEFFECT
    if (graphicsEffect) {
        // ### We should probably add QGraphicsEffect::isOpaque at some point.
        setOpaque(false);
        return;
    }
#endif //QT_NO_GRAPHICSEFFECT

    Q_Q(QWidget);
#ifdef Q_WS_X11
    if (q->testAttribute(Qt::WA_X11OpenGLOverlay)) {
        setOpaque(false);
        return;
    }
#endif

#ifdef Q_WS_S60
    if (q->windowType() == Qt::Dialog && q->testAttribute(Qt::WA_TranslucentBackground)
                && S60->avkonComponentsSupportTransparency) {
        setOpaque(false);
        return;
    }
#endif

    if (q->testAttribute(Qt::WA_OpaquePaintEvent) || q->testAttribute(Qt::WA_PaintOnScreen)) {
        setOpaque(true);
        return;
    }

    const QPalette &pal = q->palette();

    if (q->autoFillBackground()) {
        const QBrush &autoFillBrush = pal.brush(q->backgroundRole());
        if (autoFillBrush.style() != Qt::NoBrush && autoFillBrush.isOpaque()) {
            setOpaque(true);
            return;
        }
    }

    if (q->isWindow() && !q->testAttribute(Qt::WA_NoSystemBackground)) {
        const QBrush &windowBrush = q->palette().brush(QPalette::Window);
        if (windowBrush.style() != Qt::NoBrush && windowBrush.isOpaque()) {
            setOpaque(true);
            return;
        }
    }
    setOpaque(false);
}

void QWidgetPrivate::setOpaque(bool opaque)
{
    if (isOpaque == opaque)
        return;
    isOpaque = opaque;
#ifdef Q_WS_MAC
    macUpdateIsOpaque();
#endif
#ifdef Q_WS_X11
    x11UpdateIsOpaque();
#endif
#ifdef Q_WS_WIN
    winUpdateIsOpaque();
#endif
#ifdef Q_OS_SYMBIAN
    s60UpdateIsOpaque();
#endif
}

void QWidgetPrivate::updateIsTranslucent()
{
#ifdef Q_WS_MAC
    macUpdateIsOpaque();
#endif
#ifdef Q_WS_X11
    x11UpdateIsOpaque();
#endif
#ifdef Q_WS_WIN
    winUpdateIsOpaque();
#endif
#ifdef Q_OS_SYMBIAN
    s60UpdateIsOpaque();
#endif
}

/*!
    \fn void QPixmap::fill(const QWidget *widget, const QPoint &offset)

    Fills the pixmap with the \a widget's background color or pixmap
    according to the given offset.

    The QPoint \a offset defines a point in widget coordinates to
    which the pixmap's top-left pixel will be mapped to. This is only
    significant if the widget has a background pixmap; otherwise the
    pixmap will simply be filled with the background color of the
    widget.
*/

void QPixmap::fill( const QWidget *widget, const QPoint &off )
{
    QPainter p(this);
    p.translate(-off);
    widget->d_func()->paintBackground(&p, QRect(off, size()));
}

static inline void fillRegion(QPainter *painter, const QRegion &rgn, const QBrush &brush)
{
    Q_ASSERT(painter);

    if (brush.style() == Qt::TexturePattern) {
#ifdef Q_WS_MAC
        // Optimize pattern filling on mac by using HITheme directly
        // when filling with the standard widget background.
        // Defined in qmacstyle_mac.cpp
        extern void qt_mac_fill_background(QPainter *painter, const QRegion &rgn, const QBrush &brush);
        qt_mac_fill_background(painter, rgn, brush);
#else
#if !defined(QT_NO_STYLE_S60)
        // Defined in qs60style.cpp
        extern bool qt_s60_fill_background(QPainter *painter, const QRegion &rgn, const QBrush &brush);
        if (!qt_s60_fill_background(painter, rgn, brush))
#endif // !defined(QT_NO_STYLE_S60)
        {
            const QRect rect(rgn.boundingRect());
            painter->setClipRegion(rgn);
            painter->drawTiledPixmap(rect, brush.texture(), rect.topLeft());
        }
#endif // Q_WS_MAC

    } else if (brush.gradient()
               && brush.gradient()->coordinateMode() == QGradient::ObjectBoundingMode) {
        painter->save();
        painter->setClipRegion(rgn);
        painter->fillRect(0, 0, painter->device()->width(), painter->device()->height(), brush);
        painter->restore();
    } else {
        const QVector<QRect> &rects = rgn.rects();
        for (int i = 0; i < rects.size(); ++i)
            painter->fillRect(rects.at(i), brush);
    }
}

void QWidgetPrivate::paintBackground(QPainter *painter, const QRegion &rgn, int flags) const
{
    Q_Q(const QWidget);

#ifndef QT_NO_SCROLLAREA
    bool resetBrushOrigin = false;
    QPointF oldBrushOrigin;
    //If we are painting the viewport of a scrollarea, we must apply an offset to the brush in case we are drawing a texture
    QAbstractScrollArea *scrollArea = qobject_cast<QAbstractScrollArea *>(parent);
    if (scrollArea && scrollArea->viewport() == q) {
        QObjectData *scrollPrivate = static_cast<QWidget *>(scrollArea)->d_ptr.data();
        QAbstractScrollAreaPrivate *priv = static_cast<QAbstractScrollAreaPrivate *>(scrollPrivate);
        oldBrushOrigin = painter->brushOrigin();
        resetBrushOrigin = true;
        painter->setBrushOrigin(-priv->contentsOffset());

    }
#endif // QT_NO_SCROLLAREA

    const QBrush autoFillBrush = q->palette().brush(q->backgroundRole());

    if ((flags & DrawAsRoot) && !(q->autoFillBackground() && autoFillBrush.isOpaque())) {
        const QBrush bg = q->palette().brush(QPalette::Window);
#ifdef Q_WS_QWS
        if (!(flags & DontSetCompositionMode) && painter->paintEngine()->hasFeature(QPaintEngine::PorterDuff))
            painter->setCompositionMode(QPainter::CompositionMode_Source); //copy alpha straight in
#endif
        fillRegion(painter, rgn, bg);
    }

    if (q->autoFillBackground())
        fillRegion(painter, rgn, autoFillBrush);

    if (q->testAttribute(Qt::WA_StyledBackground)) {
        painter->setClipRegion(rgn);
        QStyleOption opt;
        opt.initFrom(q);
        q->style()->drawPrimitive(QStyle::PE_Widget, &opt, painter, q);
    }

#ifndef QT_NO_SCROLLAREA
    if (resetBrushOrigin)
        painter->setBrushOrigin(oldBrushOrigin);
#endif // QT_NO_SCROLLAREA
}

/*
  \internal
  This function is called when a widget is hidden or destroyed.
  It resets some application global pointers that should only refer active,
  visible widgets.
*/

#ifdef Q_WS_MAC
    extern QPointer<QWidget> qt_button_down;
#else
    extern QWidget *qt_button_down;
#endif

void QWidgetPrivate::deactivateWidgetCleanup()
{
    Q_Q(QWidget);
    // If this was the active application window, reset it
    if (QApplication::activeWindow() == q)
        QApplication::setActiveWindow(0);
    // If the is the active mouse press widget, reset it
    if (q == qt_button_down)
        qt_button_down = 0;
}


/*!
    Returns a pointer to the widget with window identifer/handle \a
    id.

    The window identifier type depends on the underlying window
    system, see \c qwindowdefs.h for the actual definition. If there
    is no widget with this identifier, 0 is returned.
*/

QWidget *QWidget::find(WId id)
{
    return QWidgetPrivate::mapper ? QWidgetPrivate::mapper->value(id, 0) : 0;
}



/*!
    \fn WId QWidget::internalWinId() const
    \internal
    Returns the window system identifier of the widget, or 0 if the widget is not created yet.

*/

/*!
    \fn WId QWidget::winId() const

    Returns the window system identifier of the widget.

    Portable in principle, but if you use it you are probably about to
    do something non-portable. Be careful.

    If a widget is non-native (alien) and winId() is invoked on it, that widget
    will be provided a native handle.

    On Mac OS X, the type returned depends on which framework Qt was linked
    against. If Qt is using Carbon, the {WId} is actually an HIViewRef. If Qt
    is using Cocoa, {WId} is a pointer to an NSView.

    This value may change at run-time. An event with type QEvent::WinIdChange
    will be sent to the widget following a change in window system identifier.

    \sa find()
*/
WId QWidget::winId() const
{
    if (!testAttribute(Qt::WA_WState_Created) || !internalWinId()) {
#ifdef ALIEN_DEBUG
        qDebug() << "QWidget::winId: creating native window for" << this;
#endif
        QWidget *that = const_cast<QWidget*>(this);
#ifndef Q_WS_QPA
        that->setAttribute(Qt::WA_NativeWindow);
#endif
        that->d_func()->createWinId();
        return that->data->winid;
    }
    return data->winid;
}


void QWidgetPrivate::createWinId(WId winid)
{
    Q_Q(QWidget);

#ifdef ALIEN_DEBUG
    qDebug() << "QWidgetPrivate::createWinId for" << q << winid;
#endif
    const bool forceNativeWindow = q->testAttribute(Qt::WA_NativeWindow);
    if (!q->testAttribute(Qt::WA_WState_Created) || (forceNativeWindow && !q->internalWinId())) {
#ifndef Q_WS_QPA
        if (!q->isWindow()) {
            QWidget *parent = q->parentWidget();
            QWidgetPrivate *pd = parent->d_func();
            if (forceNativeWindow && !q->testAttribute(Qt::WA_DontCreateNativeAncestors))
                parent->setAttribute(Qt::WA_NativeWindow);
            if (!parent->internalWinId()) {
                pd->createWinId();
            }

            for (int i = 0; i < pd->children.size(); ++i) {
                QWidget *w = qobject_cast<QWidget *>(pd->children.at(i));
                if (w && !w->isWindow() && (!w->testAttribute(Qt::WA_WState_Created)
                                            || (!w->internalWinId() && w->testAttribute(Qt::WA_NativeWindow)))) {
                    if (w!=q) {
                        w->create();
                    } else {
                        w->create(winid);
                        // if the window has already been created, we
                        // need to raise it to its proper stacking position
                        if (winid)
                            w->raise();
                    }
                }
            }
        } else {
            q->create();
        }
#else
        Q_UNUSED(winid);
        q->create();
#endif //Q_WS_QPA

    }
}


/*!
\internal
Ensures that the widget has a window system identifier, i.e. that it is known to the windowing system.

*/

void QWidget::createWinId()
{
    Q_D(QWidget);
#ifdef ALIEN_DEBUG
    qDebug()  << "QWidget::createWinId" << this;
#endif
//    qWarning("QWidget::createWinId is obsolete, please fix your code.");
    d->createWinId();
}

/*!
    \since 4.4

    Returns the effective window system identifier of the widget, i.e. the
    native parent's window system identifier.

    If the widget is native, this function returns the native widget ID.
    Otherwise, the window ID of the first native parent widget, i.e., the
    top-level widget that contains this widget, is returned.

    \note We recommend that you do not store this value as it is likely to
    change at run-time.

    \sa nativeParentWidget()
*/
WId QWidget::effectiveWinId() const
{
    WId id = internalWinId();
    if (id || !testAttribute(Qt::WA_WState_Created))
        return id;
    QWidget *realParent = nativeParentWidget();
    Q_ASSERT(realParent);
    Q_ASSERT(realParent->internalWinId());
    return realParent->internalWinId();
}

#ifndef QT_NO_STYLE_STYLESHEET

/*!
    \property QWidget::styleSheet
    \brief the widget's style sheet
    \since 4.2

    The style sheet contains a textual description of customizations to the
    widget's style, as described in the \l{Qt Style Sheets} document.

    Since Qt 4.5, Qt style sheets fully supports Mac OS X.

    \warning Qt style sheets are currently not supported for custom QStyle
    subclasses. We plan to address this in some future release.

    \sa setStyle(), QApplication::styleSheet, {Qt Style Sheets}
*/
QString QWidget::styleSheet() const
{
    Q_D(const QWidget);
    if (!d->extra)
        return QString();
    return d->extra->styleSheet;
}

void QWidget::setStyleSheet(const QString& styleSheet)
{
    Q_D(QWidget);
    d->createExtra();

    QStyleSheetStyle *proxy = qobject_cast<QStyleSheetStyle *>(d->extra->style);
    d->extra->styleSheet = styleSheet;
    if (styleSheet.isEmpty()) { // stylesheet removed
        if (!proxy)
            return;

        d->inheritStyle();
        return;
    }

    if (proxy) { // style sheet update
        proxy->repolish(this);
        return;
    }

    if (testAttribute(Qt::WA_SetStyle)) {
        d->setStyle_helper(new QStyleSheetStyle(d->extra->style), true);
    } else {
        d->setStyle_helper(new QStyleSheetStyle(0), true);
    }
}

#endif // QT_NO_STYLE_STYLESHEET

/*!
    \sa QWidget::setStyle(), QApplication::setStyle(), QApplication::style()
*/

QStyle *QWidget::style() const
{
    Q_D(const QWidget);

    if (d->extra && d->extra->style)
        return d->extra->style;
    return QApplication::style();
}

/*!
    Sets the widget's GUI style to \a style. The ownership of the style
    object is not transferred.

    If no style is set, the widget uses the application's style,
    QApplication::style() instead.

    Setting a widget's style has no effect on existing or future child
    widgets.

    \warning This function is particularly useful for demonstration
    purposes, where you want to show Qt's styling capabilities. Real
    applications should avoid it and use one consistent GUI style
    instead.

    \warning Qt style sheets are currently not supported for custom QStyle
    subclasses. We plan to address this in some future release.

    \sa style(), QStyle, QApplication::style(), QApplication::setStyle()
*/

void QWidget::setStyle(QStyle *style)
{
    Q_D(QWidget);
    setAttribute(Qt::WA_SetStyle, style != 0);
    d->createExtra();
#ifndef QT_NO_STYLE_STYLESHEET
    if (QStyleSheetStyle *proxy = qobject_cast<QStyleSheetStyle *>(style)) {
        //if for some reason someone try to set a QStyleSheetStyle, ref it
        //(this may happen for exemple in QButtonDialogBox which propagates its style)
        proxy->ref();
        d->setStyle_helper(style, false);
    } else if (qobject_cast<QStyleSheetStyle *>(d->extra->style) || !qApp->styleSheet().isEmpty()) {
        // if we have an application stylesheet or have a proxy already, propagate
        d->setStyle_helper(new QStyleSheetStyle(style), true);
    } else
#endif
        d->setStyle_helper(style, false);
}

void QWidgetPrivate::setStyle_helper(QStyle *newStyle, bool propagate, bool
#ifdef Q_WS_MAC
        metalHack
#endif
        )
{
    Q_Q(QWidget);
    QStyle *oldStyle  = q->style();
#ifndef QT_NO_STYLE_STYLESHEET
    QWeakPointer<QStyle> origStyle;
#endif

#ifdef Q_WS_MAC
    // the metalhack boolean allows Qt/Mac to do a proper re-polish depending
    // on how the Qt::WA_MacBrushedMetal attribute is set. It is only ever
    // set when changing that attribute and passes the widget's CURRENT style.
    // therefore no need to do a reassignment.
    if (!metalHack)
#endif
    {
        createExtra();

#ifndef QT_NO_STYLE_STYLESHEET
        origStyle = extra->style.data();
#endif
        extra->style = newStyle;
    }

    // repolish
    if (q->windowType() != Qt::Desktop) {
        if (polished) {
            oldStyle->unpolish(q);
#ifdef Q_WS_MAC
            if (metalHack)
                macUpdateMetalAttribute();
#endif
            q->style()->polish(q);
#ifdef Q_WS_MAC
        } else if (metalHack) {
            macUpdateMetalAttribute();
#endif
        }
    }

    if (propagate) {
        for (int i = 0; i < children.size(); ++i) {
            QWidget *c = qobject_cast<QWidget*>(children.at(i));
            if (c)
                c->d_func()->inheritStyle();
        }
    }

#ifndef QT_NO_STYLE_STYLESHEET
    if (!qobject_cast<QStyleSheetStyle*>(newStyle)) {
        if (const QStyleSheetStyle* cssStyle = qobject_cast<QStyleSheetStyle*>(origStyle.data())) {
            cssStyle->clearWidgetFont(q);
        }
    }
#endif

    QEvent e(QEvent::StyleChange);
    QApplication::sendEvent(q, &e);
#ifdef QT3_SUPPORT
    q->styleChange(*oldStyle);
#endif

#ifndef QT_NO_STYLE_STYLESHEET
    // dereference the old stylesheet style
    if (QStyleSheetStyle *proxy = qobject_cast<QStyleSheetStyle *>(origStyle.data()))
        proxy->deref();
#endif
}

// Inherits style from the current parent and propagates it as necessary
void QWidgetPrivate::inheritStyle()
{
#ifndef QT_NO_STYLE_STYLESHEET
    Q_Q(QWidget);

    QStyleSheetStyle *proxy = extra ? qobject_cast<QStyleSheetStyle *>(extra->style) : 0;

    if (!q->styleSheet().isEmpty()) {
        Q_ASSERT(proxy);
        proxy->repolish(q);
        return;
    }

    QStyle *origStyle = proxy ? proxy->base : (extra ? (QStyle*)extra->style : 0);
    QWidget *parent = q->parentWidget();
    QStyle *parentStyle = (parent && parent->d_func()->extra) ? (QStyle*)parent->d_func()->extra->style : 0;
    // If we have stylesheet on app or parent has stylesheet style, we need
    // to be running a proxy
    if (!qApp->styleSheet().isEmpty() || qobject_cast<QStyleSheetStyle *>(parentStyle)) {
        QStyle *newStyle = parentStyle;
        if (q->testAttribute(Qt::WA_SetStyle))
            newStyle = new QStyleSheetStyle(origStyle);
        else if (QStyleSheetStyle *newProxy = qobject_cast<QStyleSheetStyle *>(parentStyle))
            newProxy->ref();

        setStyle_helper(newStyle, true);
        return;
    }

    // So, we have no stylesheet on parent/app and we have an empty stylesheet
    // we just need our original style back
    if (origStyle == (extra ? (QStyle*)extra->style : 0)) // is it any different?
        return;

    // We could have inherited the proxy from our parent (which has a custom style)
    // In such a case we need to start following the application style (i.e revert
    // the propagation behavior of QStyleSheetStyle)
    if (!q->testAttribute(Qt::WA_SetStyle))
        origStyle = 0;

    setStyle_helper(origStyle, true);
#endif // QT_NO_STYLE_STYLESHEET
}

#ifdef QT3_SUPPORT
/*!
    \overload

    Sets the widget's GUI style to \a style using the QStyleFactory.
*/
QStyle* QWidget::setStyle(const QString &style)
{
    QStyle *s = QStyleFactory::create(style);
    setStyle(s);
    return s;
}
#endif

/*!
    \fn bool QWidget::isWindow() const

    Returns true if the widget is an independent window, otherwise
    returns false.

    A window is a widget that isn't visually the child of any other
    widget and that usually has a frame and a
    \l{QWidget::setWindowTitle()}{window title}.

    A window can have a \l{QWidget::parentWidget()}{parent widget}.
    It will then be grouped with its parent and deleted when the
    parent is deleted, minimized when the parent is minimized etc. If
    supported by the window manager, it will also have a common
    taskbar entry with its parent.

    QDialog and QMainWindow widgets are by default windows, even if a
    parent widget is specified in the constructor. This behavior is
    specified by the Qt::Window flag.

    \sa window(), isModal(), parentWidget()
*/

/*!
    \property QWidget::modal
    \brief whether the widget is a modal widget

    This property only makes sense for windows. A modal widget
    prevents widgets in all other windows from getting any input.

    By default, this property is false.

    \sa isWindow(), windowModality, QDialog
*/

/*!
    \property QWidget::windowModality
    \brief which windows are blocked by the modal widget
    \since 4.1

    This property only makes sense for windows. A modal widget
    prevents widgets in other windows from getting input. The value of
    this property controls which windows are blocked when the widget
    is visible. Changing this property while the window is visible has
    no effect; you must hide() the widget first, then show() it again.

    By default, this property is Qt::NonModal.

    \sa isWindow(), QWidget::modal, QDialog
*/

Qt::WindowModality QWidget::windowModality() const
{
    return static_cast<Qt::WindowModality>(data->window_modality);
}

void QWidget::setWindowModality(Qt::WindowModality windowModality)
{
    data->window_modality = windowModality;
    // setModal_sys() will be called by setAttribute()
    setAttribute(Qt::WA_ShowModal, (data->window_modality != Qt::NonModal));
    setAttribute(Qt::WA_SetWindowModality, true);
}

/*!
    \fn bool QWidget::underMouse() const

    Returns true if the widget is under the mouse cursor; otherwise
    returns false.

    This value is not updated properly during drag and drop
    operations.

    \sa enterEvent(), leaveEvent()
*/

/*!
    \property QWidget::minimized
    \brief whether this widget is minimized (iconified)

    This property is only relevant for windows.

    By default, this property is false.

    \sa showMinimized(), visible, show(), hide(), showNormal(), maximized
*/
bool QWidget::isMinimized() const
{ return data->window_state & Qt::WindowMinimized; }

/*!
    Shows the widget minimized, as an icon.

    Calling this function only affects \l{isWindow()}{windows}.

    \sa showNormal(), showMaximized(), show(), hide(), isVisible(),
        isMinimized()
*/
void QWidget::showMinimized()
{
    bool isMin = isMinimized();
    if (isMin && isVisible())
        return;

    ensurePolished();
#ifdef QT3_SUPPORT
    if (parent())
        QApplication::sendPostedEvents(parent(), QEvent::ChildInserted);
#endif

    if (!isMin)
        setWindowState((windowState() & ~Qt::WindowActive) | Qt::WindowMinimized);
    show();
}

/*!
    \property QWidget::maximized
    \brief whether this widget is maximized

    This property is only relevant for windows.

    \note Due to limitations on some window systems, this does not always
    report the expected results (e.g., if the user on X11 maximizes the
    window via the window manager, Qt has no way of distinguishing this
    from any other resize). This is expected to improve as window manager
    protocols evolve.

    By default, this property is false.

    \sa windowState(), showMaximized(), visible, show(), hide(), showNormal(), minimized
*/
bool QWidget::isMaximized() const
{ return data->window_state & Qt::WindowMaximized; }



/*!
    Returns the current window state. The window state is a OR'ed
    combination of Qt::WindowState: Qt::WindowMinimized,
    Qt::WindowMaximized, Qt::WindowFullScreen, and Qt::WindowActive.

  \sa Qt::WindowState setWindowState()
 */
Qt::WindowStates QWidget::windowState() const
{
    return Qt::WindowStates(data->window_state);
}

/*!\internal

   The function sets the window state on child widgets similar to
   setWindowState(). The difference is that the window state changed
   event has the isOverride() flag set. It exists mainly to keep
   Q3Workspace working.
 */
void QWidget::overrideWindowState(Qt::WindowStates newstate)
{
    QWindowStateChangeEvent e(Qt::WindowStates(data->window_state), true);
    data->window_state  = newstate;
    QApplication::sendEvent(this, &e);
}

/*!
    \fn void QWidget::setWindowState(Qt::WindowStates windowState)

    Sets the window state to \a windowState. The window state is a OR'ed
    combination of Qt::WindowState: Qt::WindowMinimized,
    Qt::WindowMaximized, Qt::WindowFullScreen, and Qt::WindowActive.

    If the window is not visible (i.e. isVisible() returns false), the
    window state will take effect when show() is called. For visible
    windows, the change is immediate. For example, to toggle between
    full-screen and normal mode, use the following code:

    \snippet doc/src/snippets/code/src_gui_kernel_qwidget.cpp 0

    In order to restore and activate a minimized window (while
    preserving its maximized and/or full-screen state), use the following:

    \snippet doc/src/snippets/code/src_gui_kernel_qwidget.cpp 1

    Calling this function will hide the widget. You must call show() to make
    the widget visible again.

    \note On some window systems Qt::WindowActive is not immediate, and may be
    ignored in certain cases.

    When the window state changes, the widget receives a changeEvent()
    of type QEvent::WindowStateChange.

    \sa Qt::WindowState windowState()
*/

/*!
    \property QWidget::fullScreen
    \brief whether the widget is shown in full screen mode

    A widget in full screen mode occupies the whole screen area and does not
    display window decorations, such as a title bar.

    By default, this property is false.

    \sa windowState(), minimized, maximized
*/
bool QWidget::isFullScreen() const
{ return data->window_state & Qt::WindowFullScreen; }

/*!
    Shows the widget in full-screen mode.

    Calling this function only affects \l{isWindow()}{windows}.

    To return from full-screen mode, call showNormal().

    Full-screen mode works fine under Windows, but has certain
    problems under X. These problems are due to limitations of the
    ICCCM protocol that specifies the communication between X11
    clients and the window manager. ICCCM simply does not understand
    the concept of non-decorated full-screen windows. Therefore, the
    best we can do is to request a borderless window and place and
    resize it to fill the entire screen. Depending on the window
    manager, this may or may not work. The borderless window is
    requested using MOTIF hints, which are at least partially
    supported by virtually all modern window managers.

    An alternative would be to bypass the window manager entirely and
    create a window with the Qt::X11BypassWindowManagerHint flag. This
    has other severe problems though, like totally broken keyboard focus
    and very strange effects on desktop changes or when the user raises
    other windows.

    X11 window managers that follow modern post-ICCCM specifications
    support full-screen mode properly.

    \sa showNormal(), showMaximized(), show(), hide(), isVisible()
*/
void QWidget::showFullScreen()
{
#ifdef Q_WS_MAC
    // If the unified toolbar is enabled, we have to disable it before going fullscreen.
    QMainWindow *mainWindow = qobject_cast<QMainWindow*>(this);
    if (mainWindow && mainWindow->unifiedTitleAndToolBarOnMac()) {
        mainWindow->setUnifiedTitleAndToolBarOnMac(false);
        QMainWindowLayout *mainLayout = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
        mainLayout->activateUnifiedToolbarAfterFullScreen = true;
    }
#endif // Q_WS_MAC
    ensurePolished();
#ifdef QT3_SUPPORT
    if (parent())
        QApplication::sendPostedEvents(parent(), QEvent::ChildInserted);
#endif

    setWindowState((windowState() & ~(Qt::WindowMinimized | Qt::WindowMaximized))
                   | Qt::WindowFullScreen);
    show();
    activateWindow();
}

/*!
    Shows the widget maximized.

    Calling this function only affects \l{isWindow()}{windows}.

    On X11, this function may not work properly with certain window
    managers. See the \l{Window Geometry} documentation for an explanation.

    \sa setWindowState(), showNormal(), showMinimized(), show(), hide(), isVisible()
*/
void QWidget::showMaximized()
{
    ensurePolished();
#ifdef QT3_SUPPORT
    if (parent())
        QApplication::sendPostedEvents(parent(), QEvent::ChildInserted);
#endif

    setWindowState((windowState() & ~(Qt::WindowMinimized | Qt::WindowFullScreen))
                   | Qt::WindowMaximized);
#ifdef Q_WS_MAC
    // If the unified toolbar was enabled before going fullscreen, we have to enable it back.
    QMainWindow *mainWindow = qobject_cast<QMainWindow*>(this);
    if (mainWindow)
    {
        QMainWindowLayout *mainLayout = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
        if (mainLayout->activateUnifiedToolbarAfterFullScreen) {
            mainWindow->setUnifiedTitleAndToolBarOnMac(true);
            mainLayout->activateUnifiedToolbarAfterFullScreen = false;
        }
    }
#endif // Q_WS_MAC
    show();
}

/*!
    Restores the widget after it has been maximized or minimized.

    Calling this function only affects \l{isWindow()}{windows}.

    \sa setWindowState(), showMinimized(), showMaximized(), show(), hide(), isVisible()
*/
void QWidget::showNormal()
{
    ensurePolished();
#ifdef QT3_SUPPORT
    if (parent())
        QApplication::sendPostedEvents(parent(), QEvent::ChildInserted);
#endif

    setWindowState(windowState() & ~(Qt::WindowMinimized
                                     | Qt::WindowMaximized
                                     | Qt::WindowFullScreen));
#ifdef Q_WS_MAC
    // If the unified toolbar was enabled before going fullscreen, we have to enable it back.
    QMainWindow *mainWindow = qobject_cast<QMainWindow*>(this);
    if (mainWindow)
    {
        QMainWindowLayout *mainLayout = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
        if (mainLayout->activateUnifiedToolbarAfterFullScreen) {
            mainWindow->setUnifiedTitleAndToolBarOnMac(true);
            mainLayout->activateUnifiedToolbarAfterFullScreen = false;
        }
    }
#endif // Q_WS_MAC
    show();
}

/*!
    Returns true if this widget would become enabled if \a ancestor is
    enabled; otherwise returns false.



    This is the case if neither the widget itself nor every parent up
    to but excluding \a ancestor has been explicitly disabled.

    isEnabledTo(0) is equivalent to isEnabled().

    \sa setEnabled() enabled
*/

bool QWidget::isEnabledTo(QWidget* ancestor) const
{
    const QWidget * w = this;
    while (!w->testAttribute(Qt::WA_ForceDisabled)
            && !w->isWindow()
            && w->parentWidget()
            && w->parentWidget() != ancestor)
        w = w->parentWidget();
    return !w->testAttribute(Qt::WA_ForceDisabled);
}

#ifndef QT_NO_ACTION
/*!
    Appends the action \a action to this widget's list of actions.

    All QWidgets have a list of \l{QAction}s, however they can be
    represented graphically in many different ways. The default use of
    the QAction list (as returned by actions()) is to create a context
    QMenu.

    A QWidget should only have one of each action and adding an action
    it already has will not cause the same action to be in the widget twice.

    The ownership of \a action is not transferred to this QWidget.

    \sa removeAction(), insertAction(), actions(), QMenu
*/
void QWidget::addAction(QAction *action)
{
    insertAction(0, action);
}

/*!
    Appends the actions \a actions to this widget's list of actions.

    \sa removeAction(), QMenu, addAction()
*/
void QWidget::addActions(QList<QAction*> actions)
{
    for(int i = 0; i < actions.count(); i++)
        insertAction(0, actions.at(i));
}

/*!
    Inserts the action \a action to this widget's list of actions,
    before the action \a before. It appends the action if \a before is 0 or
    \a before is not a valid action for this widget.

    A QWidget should only have one of each action.

    \sa removeAction(), addAction(), QMenu, contextMenuPolicy, actions()
*/
void QWidget::insertAction(QAction *before, QAction *action)
{
    if(!action) {
        qWarning("QWidget::insertAction: Attempt to insert null action");
        return;
    }

    Q_D(QWidget);
    if(d->actions.contains(action))
        removeAction(action);

    int pos = d->actions.indexOf(before);
    if (pos < 0) {
        before = 0;
        pos = d->actions.size();
    }
    d->actions.insert(pos, action);

    QActionPrivate *apriv = action->d_func();
    apriv->widgets.append(this);

    QActionEvent e(QEvent::ActionAdded, action, before);
    QApplication::sendEvent(this, &e);
}

/*!
    Inserts the actions \a actions to this widget's list of actions,
    before the action \a before. It appends the action if \a before is 0 or
    \a before is not a valid action for this widget.

    A QWidget can have at most one of each action.

    \sa removeAction(), QMenu, insertAction(), contextMenuPolicy
*/
void QWidget::insertActions(QAction *before, QList<QAction*> actions)
{
    for(int i = 0; i < actions.count(); ++i)
        insertAction(before, actions.at(i));
}

/*!
    Removes the action \a action from this widget's list of actions.
    \sa insertAction(), actions(), insertAction()
*/
void QWidget::removeAction(QAction *action)
{
    if (!action)
        return;

    Q_D(QWidget);

    QActionPrivate *apriv = action->d_func();
    apriv->widgets.removeAll(this);

    if (d->actions.removeAll(action)) {
        QActionEvent e(QEvent::ActionRemoved, action);
        QApplication::sendEvent(this, &e);
    }
}

/*!
    Returns the (possibly empty) list of this widget's actions.

    \sa contextMenuPolicy, insertAction(), removeAction()
*/
QList<QAction*> QWidget::actions() const
{
    Q_D(const QWidget);
    return d->actions;
}
#endif // QT_NO_ACTION

/*!
  \fn bool QWidget::isEnabledToTLW() const
  \obsolete

  This function is deprecated. It is equivalent to isEnabled()
*/

/*!
    \property QWidget::enabled
    \brief whether the widget is enabled

    An enabled widget handles keyboard and mouse events; a disabled
    widget does not.

    Some widgets display themselves differently when they are
    disabled. For example a button might draw its label grayed out. If
    your widget needs to know when it becomes enabled or disabled, you
    can use the changeEvent() with type QEvent::EnabledChange.

    Disabling a widget implicitly disables all its children. Enabling
    respectively enables all child widgets unless they have been
    explicitly disabled.

    By default, this property is true.

    \sa isEnabledTo(), QKeyEvent, QMouseEvent, changeEvent()
*/
void QWidget::setEnabled(bool enable)
{
    Q_D(QWidget);
    setAttribute(Qt::WA_ForceDisabled, !enable);
    d->setEnabled_helper(enable);
}

void QWidgetPrivate::setEnabled_helper(bool enable)
{
    Q_Q(QWidget);

    if (enable && !q->isWindow() && q->parentWidget() && !q->parentWidget()->isEnabled())
        return; // nothing we can do

    if (enable != q->testAttribute(Qt::WA_Disabled))
        return; // nothing to do

    q->setAttribute(Qt::WA_Disabled, !enable);
    updateSystemBackground();

    if (!enable && q->window()->focusWidget() == q) {
        bool parentIsEnabled = (!q->parentWidget() || q->parentWidget()->isEnabled());
        if (!parentIsEnabled || !q->focusNextChild())
            q->clearFocus();
    }

    Qt::WidgetAttribute attribute = enable ? Qt::WA_ForceDisabled : Qt::WA_Disabled;
    for (int i = 0; i < children.size(); ++i) {
        QWidget *w = qobject_cast<QWidget *>(children.at(i));
        if (w && !w->testAttribute(attribute))
            w->d_func()->setEnabled_helper(enable);
    }
#if defined(Q_WS_X11)
    if (q->testAttribute(Qt::WA_SetCursor) || q->isWindow()) {
        // enforce the windows behavior of clearing the cursor on
        // disabled widgets
        qt_x11_enforce_cursor(q);
    }
#endif
#if defined(Q_WS_MAC)
    setEnabled_helper_sys(enable);
#endif
#ifndef QT_NO_IM
    if (q->testAttribute(Qt::WA_InputMethodEnabled) && q->hasFocus()) {
        QWidget *focusWidget = effectiveFocusWidget();
        QInputContext *qic = focusWidget->d_func()->inputContext();
        if (enable) {
            if (focusWidget->testAttribute(Qt::WA_InputMethodEnabled))
                qic->setFocusWidget(focusWidget);
        } else {
            qic->reset();
            qic->setFocusWidget(0);
        }
    }
#endif //QT_NO_IM
    QEvent e(QEvent::EnabledChange);
    QApplication::sendEvent(q, &e);
#ifdef QT3_SUPPORT
    q->enabledChange(!enable); // compatibility
#endif
}

/*!
    \property QWidget::acceptDrops
    \brief whether drop events are enabled for this widget

    Setting this property to true announces to the system that this
    widget \e may be able to accept drop events.

    If the widget is the desktop (windowType() == Qt::Desktop), this may
    fail if another application is using the desktop; you can call
    acceptDrops() to test if this occurs.

    \warning Do not modify this property in a drag and drop event handler.

    By default, this property is false.

    \sa {Drag and Drop}
*/
bool QWidget::acceptDrops() const
{
    return testAttribute(Qt::WA_AcceptDrops);
}

void QWidget::setAcceptDrops(bool on)
{
    setAttribute(Qt::WA_AcceptDrops, on);

}

/*!
    \fn void QWidget::enabledChange(bool)

    \internal
    \obsolete
*/

/*!
    \fn void QWidget::paletteChange(const QPalette &)

    \internal
    \obsolete
*/

/*!
    \fn void QWidget::fontChange(const QFont &)

    \internal
    \obsolete
*/

/*!
    \fn void QWidget::windowActivationChange(bool)

    \internal
    \obsolete
*/

/*!
    \fn void QWidget::languageChange()

    \obsolete
*/

/*!
    \fn void QWidget::styleChange(QStyle& style)

    \internal
    \obsolete
*/

/*!
    Disables widget input events if \a disable is true; otherwise
    enables input events.

    See the \l enabled documentation for more information.

    \sa isEnabledTo(), QKeyEvent, QMouseEvent, changeEvent()
*/
void QWidget::setDisabled(bool disable)
{
    setEnabled(!disable);
}

/*!
    \property QWidget::frameGeometry
    \brief geometry of the widget relative to its parent including any
    window frame

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \sa geometry() x() y() pos()
*/
QRect QWidget::frameGeometry() const
{
    Q_D(const QWidget);
    if (isWindow() && ! (windowType() == Qt::Popup)) {
        QRect fs = d->frameStrut();
        return QRect(data->crect.x() - fs.left(),
                     data->crect.y() - fs.top(),
                     data->crect.width() + fs.left() + fs.right(),
                     data->crect.height() + fs.top() + fs.bottom());
    }
    return data->crect;
}

/*!
    \property QWidget::x

    \brief the x coordinate of the widget relative to its parent including
    any window frame

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    By default, this property has a value of 0.

    \sa frameGeometry, y, pos
*/
int QWidget::x() const
{
    Q_D(const QWidget);
    if (isWindow() && ! (windowType() == Qt::Popup))
        return data->crect.x() - d->frameStrut().left();
    return data->crect.x();
}

/*!
    \property QWidget::y
    \brief the y coordinate of the widget relative to its parent and
    including any window frame

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    By default, this property has a value of 0.

    \sa frameGeometry, x, pos
*/
int QWidget::y() const
{
    Q_D(const QWidget);
    if (isWindow() && ! (windowType() == Qt::Popup))
        return data->crect.y() - d->frameStrut().top();
    return data->crect.y();
}

/*!
    \property QWidget::pos
    \brief the position of the widget within its parent widget

    If the widget is a window, the position is that of the widget on
    the desktop, including its frame.

    When changing the position, the widget, if visible, receives a
    move event (moveEvent()) immediately. If the widget is not
    currently visible, it is guaranteed to receive an event before it
    is shown.

    By default, this property contains a position that refers to the
    origin.

    \warning Calling move() or setGeometry() inside moveEvent() can
    lead to infinite recursion.

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    \sa frameGeometry, size x(), y()
*/
QPoint QWidget::pos() const
{
    Q_D(const QWidget);
    if (isWindow() && ! (windowType() == Qt::Popup)) {
        QRect fs = d->frameStrut();
        return QPoint(data->crect.x() - fs.left(), data->crect.y() - fs.top());
    }
    return data->crect.topLeft();
}

/*!
    \property QWidget::geometry
    \brief the geometry of the widget relative to its parent and
    excluding the window frame

    When changing the geometry, the widget, if visible, receives a
    move event (moveEvent()) and/or a resize event (resizeEvent())
    immediately. If the widget is not currently visible, it is
    guaranteed to receive appropriate events before it is shown.

    The size component is adjusted if it lies outside the range
    defined by minimumSize() and maximumSize().

    \warning Calling setGeometry() inside resizeEvent() or moveEvent()
    can lead to infinite recursion.

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \sa frameGeometry(), rect(), move(), resize(), moveEvent(),
        resizeEvent(), minimumSize(), maximumSize()
*/

/*!
    \property QWidget::normalGeometry

    \brief the geometry of the widget as it will appear when shown as
    a normal (not maximized or full screen) top-level widget

    For child widgets this property always holds an empty rectangle.

    By default, this property contains an empty rectangle.

    \sa QWidget::windowState(), QWidget::geometry
*/

/*!
    \property QWidget::size
    \brief the size of the widget excluding any window frame

    If the widget is visible when it is being resized, it receives a resize event
    (resizeEvent()) immediately. If the widget is not currently
    visible, it is guaranteed to receive an event before it is shown.

    The size is adjusted if it lies outside the range defined by
    minimumSize() and maximumSize().

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \warning Calling resize() or setGeometry() inside resizeEvent() can
    lead to infinite recursion.

    \note Setting the size to \c{QSize(0, 0)} will cause the widget to not
    appear on screen. This also applies to windows.

    \sa pos, geometry, minimumSize, maximumSize, resizeEvent(), adjustSize()
*/

/*!
    \property QWidget::width
    \brief the width of the widget excluding any window frame

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    \note Do not use this function to find the width of a screen on
    a \l{QDesktopWidget}{multiple screen desktop}. Read
    \l{QDesktopWidget#Screen Geometry}{this note} for details.

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \sa geometry, height, size
*/

/*!
    \property QWidget::height
    \brief the height of the widget excluding any window frame

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    \note Do not use this function to find the height of a screen
    on a \l{QDesktopWidget}{multiple screen desktop}. Read
    \l{QDesktopWidget#Screen Geometry}{this note} for details.

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \sa geometry, width, size
*/

/*!
    \property QWidget::rect
    \brief the internal geometry of the widget excluding any window
    frame

    The rect property equals QRect(0, 0, width(), height()).

    See the \l{Window Geometry} documentation for an overview of geometry
    issues with windows.

    By default, this property contains a value that depends on the user's
    platform and screen geometry.

    \sa size
*/


QRect QWidget::normalGeometry() const
{
    Q_D(const QWidget);
    if (!d->extra || !d->extra->topextra)
        return QRect();

    if (!isMaximized() && !isFullScreen())
        return geometry();

    return d->topData()->normalGeometry;
}


/*!
    \property QWidget::childrenRect
    \brief the bounding rectangle of the widget's children

    Hidden children are excluded.

    By default, for a widget with no children, this property contains a
    rectangle with zero width and height located at the origin.

    \sa childrenRegion() geometry()
*/

QRect QWidget::childrenRect() const
{
    Q_D(const QWidget);
    QRect r(0, 0, 0, 0);
    for (int i = 0; i < d->children.size(); ++i) {
        QWidget *w = qobject_cast<QWidget *>(d->children.at(i));
        if (w && !w->isWindow() && !w->isHidden())
            r |= w->geometry();
    }
    return r;
}

/*!
    \property QWidget::childrenRegion
    \brief the combined region occupied by the widget's children

    Hidden children are excluded.

    By default, for a widget with no children, this property contains an
    empty region.

    \sa childrenRect() geometry() mask()
*/

QRegion QWidget::childrenRegion() const
{
    Q_D(const QWidget);
    QRegion r;
    for (int i = 0; i < d->children.size(); ++i) {
        QWidget *w = qobject_cast<QWidget *>(d->children.at(i));
        if (w && !w->isWindow() && !w->isHidden()) {
            QRegion mask = w->mask();
            if (mask.isEmpty())
                r |= w->geometry();
            else
                r |= mask.translated(w->pos());