qwidget.cpp

奇趣公司比较新的qt/emd版本

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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"
#endif
#if defined(Q_WS_QWS)
# include "qwsmanager_qws.h"
# include "qpaintengine.h" // for PorterDuff
# include "private/qwindowsurface_qws_p.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 "qinputcontext.h"

#ifdef 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/qwindowsurface_p.h>
#ifndef Q_WS_MAC
# include <private/qbackingstore_p.h>
#else
# include <private/qpaintengine_mac_p.h>
#endif

#include "qwidget_p.h"
#include "qaction_p.h"
#include "qlayout_p.h"

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


QWidgetPrivate::QWidgetPrivate(int version) :
        QObjectPrivate(version), extra(0), focus_child(0)
        ,layout(0)
        ,leftmargin(0), topmargin(0), rightmargin(0), bottommargin(0)
        ,leftLayoutItemMargin(0), topLayoutItemMargin(0), rightLayoutItemMargin(0)
        ,bottomLayoutItemMargin(0)
        ,fg_role(QPalette::NoRole)
        ,bg_role(QPalette::NoRole)
        ,hd(0)
#ifdef Q_RATE_LIMIT_PAINTING
        ,timerId(-1)
#endif
#if defined(Q_WS_X11)
        ,picture(0)
#endif
#ifdef Q_WS_MAC
        ,isGLWidget(0)
#endif
        ,polished(0)

        , size_policy(QSizePolicy::Preferred, QSizePolicy::Preferred)
{
    if (!qApp) {
        qFatal("QWidget: Must construct a QApplication before a QPaintDevice");
        return;
    }

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

#ifdef Q_WIDGET_CACHE_OPAQUEREGIONS
    dirtyOpaqueChildren = true;
#endif

    isWidget = true;
    memset(high_attributes, 0, sizeof(high_attributes));
#ifdef QWIDGET_EXTRA_DEBUG
    static int count = 0;
    qDebug() << "widgets" << ++count;
#endif
}


QWidgetPrivate::~QWidgetPrivate()
{
#ifdef Q_WIDGET_USE_DIRTYLIST
    if (!dirty.isEmpty()) {
        Q_Q(QWidget);

        QWidgetBackingStore *bs = maybeBackingStore();
        if (bs)
            bs->removeDirtyWidget(q);
    }
#endif

    if (extra)
        deleteExtra();
}


/*!
    \internal
    This is an internal function, you should never call this.

    This function is called to focus associated input context. The
    code intends to eliminate duplicate focus for the context even if
    the context is shared between widgets

    \sa QInputContext::setFocus()
 */
void QWidgetPrivate::focusInputContext()
{
#ifndef QT_NO_IM
    Q_Q(QWidget);
    QInputContext *qic = q->inputContext();
    if (qic) {
        if(qic->focusWidget() != q)
            qic->setFocusWidget(q);
    }
#endif // QT_NO_IM
}

/*!
    \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
                QMoveEvent e(r.topLeft(), oldp);
                QApplication::sendEvent(w, &e);
            }
        }
    }
}


/*!
    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;

#ifndef QT_NO_IM
    if (d->ic)
        return d->ic;
#endif
    return qApp->inputContext();
}

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

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


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

    \sa QInputContext, 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 available in Qtopia Core only.

    \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 available in Qtopia Core only.

    \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 will cause Qt to fill the background
    using the widget's background role before invoking
    the paint event. The background role is defined by the widget's
    \l{palette}.

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

    \warning Do not set this property when using \l{Qt Style Sheets}.
    When using style sheets, the widget is always filled with the "background"
    property. The "border-radius" property may be used to clip the background.

    \sa Qt::WA_OpaquePaintEvent, Qt::WA_NoSystemBackground
*/
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
    \mainclass

    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 isn't 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, and are displayed within