qevent.cpp

奇趣公司比较新的qt/emd版本

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#include "qevent.h"
#include "qcursor.h"
#include "qapplication.h"
#include "private/qapplication_p.h"
#include "private/qkeysequence_p.h"
#include "qwidget.h"
#include "qdebug.h"
#include "qmime.h"
#include "qdnd_p.h"
#include "qevent_p.h"

/*!
    \class QInputEvent
    \ingroup events

    \brief The QInputEvent class is the base class for events that
    describe user input.
*/

/*!
  \internal
*/
QInputEvent::QInputEvent(Type type, Qt::KeyboardModifiers modifiers)
    : QEvent(type), modState(modifiers)
{}

/*!
  \internal
*/
QInputEvent::~QInputEvent()
{
}

/*!
    \fn Qt::KeyboardModifiers QInputEvent::modifiers() const

    Returns the keyboard modifier flags that existed immediately
    before the event occurred.

    \sa QApplication::keyboardModifiers()
*/

/*!
    \class QMouseEvent
    \ingroup events

    \brief The QMouseEvent class contains parameters that describe a mouse event.

    Mouse events occur when a mouse button is pressed or released
    inside a widget, or when the mouse cursor is moved.

    Mouse move events will occur only when a mouse button is pressed
    down, unless mouse tracking has been enabled with
    QWidget::setMouseTracking().

    Qt automatically grabs the mouse when a mouse button is pressed
    inside a widget; the widget will continue to receive mouse events
    until the last mouse button is released.

    A mouse event contains a special accept flag that indicates
    whether the receiver wants the event. You should call ignore() if
    the mouse event is not handled by your widget. A mouse event is
    propagated up the parent widget chain until a widget accepts it
    with accept(), or an event filter consumes it.

    The state of the keyboard modifier keys can be found by calling the
    \l{QInputEvent::modifiers()}{modifiers()} function, inhertied from
    QInputEvent.

    The functions pos(), x(), and y() give the cursor position
    relative to the widget that receives the mouse event. If you
    move the widget as a result of the mouse event, use the global
    position returned by globalPos() to avoid a shaking motion.

    The QWidget::setEnabled() function can be used to enable or
    disable mouse and keyboard events for a widget.

    Reimplement the QWidget event handlers, QWidget::mousePressEvent(),
    QWidget::mouseReleaseEvent(), QWidget::mouseDoubleClickEvent(),
    and QWidget::mouseMoveEvent() to receive mouse events in your own
    widgets.

    \sa QWidget::setMouseTracking() QWidget::grabMouse()
    QCursor::pos()
*/

/*!
    Constructs a mouse event object.

    The \a type parameter must be one of QEvent::MouseButtonPress,
    QEvent::MouseButtonRelease, QEvent::MouseButtonDblClick,
    or QEvent::MouseMove.

    The \a position is the mouse cursor's position relative to the
    receiving widget.
    The \a button that caused the event is given as a value from
    the Qt::MouseButton enum. If the event \a type is
    \l MouseMove, the appropriate button for this event is Qt::NoButton.
    The mouse and keyboard states at the time of the event are specified by
    \a buttons and \a modifiers.

    The globalPos() is initialized to QCursor::pos(), which may not
    be appropriate. Use the other constructor to specify the global
    position explicitly.
*/

QMouseEvent::QMouseEvent(Type type, const QPoint &position, Qt::MouseButton button,
                         Qt::MouseButtons buttons, Qt::KeyboardModifiers modifiers)
    : QInputEvent(type, modifiers), p(position), b(button), mouseState(buttons)
{
    g = QCursor::pos();
}

/*!
    \internal
*/
QMouseEvent::~QMouseEvent()
{
}

#ifdef QT3_SUPPORT
/*!
    Use QMouseEvent(\a type, \a pos, \a button, \c buttons, \c
    modifiers) instead, where \c buttons is \a state &
    Qt::MouseButtonMask and \c modifiers is \a state &
    Qt::KeyButtonMask.
*/
QMouseEvent::QMouseEvent(Type type, const QPoint &pos, Qt::ButtonState button, int state)
    : QInputEvent(type), p(pos), b((Qt::MouseButton)button)
{
    g = QCursor::pos();
    mouseState = Qt::MouseButtons((state ^ b) & Qt::MouseButtonMask);
    modState = Qt::KeyboardModifiers(state & (int)Qt::KeyButtonMask);
}

/*!
    Use QMouseEvent(\a type, \a pos, \a globalPos, \a button,
    \c buttons, \c modifiers) instead, where
    \c buttons is \a state & Qt::MouseButtonMask and
    \c modifiers is \a state & Qt::KeyButtonMask.
*/
QMouseEvent::QMouseEvent(Type type, const QPoint &pos, const QPoint &globalPos,
                         Qt::ButtonState button, int state)
    : QInputEvent(type), p(pos), g(globalPos), b((Qt::MouseButton)button)
{
    mouseState = Qt::MouseButtons((state ^ b) & Qt::MouseButtonMask);
    modState = Qt::KeyboardModifiers(state & (int)Qt::KeyButtonMask);
}
#endif


/*!
    Constructs a mouse event object.

    The \a type parameter must be QEvent::MouseButtonPress,
    QEvent::MouseButtonRelease, QEvent::MouseButtonDblClick,
    or QEvent::MouseMove.

    The \a pos is the mouse cursor's position relative to the
    receiving widget. The cursor's position in global coordinates is
    specified by \a globalPos.  The \a button that caused the event is
    given as a value from the \l Qt::MouseButton enum. If the event \a
    type is \l MouseMove, the appropriate button for this event is
    Qt::NoButton. \a buttons is the state of all buttons at the
    time of the event, \a modifiers the state of all keyboard
    modifiers.

*/
QMouseEvent::QMouseEvent(Type type, const QPoint &pos, const QPoint &globalPos,
                         Qt::MouseButton button, Qt::MouseButtons buttons,
                         Qt::KeyboardModifiers modifiers)
    : QInputEvent(type, modifiers), p(pos), g(globalPos), b(button), mouseState(buttons)
{}

/*!
    \fn const QPoint &QMouseEvent::pos() const

    Returns the position of the mouse cursor, relative to the widget
    that received the event.

    If you move the widget as a result of the mouse event, use the
    global position returned by globalPos() to avoid a shaking
    motion.

    \sa x() y() globalPos()
*/

/*!
    \fn const QPoint &QMouseEvent::globalPos() const

    Returns the global position of the mouse cursor \e{at the time
    of the event}. This is important on asynchronous window systems
    like X11. Whenever you move your widgets around in response to
    mouse events, globalPos() may differ a lot from the current
    pointer position QCursor::pos(), and from
    QWidget::mapToGlobal(pos()).

    \sa globalX() globalY()
*/

/*!
    \fn int QMouseEvent::x() const

    Returns the x position of the mouse cursor, relative to the
    widget that received the event.

    \sa y() pos()
*/

/*!
    \fn int QMouseEvent::y() const

    Returns the y position of the mouse cursor, relative to the
    widget that received the event.

    \sa x() pos()
*/

/*!
    \fn int QMouseEvent::globalX() const

    Returns the global x position of the mouse cursor at the time of
    the event.

    \sa globalY() globalPos()
*/

/*!
    \fn int QMouseEvent::globalY() const

    Returns the global y position of the mouse cursor at the time of
    the event.

    \sa globalX() globalPos()
*/

/*!
    \fn Qt::MouseButton QMouseEvent::button() const

    Returns the button that caused the event.

    Note that the returned value is always Qt::NoButton for mouse
    move events.

    \sa buttons() Qt::MouseButton
*/

/*!
    \fn Qt::MouseButton QMouseEvent::buttons() const

    Returns the button state when the event was generated. The button
    state is a combination of Qt::LeftButton, Qt::RightButton,
    Qt::MidButton using the OR operator. For mouse move events,
    this is all buttons that are pressed down. For mouse press and
    double click events this includes the button that caused the
    event. For mouse release events this excludes the button that
    caused the event.

    \sa button() Qt::MouseButton
*/


/*!
    \fn Qt::ButtonState QMouseEvent::state() const

    Returns the button state immediately before the event was
    generated. The button state is a combination of mouse buttons
    (see Qt::ButtonState) and keyboard modifiers (Qt::MouseButtons).

    Use buttons() and/or modifiers() instead. Be aware that buttons()
    return the state immediately \e after the event was generated.
*/

/*!
    \fn Qt::ButtonState QMouseEvent::stateAfter() const

    Returns the button state immediately after the event was
    generated. The button state is a combination of mouse buttons
    (see Qt::ButtonState) and keyboard modifiers (Qt::MouseButtons).

    Use buttons() and/or modifiers() instead.
*/


/*!
    \class QHoverEvent
    \ingroup events

    \brief The QHoverEvent class contains parameters that describe a mouse event.

    Mouse events occur when a mouse cursor is moved into, out of, or within a
    widget, and if the widget has the Qt::WA_Hover attribute.

    The function pos() gives the current cursor position, while oldPos() gives
    the old mouse position.
*/

/*!
    \fn const QPoint &QHoverEvent::pos() const

    Returns the position of the mouse cursor, relative to the widget
    that received the event.

    On QEvent::HoverLeave events, this position will always be
    QPoint(-1, -1).

    \sa oldPos()
*/

/*!
    \fn const QPoint &QHoverEvent::oldPos() const

    Returns the previous position of the mouse cursor, relative to the widget
    that received the event. If there is no previous position, oldPos() will
    return the same position as pos().

    On QEvent::HoverEnter events, this position will always be
    QPoint(-1, -1).

    \sa pos()
*/

/*!
    Constructs a hover event object.

    The \a type parameter must be QEvent::HoverEnter,
    QEvent::HoverLeave, or QEvent::HoverMove.

    The \a pos is the current mouse cursor's position relative to the
    receiving widget, while \a oldPos is the previous mouse cursor's
    position relative to the receiving widget.
*/
QHoverEvent::QHoverEvent(Type type, const QPoint &pos, const QPoint &oldPos)
    : QEvent(type), p(pos), op(oldPos)
{
}

/*!
    \internal
*/
QHoverEvent::~QHoverEvent()
{
}


/*!
    \class QWheelEvent
    \brief The QWheelEvent class contains parameters that describe a wheel event.

    \ingroup events

    Wheel events are sent to the widget under the mouse cursor, but
    if that widget does not handle the event they are sent to the
    focus widget. The rotation distance is provided by delta().
    The functions pos() and globalPos() return the mouse cursor's
    location at the time of the event.

    A wheel event contains a special accept flag that indicates
    whether the receiver wants the event. You should call ignore() if
    you do not handle the wheel event; this ensures that it will be
    sent to the parent widget.

    The QWidget::setEnabled() function can be used to enable or
    disable mouse and keyboard events for a widget.

    The event handler QWidget::wheelEvent() receives wheel events.

    \sa QMouseEvent QWidget::grabMouse()
*/

/*!
    \fn Qt::MouseButtons QWheelEvent::buttons() const

    Returns the mouse state when the event occurred.
*/

/*!
    \fn Qt::Orientation QWheelEvent::orientation() const

    Returns the wheel's orientation.
*/

/*!
    Constructs a wheel event object.

    The position, \a pos, is the location of the mouse cursor within
    the widget. The globalPos() is initialized to QCursor::pos()
    which is usually, but not always, correct.
    Use the other constructor if you need to specify the global
    position explicitly.

    The \a buttons describe the state of the mouse buttons at the time