QEvent(3qt)

NAME
QEvent - Base class of all event classes. Event objects contain event parameters

#include <qevent.h>

Inherits Qt.

Inherited by QChildEvent, QCloseEvent, QCustomEvent, QDragLeaveEvent, QDragResponseEvent, QDropEvent, QFocusEvent, QHideEvent, QKeyEvent, QMouseEvent, QMoveEvent, QPaintEvent, QResizeEvent, QShowEvent, QTimerEvent and QWheelEvent.

  Public Members
enum Type { None = 0, Timer = 1, MouseButtonPress = 2, MouseButtonRelease = 3, MouseButtonDblClick= 4, MouseMove = 5, KeyPress = 6, KeyRelease = 7, FocusIn = 8, FocusOut = 9, Enter = 10, Leave = 11, Paint = 12, Move = 13, Resize = 14, Create = 15, Destroy = 16, Show = 17, Hide = 18, Close = 19, Quit = 20, Reparent = 21, ShowMinimized = 22, ShowNormal = 23, WindowActivate = 24, WindowDeactivate = 25, ShowToParent = 26, HideToParent = 27, ShowMaximized = 28, Accel = 30, Wheel = 31, AccelAvailable = 32, CaptionChange = 33, IconChange = 34, ParentFontChange = 35, ApplicationFontChange = 36, ParentPaletteChange = 37, ApplicationPaletteChange = 38, Clipboard = 40, Speech = 42, SockAct = 50, AccelOverride = 51, DragEnter = 60, DragMove = 61, DragLeave = 62, Drop = 63, DragResponse = 64, ChildInserted = 70, ChildRemoved = 71, LayoutHint = 72, ShowWindowRequest = 73, ActivateControl = 80, DeactivateControl = 81, User = 1000 }
QEvent ( Type type )
virtual ~QEvent ()
Type type () const

DESCRIPTION
The QEvent class is base class of all event classes. Event objects contain event parameters.

The main event loop of Qt (QApplication::exec()) fetches native window system events from the event queue, translates them into QEvent and sends the translated events to QObjects.

Generally, events come from the underlying window system, but it is also possible to manually send events through the QApplication class using QApplication::sendEvent() and QApplication::postEvent().

QObject received events by having its QObject::event() function called. The function can be reimplemented in subclasses to customize event handling and add additional event types. QWidget::event() is a notable example. By default, events are dispatched to event handlers like QObject::timerEvent() and QWidget::mouseMoveEvent(). QObject::installEventFilter() allows an object to intercept events to another object.

The basic QEvent only contains an event type parameter. Subclasses of QEvent contain additional parameters that describe the particular event.

See also QObject::event(), QObject::installEventFilter(), QWidget::event(), QApplication::sendEvent(), QAppilcation::postEvent() and QApplication::processEvents().

  Member Type Documentation

QEvent::Type
This enum type defines the valid event types in Qt. The currently defined event types, and the specialized classes for each type, are:

None - not an event

Timer - regular timer events, QTimerEvent

MouseButtonPress - mouse press, QMouseEvent

MouseButtonRelease - mouse release, QMouseEvent

MouseButtonDblClick - mouse press again, QMouseEvent

MouseMove - mouse move, QMouseEvent

KeyPress - key press (including e.g. shift), QKeyEvent

KeyRelease - key release, QKeyEvent

FocusIn - widget gains keyboard focus, QFocusEvent

FocusOut - widget loses keyboard focus, QFocusEvent

Enter - mouse enters widget's space

Leave - mouse leaves widget's soace

Paint - screen update necessary, QPaintEvent

Move - widget's position changed, QMoveEvent

Resize - widget's size changed, QResizeEvent

Show - widget was shown on screen, QShowEvent

Hide - widget was removed from screen, QHideEvent

Close - widget was closed (permanently), QCloseEvent

Accel - key press in child, for shortcut key handling, QKeyEvent

Wheel - mouse wheel rolled, QWheelEvent

AccelAvailable - an internal event used by Qt on some platforms.

AccelOverride - key press in child, for overriding shortcut key handling, QKeyEvent

WindowActivate - the window was activated

WindowDeactivate - the window was deactivated

CaptionChange - widget's caption changed

IconChange - widget's icon changed

ParentFontChange - the font of the parent widget changed.

ApplicationFontChange - the default application font changed.

ParentPaletteChange - the palette of the parent widget changed.

ApplicationPaletteChange - the default application palette changed.

Clipboard - system clipboard contents have changed

SockAct - socket activated, used to implement QSocketNotifier

DragEnter - drag-and-drop enters widget, QDragEnterEvent

DragMove - drag-and-drop in progress, QDragMoveEvent

DragLeave - drag-and-drop leaves widget, QDragLeaveEvent

Drop - drag-and-drop is completed, QDropEvent

DragResponse - an internal event used by Qt on some platforms.

ChildInserted - object gets a child, QChildEvent

ChildRemoved - object loses a child, QChildEvent

LayoutHint - a widget child has changed layout properties

ActivateControl - an internal event used by Qt on some platforms.

DeactivateControl - an internal event used by Qt on some platforms.

Quit - reserved

Create - reserved

Destroy - reserved

Reparent - reserved

Configure - reserved

ConfigureLayout - reserved

User - user defined event

MEMBER FUNCTION DOCUMENTATION

QEvent::QEvent ( Type type )
Contructs an event object with a type.

QEvent::~QEvent () [virtual]
Destructs the event. If it was posted, it will be removed from the list of events to be posted.

QEvent::Type QEvent::type() const
Returns the event type.

SEE ALSO
http://doc.trolltech.com/qevent.html http://www.trolltech.com/faq/tech.html

COPYRIGHT
Copyright 1992-2001 Trolltech AS, http://www.trolltech.com. See the license file included in the distribution for a complete license statement.

AUTHOR
Generated automatically from the source code.

BUGS
If you find a bug in Qt, please report it as described in http://doc.trolltech.com/bughowto.html. Good bug reports make our job much simpler. Thank you.

In case of content or formattting problems with this manual page, please report them to qt-bugs@trolltech.com. Please include the name of the manual page (qevent.3qt) and the Qt version (2.3.1).