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40
41#include "qcoreevent.h"
42#include "qcoreapplication.h"
43#include "qcoreapplication_p.h"
44
45#include "qbasicatomic.h"
46
47#include <qtcore_tracepoints_p.h>
48
49#include <limits>
50
51QT_BEGIN_NAMESPACE
52
53/*!
54 \class QEvent
55 \inmodule QtCore
56 \brief The QEvent class is the base class of all
57 event classes. Event objects contain event parameters.
58
59 \ingroup events
60
61 Qt's main event loop (QCoreApplication::exec()) fetches native
62 window system events from the event queue, translates them into
63 QEvents, and sends the translated events to \l{QObject}s.
64
65 In general, events come from the underlying window system
66 (spontaneous() returns \c true), but it is also possible to manually
67 send events using QCoreApplication::sendEvent() and
68 QCoreApplication::postEvent() (spontaneous() returns \c false).
69
70 \l {QObject}{QObjects} receive events by having their QObject::event() function
71 called. The function can be reimplemented in subclasses to
72 customize event handling and add additional event types;
73 QWidget::event() is a notable example. By default, events are
74 dispatched to event handlers like QObject::timerEvent() and
75 QWidget::mouseMoveEvent(). QObject::installEventFilter() allows an
76 object to intercept events destined for another object.
77
78 The basic QEvent contains only an event type parameter and an
79 "accept" flag. The accept flag set with accept(), and cleared
80 with ignore(). It is set by default, but don't rely on this as
81 subclasses may choose to clear it in their constructor.
82
83 Subclasses of QEvent contain additional parameters that describe
84 the particular event.
85
86 \sa QObject::event(), QObject::installEventFilter(),
87 QCoreApplication::sendEvent(),
88 QCoreApplication::postEvent(), QCoreApplication::processEvents()
89*/
90
91
92/*!
93 \enum QEvent::Type
94
95 This enum type defines the valid event types in Qt. The event
96 types and the specialized classes for each type are as follows:
97
98 \value None Not an event.
99 \value ActionAdded A new action has been added (QActionEvent).
100 \value ActionChanged An action has been changed (QActionEvent).
101 \value ActionRemoved An action has been removed (QActionEvent).
102 \value ActivationChange A widget's top-level window activation state has changed.
103 \value ApplicationActivate This enum has been deprecated. Use ApplicationStateChange instead.
104 \value ApplicationActivated This enum has been deprecated. Use ApplicationStateChange instead.
105 \value ApplicationDeactivate This enum has been deprecated. Use ApplicationStateChange instead.
106 \value ApplicationFontChange The default application font has changed.
107 \value ApplicationLayoutDirectionChange The default application layout direction has changed.
108 \value ApplicationPaletteChange The default application palette has changed.
109 \value ApplicationStateChange The state of the application has changed.
110 \value ApplicationWindowIconChange The application's icon has changed.
111 \value ChildAdded An object gets a child (QChildEvent).
112 \value ChildPolished A widget child gets polished (QChildEvent).
113 \value ChildRemoved An object loses a child (QChildEvent).
114 \value Clipboard The clipboard contents have changed.
115 \value Close Widget was closed (QCloseEvent).
116 \value CloseSoftwareInputPanel A widget wants to close the software input panel (SIP).
117 \value ContentsRectChange The margins of the widget's content rect changed.
118 \value ContextMenu Context popup menu (QContextMenuEvent).
119 \value CursorChange The widget's cursor has changed.
120 \value DeferredDelete The object will be deleted after it has cleaned up (QDeferredDeleteEvent)
121 \value DragEnter The cursor enters a widget during a drag and drop operation (QDragEnterEvent).
122 \value DragLeave The cursor leaves a widget during a drag and drop operation (QDragLeaveEvent).
123 \value DragMove A drag and drop operation is in progress (QDragMoveEvent).
124 \value Drop A drag and drop operation is completed (QDropEvent).
125 \value DynamicPropertyChange A dynamic property was added, changed, or removed from the object.
126 \value EnabledChange Widget's enabled state has changed.
127 \value Enter Mouse enters widget's boundaries (QEnterEvent).
128 \value EnterEditFocus An editor widget gains focus for editing. \c QT_KEYPAD_NAVIGATION must be defined.
129 \value EnterWhatsThisMode Send to toplevel widgets when the application enters "What's This?" mode.
130 \value Expose Sent to a window when its on-screen contents are invalidated and need to be flushed from the backing store.
131 \value FileOpen File open request (QFileOpenEvent).
132 \value FocusIn Widget or Window gains keyboard focus (QFocusEvent).
133 \value FocusOut Widget or Window loses keyboard focus (QFocusEvent).
134 \value FocusAboutToChange Widget or Window focus is about to change (QFocusEvent)
135 \value FontChange Widget's font has changed.
136 \value Gesture A gesture was triggered (QGestureEvent).
137 \value GestureOverride A gesture override was triggered (QGestureEvent).
138 \value GrabKeyboard Item gains keyboard grab (QGraphicsItem only).
139 \value GrabMouse Item gains mouse grab (QGraphicsItem only).
140 \value GraphicsSceneContextMenu Context popup menu over a graphics scene (QGraphicsSceneContextMenuEvent).
141 \value GraphicsSceneDragEnter The cursor enters a graphics scene during a drag and drop operation (QGraphicsSceneDragDropEvent).
142 \value GraphicsSceneDragLeave The cursor leaves a graphics scene during a drag and drop operation (QGraphicsSceneDragDropEvent).
143 \value GraphicsSceneDragMove A drag and drop operation is in progress over a scene (QGraphicsSceneDragDropEvent).
144 \value GraphicsSceneDrop A drag and drop operation is completed over a scene (QGraphicsSceneDragDropEvent).
145 \value GraphicsSceneHelp The user requests help for a graphics scene (QHelpEvent).
146 \value GraphicsSceneHoverEnter The mouse cursor enters a hover item in a graphics scene (QGraphicsSceneHoverEvent).
147 \value GraphicsSceneHoverLeave The mouse cursor leaves a hover item in a graphics scene (QGraphicsSceneHoverEvent).
148 \value GraphicsSceneHoverMove The mouse cursor moves inside a hover item in a graphics scene (QGraphicsSceneHoverEvent).
149 \value GraphicsSceneMouseDoubleClick Mouse press again (double click) in a graphics scene (QGraphicsSceneMouseEvent).
150 \value GraphicsSceneMouseMove Move mouse in a graphics scene (QGraphicsSceneMouseEvent).
151 \value GraphicsSceneMousePress Mouse press in a graphics scene (QGraphicsSceneMouseEvent).
152 \value GraphicsSceneMouseRelease Mouse release in a graphics scene (QGraphicsSceneMouseEvent).
153 \value GraphicsSceneMove Widget was moved (QGraphicsSceneMoveEvent).
154 \value GraphicsSceneResize Widget was resized (QGraphicsSceneResizeEvent).
155 \value GraphicsSceneWheel Mouse wheel rolled in a graphics scene (QGraphicsSceneWheelEvent).
156 \value Hide Widget was hidden (QHideEvent).
157 \value HideToParent A child widget has been hidden.
158 \value HoverEnter The mouse cursor enters a hover widget (QHoverEvent).
159 \value HoverLeave The mouse cursor leaves a hover widget (QHoverEvent).
160 \value HoverMove The mouse cursor moves inside a hover widget (QHoverEvent).
161 \value IconDrag The main icon of a window has been dragged away (QIconDragEvent).
162 \value IconTextChange Widget's icon text has been changed. (Deprecated)
163 \value InputMethod An input method is being used (QInputMethodEvent).
164 \value InputMethodQuery A input method query event (QInputMethodQueryEvent)
165 \value KeyboardLayoutChange The keyboard layout has changed.
166 \value KeyPress Key press (QKeyEvent).
167 \value KeyRelease Key release (QKeyEvent).
168 \value LanguageChange The application translation changed.
169 \value LayoutDirectionChange The direction of layouts changed.
170 \value LayoutRequest Widget layout needs to be redone.
171 \value Leave Mouse leaves widget's boundaries.
172 \value LeaveEditFocus An editor widget loses focus for editing. QT_KEYPAD_NAVIGATION must be defined.
173 \value LeaveWhatsThisMode Send to toplevel widgets when the application leaves "What's This?" mode.
174 \value LocaleChange The system locale has changed.
175 \value NonClientAreaMouseButtonDblClick A mouse double click occurred outside the client area (QMouseEvent).
176 \value NonClientAreaMouseButtonPress A mouse button press occurred outside the client area (QMouseEvent).
177 \value NonClientAreaMouseButtonRelease A mouse button release occurred outside the client area (QMouseEvent).
178 \value NonClientAreaMouseMove A mouse move occurred outside the client area (QMouseEvent).
179 \value MacSizeChange The user changed his widget sizes (\macos only).
180 \value MetaCall An asynchronous method invocation via QMetaObject::invokeMethod().
181 \value ModifiedChange Widgets modification state has been changed.
182 \value MouseButtonDblClick Mouse press again (QMouseEvent).
183 \value MouseButtonPress Mouse press (QMouseEvent).
184 \value MouseButtonRelease Mouse release (QMouseEvent).
185 \value MouseMove Mouse move (QMouseEvent).
186 \value MouseTrackingChange The mouse tracking state has changed.
187 \value Move Widget's position changed (QMoveEvent).
188 \value NativeGesture The system has detected a gesture (QNativeGestureEvent).
189 \value OrientationChange The screens orientation has changes (QScreenOrientationChangeEvent).
190 \value Paint Screen update necessary (QPaintEvent).
191 \value PaletteChange Palette of the widget changed.
192 \value ParentAboutToChange The widget parent is about to change.
193 \value ParentChange The widget parent has changed.
194 \value PlatformPanel A platform specific panel has been requested.
195 \value PlatformSurface A native platform surface has been created or is about to be destroyed (QPlatformSurfaceEvent).
196 \omitvalue Pointer
197 \value Polish The widget is polished.
198 \value PolishRequest The widget should be polished.
199 \value QueryWhatsThis The widget should accept the event if it has "What's This?" help (QHelpEvent).
200 \value ReadOnlyChange Widget's read-only state has changed (since Qt 5.4).
201 \value RequestSoftwareInputPanel A widget wants to open a software input panel (SIP).
202 \value Resize Widget's size changed (QResizeEvent).
203 \value ScrollPrepare The object needs to fill in its geometry information (QScrollPrepareEvent).
204 \value Scroll The object needs to scroll to the supplied position (QScrollEvent).
205 \value Shortcut Key press in child for shortcut key handling (QShortcutEvent).
206 \value ShortcutOverride Key press in child, for overriding shortcut key handling (QKeyEvent).
207 When a shortcut is about to trigger, \c ShortcutOverride
208 is sent to the active window. This allows clients (e.g. widgets)
209 to signal that they will handle the shortcut themselves, by
210 accepting the event. If the shortcut override is accepted, the
211 event is delivered as a normal key press to the focus widget.
212 Otherwise, it triggers the shortcut action, if one exists.
213 \value Show Widget was shown on screen (QShowEvent).
214 \value ShowToParent A child widget has been shown.
215 \value SockAct Socket activated, used to implement QSocketNotifier.
216 \omitvalue SockClose
217 \value StateMachineSignal A signal delivered to a state machine (QStateMachine::SignalEvent).
218 \value StateMachineWrapped The event is a wrapper for, i.e., contains, another event (QStateMachine::WrappedEvent).
219 \value StatusTip A status tip is requested (QStatusTipEvent).
220 \value StyleChange Widget's style has been changed.
221 \value TabletMove Wacom tablet move (QTabletEvent).
222 \value TabletPress Wacom tablet press (QTabletEvent).
223 \value TabletRelease Wacom tablet release (QTabletEvent).
224 \omitvalue OkRequest
225 \value TabletEnterProximity Wacom tablet enter proximity event (QTabletEvent), sent to QApplication.
226 \value TabletLeaveProximity Wacom tablet leave proximity event (QTabletEvent), sent to QApplication.
227 \value TabletTrackingChange The Wacom tablet tracking state has changed (since Qt 5.9).
228 \omitvalue ThemeChange
229 \value ThreadChange The object is moved to another thread. This is the last event sent to this object in the previous thread. See QObject::moveToThread().
230 \value Timer Regular timer events (QTimerEvent).
231 \value ToolBarChange The toolbar button is toggled on \macos.
232 \value ToolTip A tooltip was requested (QHelpEvent).
233 \value ToolTipChange The widget's tooltip has changed.
234 \value TouchBegin Beginning of a sequence of touch-screen or track-pad events (QTouchEvent).
235 \value TouchCancel Cancellation of touch-event sequence (QTouchEvent).
236 \value TouchEnd End of touch-event sequence (QTouchEvent).
237 \value TouchUpdate Touch-screen event (QTouchEvent).
238 \value UngrabKeyboard Item loses keyboard grab (QGraphicsItem only).
239 \value UngrabMouse Item loses mouse grab (QGraphicsItem, QQuickItem).
240 \value UpdateLater The widget should be queued to be repainted at a later time.
241 \value UpdateRequest The widget should be repainted.
242 \value WhatsThis The widget should reveal "What's This?" help (QHelpEvent).
243 \value WhatsThisClicked A link in a widget's "What's This?" help was clicked.
244 \value Wheel Mouse wheel rolled (QWheelEvent).
245 \value WinEventAct A Windows-specific activation event has occurred.
246 \value WindowActivate Window was activated.
247 \value WindowBlocked The window is blocked by a modal dialog.
248 \value WindowDeactivate Window was deactivated.
249 \value WindowIconChange The window's icon has changed.
250 \value WindowStateChange The \l{QWindow::windowState()}{window's state} (minimized, maximized or full-screen) has changed (QWindowStateChangeEvent).
251 \value WindowTitleChange The window title has changed.
252 \value WindowUnblocked The window is unblocked after a modal dialog exited.
253 \value WinIdChange The window system identifer for this native widget has changed.
254 \value ZOrderChange The widget's z-order has changed. This event is never sent to top level windows.
255
256 User events should have values between \c User and \c{MaxUser}:
257
258 \value User User-defined event.
259 \value MaxUser Last user event ID.
260
261 For convenience, you can use the registerEventType() function to
262 register and reserve a custom event type for your
263 application. Doing so will allow you to avoid accidentally
264 re-using a custom event type already in use elsewhere in your
265 application.
266
267 \omitvalue AcceptDropsChange
268 \omitvalue ActivateControl
269 \omitvalue Create
270 \omitvalue DeactivateControl
271 \omitvalue Destroy
272 \omitvalue DragResponse
273 \omitvalue EmbeddingControl
274 \omitvalue HelpRequest
275 \omitvalue Quit
276 \omitvalue ShowWindowRequest
277 \omitvalue Speech
278 \omitvalue Style
279 \omitvalue StyleAnimationUpdate
280 \omitvalue ZeroTimerEvent
281 \omitvalue ApplicationActivate
282 \omitvalue ApplicationActivated
283 \omitvalue ApplicationDeactivate
284 \omitvalue ApplicationDeactivated
285 \omitvalue MacGLWindowChange
286 \omitvalue NetworkReplyUpdated
287 \omitvalue FutureCallOut
288 \omitvalue NativeGesture
289 \omitvalue WindowChangeInternal
290 \omitvalue ScreenChangeInternal
291*/
292
293/*!
294 Contructs an event object of type \a type.
295*/
296QEvent::QEvent(Type type)
297 : d(nullptr), t(type), posted(false), spont(false), m_accept(true), m_inputEvent(false), m_pointerEvent(false)
298{
299 Q_TRACE(QEvent_ctor, this, t);
300}
301
302/*!
303 \internal
304 Copies the \a other event.
305*/
306QEvent::QEvent(const QEvent &other)
307 : d(other.d), t(other.t), posted(other.posted), spont(other.spont),
308 m_accept(other.m_accept), m_inputEvent(other.m_inputEvent), m_pointerEvent(other.m_pointerEvent)
309{
310 Q_TRACE(QEvent_ctor, this, t);
311 // if QEventPrivate becomes available, make sure to implement a
312 // virtual QEventPrivate *clone() const; function so we can copy here
313 Q_ASSERT_X(!d, "QEvent", "Impossible, this can't happen: QEventPrivate isn't defined anywhere");
314}
315
316/*!
317 \internal
318 \since 6.0
319 \fn QEvent::QEvent(Type type, QEvent::InputEventTag)
320
321 Constructs an event object of type \a type, setting the inputEvent flag to \c true.
322*/
323
324/*!
325 \internal
326 \since 6.0
327 \fn QEvent::QEvent(Type type, QEvent::PointerEventTag)
328
329 Constructs an event object of type \a type, setting the pointerEvent and
330 inputEvent flags to \c true.
331*/
332
333/*!
334 \internal
335 Attempts to copy the \a other event.
336
337 Copying events is a bad idea, yet some Qt 4 code does it (notably,
338 QApplication and the state machine).
339 */
340QEvent &QEvent::operator=(const QEvent &other)
341{
342 // if QEventPrivate becomes available, make sure to implement a
343 // virtual QEventPrivate *clone() const; function so we can copy here
344 Q_ASSERT_X(!other.d, "QEvent", "Impossible, this can't happen: QEventPrivate isn't defined anywhere");
345
346 t = other.t;
347 posted = other.posted;
348 spont = other.spont;
349 m_accept = other.m_accept;
350 return *this;
351}
352
353/*!
354 Destroys the event. If it was \l{QCoreApplication::postEvent()}{posted},
355 it will be removed from the list of events to be posted.
356*/
357
358QEvent::~QEvent()
359{
360 Q_TRACE(QEvent_dtor, this, t);
361 if (posted && QCoreApplication::instance())
362 QCoreApplicationPrivate::removePostedEvent(this);
363 Q_ASSERT_X(!d, "QEvent", "Impossible, this can't happen: QEventPrivate isn't defined anywhere");
364}
365
366
367/*!
368 \property QEvent::accepted
369 the accept flag of the event object
370
371 Setting the accept parameter indicates that the event receiver
372 wants the event. Unwanted events might be propagated to the parent
373 widget. By default, isAccepted() is set to true, but don't rely on
374 this as subclasses may choose to clear it in their constructor.
375
376 For convenience, the accept flag can also be set with accept(),
377 and cleared with ignore().
378
379 \note Accepting a QPointerEvent implicitly
380 \l {QEventPoint::setAccepted()}{accepts} all the
381 \l {QPointerEvent::points()}{points} that the event carries.
382*/
383
384/*!
385 \fn void QEvent::accept()
386
387 Sets the accept flag of the event object, the equivalent of
388 calling setAccepted(true).
389
390 Setting the accept parameter indicates that the event receiver
391 wants the event. Unwanted events might be propagated to the parent
392 widget.
393
394 \sa ignore()
395*/
396
397
398/*!
399 \fn void QEvent::ignore()
400
401 Clears the accept flag parameter of the event object, the
402 equivalent of calling setAccepted(false).
403
404 Clearing the accept parameter indicates that the event receiver
405 does not want the event. Unwanted events might be propagated to the
406 parent widget.
407
408 \sa accept()
409*/
410
411
412/*!
413 \fn QEvent::Type QEvent::type() const
414
415 Returns the event type.
416*/
417
418/*!
419 \fn bool QEvent::spontaneous() const
420
421 Returns \c true if the event originated outside the application (a
422 system event); otherwise returns \c false.
423*/
424
425/*!
426 \fn bool QEvent::isInputEvent() const
427 \since 6.0
428
429 Returns \c true if the event object is a QInputEvent or one of its
430 subclasses.
431*/
432
433/*!
434 \fn bool QEvent::isPointerEvent() const
435 \since 6.0
436
437 Returns \c true if the event object is a QPointerEvent or one of its
438 subclasses.
439*/
440
441namespace {
442template <size_t N>
443struct QBasicAtomicBitField {
444 enum {
445 BitsPerInt = std::numeric_limits<uint>::digits,
446 NumInts = (N + BitsPerInt - 1) / BitsPerInt,
447 NumBits = N
448 };
449
450 // This atomic int points to the next (possibly) free ID saving
451 // the otherwise necessary scan through 'data':
452 QBasicAtomicInteger<uint> next;
453 QBasicAtomicInteger<uint> data[NumInts];
454
455 bool allocateSpecific(int which) noexcept
456 {
457 QBasicAtomicInteger<uint> &entry = data[which / BitsPerInt];
458 const uint old = entry.loadRelaxed();
459 const uint bit = 1U << (which % BitsPerInt);
460 return !(old & bit) // wasn't taken
461 && entry.testAndSetRelaxed(old, old | bit); // still wasn't taken
462
463 // don't update 'next' here - it's unlikely that it will need
464 // to be updated, in the general case, and having 'next'
465 // trailing a bit is not a problem, as it is just a starting
466 // hint for allocateNext(), which, when wrong, will just
467 // result in a few more rounds through the allocateNext()
468 // loop.
469 }
470
471 int allocateNext() noexcept
472 {
473 // Unroll loop to iterate over ints, then bits? Would save
474 // potentially a lot of cmpxchgs, because we can scan the
475 // whole int before having to load it again.
476
477 // Then again, this should never execute many iterations, so
478 // leave like this for now:
479 for (uint i = next.loadRelaxed(); i < NumBits; ++i) {
480 if (allocateSpecific(i)) {
481 // remember next (possibly) free id:
482 const uint oldNext = next.loadRelaxed();
483 next.testAndSetRelaxed(oldNext, qMax(i + 1, oldNext));
484 return i;
485 }
486 }
487 return -1;
488 }
489};
490
491} // unnamed namespace
492
493typedef QBasicAtomicBitField<QEvent::MaxUser - QEvent::User + 1> UserEventTypeRegistry;
494
495static UserEventTypeRegistry userEventTypeRegistry;
496
497static inline int registerEventTypeZeroBased(int id) noexcept
498{
499 // if the type hint hasn't been registered yet, take it:
500 if (id < UserEventTypeRegistry::NumBits && id >= 0 && userEventTypeRegistry.allocateSpecific(id))
501 return id;
502
503 // otherwise, ignore hint:
504 return userEventTypeRegistry.allocateNext();
505}
506
507/*!
508 \since 4.4
509 \threadsafe
510
511 Registers and returns a custom event type. The \a hint provided
512 will be used if it is available, otherwise it will return a value
513 between QEvent::User and QEvent::MaxUser that has not yet been
514 registered. The \a hint is ignored if its value is not between
515 QEvent::User and QEvent::MaxUser.
516
517 Returns -1 if all available values are already taken or the
518 program is shutting down.
519*/
520int QEvent::registerEventType(int hint) noexcept
521{
522 const int result = registerEventTypeZeroBased(QEvent::MaxUser - hint);
523 return result < 0 ? -1 : QEvent::MaxUser - result ;
524}
525
526/*!
527 \class QTimerEvent
528 \inmodule QtCore
529 \brief The QTimerEvent class contains parameters that describe a
530 timer event.
531
532 \ingroup events
533
534 Timer events are sent at regular intervals to objects that have
535 started one or more timers. Each timer has a unique identifier. A
536 timer is started with QObject::startTimer().
537
538 The QTimer class provides a high-level programming interface that
539 uses signals instead of events. It also provides single-shot timers.
540
541 The event handler QObject::timerEvent() receives timer events.
542
543 \sa QTimer, QObject::timerEvent(), QObject::startTimer(),
544 QObject::killTimer()
545*/
546
547/*!
548 Constructs a timer event object with the timer identifier set to
549 \a timerId.
550*/
551QTimerEvent::QTimerEvent(int timerId)
552 : QEvent(Timer), id(timerId)
553{}
554
555/*!
556 \internal
557*/
558QTimerEvent::~QTimerEvent()
559{
560}
561
562/*!
563 \fn int QTimerEvent::timerId() const
564
565 Returns the unique timer identifier, which is the same identifier
566 as returned from QObject::startTimer().
567*/
568
569/*!
570 \class QChildEvent
571 \inmodule QtCore
572 \brief The QChildEvent class contains event parameters for child object
573 events.
574
575 \ingroup events
576
577 Child events are sent immediately to objects when children are
578 added or removed.
579
580 In both cases you can only rely on the child being a QObject (or,
581 if QObject::isWidgetType() returns \c true, a QWidget). This is
582 because in the QEvent::ChildAdded case the child is not yet fully
583 constructed; in the QEvent::ChildRemoved case it might have
584 already been destructed.
585
586 The handler for these events is QObject::childEvent().
587*/
588
589/*!
590 Constructs a child event object of a particular \a type for the
591 \a child.
592
593 \a type can be QEvent::ChildAdded, QEvent::ChildRemoved,
594 or QEvent::ChildPolished.
595
596 \sa child()
597*/
598QChildEvent::QChildEvent(Type type, QObject *child)
599 : QEvent(type), c(child)
600{}
601
602/*!
603 \internal
604*/
605QChildEvent::~QChildEvent()
606{
607}
608
609/*!
610 \fn QObject *QChildEvent::child() const
611
612 Returns the child object that was added or removed.
613*/
614
615/*!
616 \fn bool QChildEvent::added() const
617
618 Returns \c true if type() is QEvent::ChildAdded; otherwise returns
619 false.
620*/
621
622/*!
623 \fn bool QChildEvent::removed() const
624
625 Returns \c true if type() is QEvent::ChildRemoved; otherwise returns
626 false.
627*/
628
629/*!
630 \fn bool QChildEvent::polished() const
631
632 Returns \c true if type() is QEvent::ChildPolished; otherwise returns
633 false.
634*/
635
636
637/*!
638 \class QDynamicPropertyChangeEvent
639 \inmodule QtCore
640 \since 4.2
641 \brief The QDynamicPropertyChangeEvent class contains event parameters for dynamic
642 property change events.
643
644 \ingroup events
645
646 Dynamic property change events are sent to objects when properties are
647 dynamically added, changed or removed using QObject::setProperty().
648*/
649
650/*!
651 Constructs a dynamic property change event object with the property name set to
652 \a name.
653*/
654QDynamicPropertyChangeEvent::QDynamicPropertyChangeEvent(const QByteArray &name)
655 : QEvent(QEvent::DynamicPropertyChange), n(name)
656{
657}
658
659/*!
660 \internal
661*/
662QDynamicPropertyChangeEvent::~QDynamicPropertyChangeEvent()
663{
664}
665
666/*!
667 \fn QByteArray QDynamicPropertyChangeEvent::propertyName() const
668
669 Returns the name of the dynamic property that was added, changed or
670 removed.
671
672 \sa QObject::setProperty(), QObject::dynamicPropertyNames()
673*/
674
675/*!
676 Constructs a deferred delete event with an initial loopLevel() of zero.
677*/
678QDeferredDeleteEvent::QDeferredDeleteEvent()
679 : QEvent(QEvent::DeferredDelete)
680 , level(0)
681{ }
682
683/*!
684 \internal
685*/
686QDeferredDeleteEvent::~QDeferredDeleteEvent()
687{ }
688
689/*! \fn int QDeferredDeleteEvent::loopLevel() const
690
691 Returns the loop-level in which the event was posted. The
692 loop-level is set by QCoreApplication::postEvent().
693
694 \sa QObject::deleteLater()
695*/
696
697QT_END_NAMESPACE
698
699#include "moc_qcoreevent.cpp"
700