class HPS::Event

The Event class is the common base class of all events. An event can be an error, input event, or a custom event. Events occur asynchronously and are processed in order from an event queue.

Subclassed by HPS::AnnotationOperator::AnnotationInsertedEvent, HPS::CameraChangedEvent, HPS::CanvasDeletedEvent, HPS::CaptureActivationEvent, HPS::ComponentHiddenEvent, HPS::ComponentHighlightEvent, HPS::ComponentIsolatedEvent, HPS::ComponentResetEvent, HPS::ComponentShownEvent, HPS::ErrorEvent, HPS::Exchange::CommonMeasurementOperator::MeasurementDeletedEvent, HPS::Exchange::CommonMeasurementOperator::MeasurementInsertedEvent, HPS::FilterActivationEvent, HPS::FocusLostEvent, HPS::HCA::RequestIdEvent, HPS::HandlesOperator::GeometryTransformedEvent, HPS::HideKeyboardEvent, HPS::HighlightEvent, HPS::ImportStatusEvent, HPS::InformationEvent, HPS::InputEvent, HPS::LayoutDeletedEvent, HPS::LayoutDetachedEvent, HPS::MarkupOperator::MarkupInsertedEvent, HPS::MeasurementOperator::MeasurementEvent, HPS::ModelDeletedEvent, HPS::ModelDetachedEvent, HPS::ShowKeyboardEvent, HPS::SmoothTransitionCompleteEvent, HPS::StandAloneWindowEvent, HPS::Stream::ExportStartedEvent, HPS::Stream::ImportCompletedEvent, HPS::TextInputEvent, HPS::TimerTickEvent, HPS::UpdateCompletedEvent, HPS::ViewDeletedEvent, HPS::ViewDetachedEvent, HPS::WarningEvent

Public Types

enum Status

Event Status - returned from a notifier to give the status of the event.


enumerator InProgress

Event is still in progress.

enumerator Completed

Event has completed.

enumerator Failed

Event failed.

Public Functions

virtual Event *Clone() const = 0

This function is used to copy custom events classes. Users that create custom event classes must override this function to provide the proper copying behavior.

inline virtual bool Drop(Event const *in_that_event) const

This optional function is used to determine if the current event can be dropped based on the following event in the queue.

inline Event(intptr_t in_channel = 0)

A constructor for generating events from built-in or custom event ID’s.

inline virtual intptr_t Freshen() const

This optional function is used to determine if the current event can be dropped in favor of newer event of the same type if one is available.


A cookie representing the freshen category. Zero indicates a non-freshening event.

inline intptr_t GetChannel() const

Returns the channel ID assigned to an event.

intptr_t GetClassID() const

Returns a unique identifier that is shared by all objects of the same class.

inline Time GetTimeStamp() const

Returns the time an event was injected into the event queue.

inline bool IsConsumable() const

Indicates whether an event will be consumed when it is handled or passed on to the next handler anyway.

virtual ~Event()

Public Static Functions

static inline void operator delete(void *in_ptr, size_t in_size)
static inline void *operator new(size_t in_size)


friend class HPSI::EventDispatcherImpl