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General events

In this context, a general event is any kind of event that is generated by the Window Server and delivered to the client, with the exception of redraw and priority key events.

Variant: ScreenPlay and non-ScreenPlay. Target audience: Application developers.

All events generated by the Window Server, except redraw events and priority key events, are delivered to the client in a TWsEvent which is requested asynchronously by the RWsSession::EventReady() function. When this request completes, it is handled by an active object CActive::RunL() function which must use RWsSession::GetEvent() to get the TWsEvent representing the event. The TWsEvent::Type() function is used to identify the event type which can then retrieve the appropriate type of data.

The following table lists for each event type returned by TWsEvent::Type(), what object TWsEvent::EventData() returns, and what the TWsEvent::Handle() represents.

TWsEvent::Type()	TWsEvent::EventData()	TWsEvent::Handle()
EEventNull	n/a	n/a
EEventKey	TKeyEvent	RWindowGroup client handle
EEventKeyUp	TKeyEvent	RWindowGroup client handle
EEventKeyDown	TKeyEvent	RWindowGroup client handle
EEventModifiersChanged	TModifiersChangedEvent	The client handle of the RWindowTreeNode on which `EnableModifierChangedEvents()` was called.
EEventPointer	TPointerEvent	RWindow client handle
EEventPointerEnter	TPointerEvent	RWindow client handle
EEventPointerExit	TPointerEvent	RWindow client handle
EEventPointerBufferReady	None - call RWindowBase::RetrievePointerMoveBuffer()	RWindow client handle
EEventDragDrop	TPointerEvent	RWindow client handle
EEventFocusLost	None	RWindowGroup client handle
EEventFocusGained	None	RWindowGroup client handle
EEventSwitchOn	None	The client handle of the RWindowTreeNode on which `EnableOnEvents()` was called.
EEventPassword	None	The client handle of the RWindowGroup of the window on which `PasswordWindow()` was called.
EEventWindowGroupsChanged	None	The client handle of the RWindowTreeNode on which RWindowTreeNode::EnableGroupChangeEvents() was called.
EEventErrorMessage	TWsErrorMessage	The client handle of the RWindowTreeNode on which `EnableErrorMessages()` was called.
EEventMessageReady	None	RWindowGroup client handle
EEventMarkInvalid	n/a	n/a
EEventSwitchOff	None	The client handle of the RWindowTreeNode passed into RWsSession::RequestOffEvents().
EEventKeySwitchOff	None	The client handle of the RWindowTreeNode passed into RWsSession::RequestOffEvents().
EEventScreenDeviceChanged	None	The client handle of the object on which RWindowGroup::EnableScreenChangeEvents() was called.
EEventDisplayChanged	TWsDisplayChangedEvent	The client handle of the CWsScreenDevice object on which MDisplayControl:: EnableDisplayChangeEvents() was called. See Display Control and Mapping in the Window Server Client for more information.
EEventFocusGroupChanged	None	The client handle of the RWindowTreeNode on which `EnableFocusChangeEvents()` was called.
EEventWindowVisibilityChanged	TWsVisibilityChangedEvent	The client handle of the RWindowTreeNode on which `EnableVisibilityChangeEvents()` was called.
EEventCaseOpened	None	The client handle of the RWindowTreeNode on which `EnableOnEvents()` was called.
EEventCaseClosed	None	The client handle of the RWindowTreeNode passed into RWsSession::RequestOffEvents().
EEventWindowGroupListChanged	None	The client handle of the RWindowTreeNode on which `EnableGroupListChangeEvents()` was called.
EEventKeyRepeat	n/a (only sent to the key click plug-in interface)	n/a
EEventUser	n/a	n/a

Parent topic: Window Server Client-Side Events

Related concepts

Pointer Handling

Declaring a Window Server Event-Handling Class

Handling General Events

Processing Window-Group Events

Processing Window Events

Processing System Events