Symbian
Symbian OS Library

SYMBIAN OS V9.3

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General events

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 RWindowTreeNode::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 RWindowTreeNode::EnableOnEvents() was called.

EEventPassword

None

The client handle of the RWindowGroup of the window on which RWindowBase::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 RWindowTreeNode::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.

EEventFocusGroupChanged

None

The client handle of the RWindowTreeNode on which RWindowTreeNode::EnableFocusChangeEvents() was called.

EEventCaseOpened

None

The client handle of the RWindowTreeNode on which RWindowTreeNode::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 RWindowTreeNode::EnableGroupListChangeEvents() was called.

EEventKeyRepeat

n/a (only sent to the key click plug-in interface)

n/a

EEventUser

n/a

n/a

Event types may be grouped as follows:

Certain event types are not automatically delivered to the window server session: if they are required they must be explicitly requested by a window. The window server session will then receive the events, with a handle to the window that requested them, and the handle can be used to invoke a member function of the window that requested the events. Events that must be requested in this way are of the following types:

If several windows associated with a window server session request notification of the same event, then the event is notified separately to all windows which requested it.

Events of type EEventScreenDeviceChanged are issued if the screen size mode changes. Such events are sent, for example, when the cover on a phone that supports screen flipping is opened or closed. Use RWindowGroup::EnableScreenChangeEvents() to instruct the window server to report screen change events to a window group.