Class MEikSrvNotifierBase2

class MEikSrvNotifierBase2;

Description

Interface to a plug-in server side notifier.

Any number of MEikSrvNotifierBase2 objects can be included in a single DLL. All notifiers are loaded during device startup and are not destroyed until the Uikon server closes down.

All notifiers run in the uikon server thread so are able to directly access server side status panes but cannot call any functions on REikAppUiSession.

Members

Defined in MEikSrvNotifierBase2:

• Cancel()Cancels an active notifier.
• ENotifierPriorityAbsoluteThe highest priority value.
• ENotifierPriorityHighThe third highest priority value.
• ENotifierPriorityLowThe fourth highest priority value.
• ENotifierPriorityLowestThe lowest priority value.
• ENotifierPriorityVHighThe second highest priority value.
• ENotifierPriorityVLowThe fifth highest priority value.
• HandleSystemEventL(TUid)Handles a screen change event.
• Info()constGets the notifier parameters.
• MEikSrvNotifierBase2()
• MEikSrvNotifierBase2_Reserved_2()Reserved for future use
• NotifierCapabilites()Gets notifier capabilities.
• RegisterL()Performs any initialisation that this notifier may require.
• Release()Frees all resources owned by this notifier.
• StartL(const TDesC8 &)Starts the notifier.
• StartL(const TDesC8 &,TInt,const RMessagePtr2 &)Starts the notifier.
• TNotifierInfoContains the notifier parameters.
• TNotifierPriorityDefines a set of notifier priorities. The use and application of these values is...
• UpdateL(const TDesC8 &)Updates a currently active notifier with new data.
• UpdateL(const TDesC8 &,TInt,const RMessagePtr2 &)Updates a currently active notifier with new data.
• iManager
• ~MEikSrvNotifierBase2()

IMPORT_C MEikSrvNotifierBase2();

Description

IMPORT_C virtual ~MEikSrvNotifierBase2();

Description

virtual void Release()=0;

Description

Frees all resources owned by this notifier.

This function is called by the notifier framework when all resources allocated by notifiers should be freed. As a minimum, this function should delete this object (i.e. delete this;).

Note that it is important to implement this function correctly to avoid memory leaks.

virtual TNotifierInfo RegisterL()=0;

Description

Performs any initialisation that this notifier may require.

The function is called when the notifier is loaded (when the plug-in DLL is loaded). It is called only once.

As a minimum, the function should return a MEikSrvNotifierBase2::TNotifierInfo instance describing the notifier parameters. A good implementation would be to set this into a data member, and then to return it. This is because the same information is returned by MEikSrvNotifierBase2::Info()const.

The function is safe to leave from, so it is possible, although rarely necessary, to allocate objects as you would normally do in a ConstructL() function as part of two-phase construction.

Return value

MEikSrvNotifierBase2::TNotifierInfo Describes the parameters of the notifier.

virtual TNotifierInfo Info() const=0;

Description

Gets the notifier parameters.

This is usually the same information as returned by MEikSrvNotifierBase2::RegisterL() but can be varied at run time.

Return value

MEikSrvNotifierBase2::TNotifierInfo Describes the parameters of the notifier.

virtual TPtrC8 StartL(const TDesC8 &aBuffer)=0;

Description

Starts the notifier.

This is called as a result of a client-side call to RNotifier::StartNotifier(TUid,const TDesC8 &), which the client uses to start a notifier from which it does not expect a response.

The function is synchronous, but it should be implemented so that it completes as soon as possible, allowing the notifier framework to enforce its priority mechanism.

It is not possible to to wait for a notifier to complete before returning from this function unless the notifier is likely to finish implementing its functionality immediately.

Parameters

const TDesC8 &aBuffer Data that can be passed from the client-side. The format and meaning of any data is implementation dependent.

Return value

TPtrC8 A pointer descriptor representing data that may be returned. The format and meaning of any data is implementation dependent.

virtual void StartL(const TDesC8 &aBuffer, TInt aReplySlot, const RMessagePtr2 &aMessage)=0;

Description

Starts the notifier.

This is called as a result of a client-side call to the asynchronous function RNotifier::StartNotifierAndGetResponse(TRequestStatus &,TUid,const TDesC8 &,TDes8 &). This means that the client is waiting, asynchronously, for the notifier to tell the client that it has finished its work.

It is important to return from this function as soon as possible, and derived classes may find it useful to take a copy of the reply-slot number and the RMessage object.

The implementation of a derived class must make sure that Complete() is called on the RMessage object when the notifier is deactivated.

This function may be called multiple times if more than one client starts the notifier.

Parameters

const TDesC8 &aBuffer Data that can be passed from the client-side. The format and meaning of any data is implementation dependent. TInt aReplySlot Identifies which message argument to use for the reply. This message argument will refer to a modifiable descriptor, a TDes8 type, into which data can be returned. The format and meaning of any returned data is implementation dependent. const RMessagePtr2 &aMessage Encapsulates a client request.

virtual void Cancel()=0;

Description

Cancels an active notifier.

This is called as a result of a client-side call to RNotifier::CancelNotifier(TUid).

An implementation should free any relevant resources and complete any outstanding messages, if relevant.

virtual TPtrC8 UpdateL(const TDesC8 &aBuffer)=0;

Description

Updates a currently active notifier with new data.

This is called as a result of a client-side call to RNotifier::UpdateNotifier(TUid,const TDesC8 &,TDes8 &).

Parameters

const TDesC8 &aBuffer Data that can be passed from the client-side. The format and meaning of any data is implementation dependent.

Return value

TPtrC8 A pointer descriptor representing data that may be returned. The format and meaning of any data is implementation dependent.

IMPORT_C virtual void UpdateL(const TDesC8 &aBuffer, TInt aReplySlot, const RMessagePtr2 &aMessage);

Description

Updates a currently active notifier with new data.

This is called as a result of a client-side call to the asynchronous function RNotifier::UpdateNotifierAndGetResponse(TRequestStatus &,TUid,const TDesC8 &,TDes8 &). This means that the client is waiting, asynchronously, for the notifier to tell the client that it has finished its work.

It is important to return from this function as soon as possible, and derived classes may find it useful to take a copy of the reply-slot number and the RMessage object.

The implementation of a derived class must make sure that Complete() is called on the RMessage object when the notifier is deactivated.

This function may be called multiple times if more than one client updates the notifier.

Parameters

const TDesC8 &aBuffer Data that can be passed from the client-side. The format and meaning of any data is implementation dependent. TInt aReplySlot Identifies which message argument to use for the reply. This message argument will refer to a modifiable descriptor, a TDes8 type, into which data can be returned. The format and meaning of any returned data is implementation dependent. const RMessagePtr2 &aMessage Encapsulates a client request.

private: IMPORT_C virtual void MEikSrvNotifierBase2_Reserved_2();

Description

Reserved for future use

IMPORT_C virtual void HandleSystemEventL(TUid aEvent);

Description

Handles a screen change event.

This function is called by the notifier manager, but only if the notifier can handle a change to the screen device, i.e. if a call to MEikSrvNotifierBase2::NotifierCapabilites() reports that the EScreenDeviceChangeSupported flag is set.

The default implementation is empty.

Parameters

TUid aEvent The Uid representing the event.

IMPORT_C virtual TInt NotifierCapabilites();

Description

Gets notifier capabilities.

Calls the LAF implemented function.

Return value

TInt

class TNotifierInfo;

Description

Contains the notifier parameters.

Members

Defined in MEikSrvNotifierBase2::TNotifierInfo:

• iChannelThe Uid that identifies the channel to be used by the notifier (e.g. the screen,...
• iPriorityThe notifier priority, typically chosen from the standard set.
• iUidThe Uid that identifies the notifier.

See also:

• MEikSrvNotifierBase2::TNotifierPriorityDefines a set of notifier priorities. The use and application of these values is...

Member data

---

iUid

TUid iUid;

Description

The Uid that identifies the notifier.

---

iChannel

TUid iChannel;

Description

The Uid that identifies the channel to be used by the notifier (e.g. the screen, an LED etc)

---

iPriority

TInt iPriority;

Description

The notifier priority, typically chosen from the standard set.

See also:

• MEikSrvNotifierBase2::TNotifierPriorityDefines a set of notifier priorities. The use and application of these values is...

TNotifierPriority

Description

Defines a set of notifier priorities. The use and application of these values is implementation-dependent.

ENotifierPriorityAbsolute The highest priority value. ENotifierPriorityVHigh The second highest priority value. ENotifierPriorityHigh The third highest priority value. ENotifierPriorityLow The fourth highest priority value. ENotifierPriorityVLow The fifth highest priority value. ENotifierPriorityLowest The lowest priority value.

protected: MEikSrvNotifierManager * iManager;

Description