MFepAttributeStorer Class Reference

#include <mw/fepbconfig.h>

Link against: fepbase.lib

class MFepAttributeStorer
Public Member Functions
pure virtual TUid AttributeAtIndex(TInt)
pure virtual TInt NumberOfAttributes()
IMPORT_C voidReadAllAttributesL(CCoeEnv &)
pure virtual voidReadAttributeDataFromStreamL(TUid, RReadStream &)
IMPORT_C voidWriteAttributeDataAndBroadcastL(CCoeEnv &, TUid)
IMPORT_C voidWriteAttributeDataAndBroadcastL(CCoeEnv &, const TArray< TUid > &)
pure virtual voidWriteAttributeDataToStreamL(TUid, RWriteStream &)

Detailed Description

Protocol for storing, restoring and synchronising FEP attributes.

An abstract base class for CCoeFep, so FEPs must implement the pure virtual functions declared in this class.

Rather than using a single device-wide instance of a FEP, each application has its own instance of the FEP. MFepAttributeStorer provides a framework for synchronising FEP attributes across each running instance of the same FEP. For this to happen, the FEP must implement MFepAttributeStorer::WriteAttributeDataToStreamL() and MFepAttributeStorer::ReadAttributeDataFromStreamL().

Attributes are FEP-specific, and are identified by a UID which can be accessed using AttributeAtIndex(). An example of a FEP attribute might be whether inline editing is enabled or disabled.

Member Function Documentation

AttributeAtIndex ( TInt )

TUid AttributeAtIndex(TIntaIndex)const [pure virtual]

Returns the UID of the FEP attribute at the index specified.

ParameterDescription
aIndexAn array index.

Returns: The UID of the FEP attribute at aIndex.

NumberOfAttributes ( )

TInt NumberOfAttributes()const [pure virtual]

Returns the total number of FEP attributes.

Returns: The number of FEP attributes.

ReadAllAttributesL ( CCoeEnv & )

IMPORT_C voidReadAllAttributesL(CCoeEnv &aConeEnvironment)

Reads all of the FEP's attributes from the system settings.

Calls the implementation of ReadAttributeDataFromStreamL() for each attribute.

This function has identical behaviour to CCoeFep::ReadAllAttributesL().

ParameterDescription
aConeEnvironmentNot used.

ReadAttributeDataFromStreamL ( TUid, RReadStream & )

voidReadAttributeDataFromStreamL(TUidaAttributeUid,
RReadStream &aStream
)[pure virtual]

Reads the value of the attribute identified by the UID specified in aAttributeUid from the specified read stream.

You should take appropriate action if the attribute has changed, e.g. if inline editing has been disabled, you might cancel the current transaction.

This function is called by MFepAttributeStorer::ReadAllAttributesL() for all attributes. It is also called when the FEP receives a message that an attribute has been changed by another running instance of the FEP (using WriteAttributeDataAndBroadcastL()).

ParameterDescription
aAttributeUidIdentifies the attribute whose value should be read.
aStreamRead stream from which to read the attribute's value.

WriteAttributeDataAndBroadcastL ( CCoeEnv &, TUid )

IMPORT_C voidWriteAttributeDataAndBroadcastL(CCoeEnv &aConeEnvironment,
TUidaAttributeUid
)

Call this function after changing the value of an attribute that needs to be synchronised.

Writes the new value to the system-wide settings and causes all other running instances of the FEP to be notified of the change.

A panic occurs if aAttributeUid is not one of the FEP's attributes.

capability
WriteDeviceData
ParameterDescription
aConeEnvironmentThe FEP's control environment.
aAttributeUidThe UID of the attribute whose value has changed.

WriteAttributeDataAndBroadcastL ( CCoeEnv &, const TArray< TUid > & )

IMPORT_C voidWriteAttributeDataAndBroadcastL(CCoeEnv &aConeEnvironment,
const TArray< TUid > &aAttributeUids
)

Call this function after changing the value of multiple attributes that need to be synchronised.

Writes the new values to the system settings, and causes all other running instances of the FEP to be notified of the change.

A panic occurs if any of the attributes contained in aAttributeUids are not among the FEP's attributes.

capability
WriteDeviceData To prevent corruption of FEP settings.
ParameterDescription
aConeEnvironmentNot used.
aAttributeUidsArray of UIDs of the attribute whose values have changed.

WriteAttributeDataToStreamL ( TUid, RWriteStream & )

voidWriteAttributeDataToStreamL(TUidaAttributeUid,
RWriteStream &aStream
)const [pure virtual]

Writes the value of the attribute specified to the specified write stream.

Called by MFepAttributeStorer::WriteAttributeDataAndBroadcastL() for each attribute passed to it.

ParameterDescription
aAttributeUidUID of the attribute to write to the stream.
aStreamThe stream to which to write the attribute.