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SYMBIAN OS V9.4

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#include <midiclientutility.h>

Class MMidiClientUtilityObserver

class MMidiClientUtilityObserver;

Description

Active object utility class to allow MIDI events to be signalled asynchronously.

Members

Defined in MMidiClientUtilityObserver:

See also:


Member functions


MmcuoStateChanged(TMidiState,TMidiState,const TTimeIntervalMicroSeconds &,TInt)

virtual void MmcuoStateChanged(TMidiState aOldState, TMidiState aNewState, const TTimeIntervalMicroSeconds &aTime, TInt aError)=0;

Description

A state change has occurred in the MIDI client utility.

Parameters

TMidiState aOldState

Old state.

TMidiState aNewState

New state.

const TTimeIntervalMicroSeconds &aTime

The time in microseconds at which playback stopped relative to the start of the MIDI resource.

TInt aError

Error code.


MmcuoTempoChanged(TInt)

virtual void MmcuoTempoChanged(TInt aMicroBeatsPerMinute)=0;

Description

The MIDI resource has encountered a tempo change message in the MIDI data stream.

Parameters

TInt aMicroBeatsPerMinute

New tempo value in micro beats per minute (BPM*1000000).


MmcuoVolumeChanged(TInt,TReal32)

virtual void MmcuoVolumeChanged(TInt aChannel, TReal32 aVolumeInDecibels)=0;

Description

The MIDI resource has encountered a volume change message in the MIDI data stream.

Parameters

TInt aChannel

Logical channel to which the message applies. 0 <= aChannel < ChannelsSupportedL().

TReal32 aVolumeInDecibels

New volume setting being used.


MmcuoMuteChanged(TInt,TBool)

virtual void MmcuoMuteChanged(TInt aChannel, TBool aMuted)=0;

Description

The MIDI resource has encountered a mute message in the MIDI data stream.

Parameters

TInt aChannel

Logical channel to which the message applies. 0 <= aChannel < ChannelsSupportedL().

TBool aMuted

New muting state of the channel - ETrue is muted, EFalse is unmuted.


MmcuoSyncUpdate(const TTimeIntervalMicroSeconds &,TInt64)

virtual void MmcuoSyncUpdate(const TTimeIntervalMicroSeconds &aMicroSeconds, TInt64 aMicroBeats)=0;

Description

Callback in response to a call to CMIDIClientUtility::SetSyncUpdateCallbackIntervalL(). By default there are no callbacks. Otherwise the callback is called at an interval set by the client.

Parameters

const TTimeIntervalMicroSeconds &aMicroSeconds

Position in microseconds relative to the start of the resource - only set if the sync update set function was called with the microseconds parameter set.

TInt64 aMicroBeats

Position in microbeats relative to the start of the resource - only set if the sync update set function was called with the microbeats parameter set and the microseconds parameter set to 0.


MmcuoMetaDataEntryFound(const TInt,const TTimeIntervalMicroSeconds &)

virtual void MmcuoMetaDataEntryFound(const TInt aMetaDataEntryId, const TTimeIntervalMicroSeconds &aPosition)=0;

Description

A timed meta data entry has been found in the MIDI data stream, eg a timed song lyric in an SMF file.

Parameters

const TInt aMetaDataEntryId

Index of the meta data entry - if this entry has not been encountere before, it will be added to the list of meta data entries. Previously encountered timed entries still generate this callback.

const TTimeIntervalMicroSeconds &aPosition

Position in microseconds relative to the start of the MIDI resource that the MIDI meta data entry was found at.


MmcuoMipMessageReceived(const RArray< TMipMessageEntry > &)

virtual void MmcuoMipMessageReceived(const RArray< TMipMessageEntry > &aMessage)=0;

Description

A MIP message has been found in the MIDI data stream.

Parameters

const RArray< TMipMessageEntry > &aMessage

Reference to an array of MIP message entries (logical {channel, MIP} value pairs) contained in the message.


MmcuoPolyphonyChanged(TInt)

virtual void MmcuoPolyphonyChanged(TInt aNewPolyphony)=0;

Description

The polyphony of the MIDI engine has changed.

Parameters

TInt aNewPolyphony

The new polyphony value.


MmcuoInstrumentChanged(TInt,TInt,TInt)

virtual void MmcuoInstrumentChanged(TInt aChannel, TInt aBankId, TInt aInstrumentId)=0;

Description

An instrument has been changed on a channel.

Parameters

TInt aChannel

Channel where the change of instrument occurred. 0 <= aChannel < ChannelsSupportedL().

TInt aBankId

Identifier of the bank that the instrument belongs to, occupying no more than 14 bits. The bank ID is a concatenation of MIDI bank MSB and LSB values.

TInt aInstrumentId

Identifier of the instrument that has been changed. 0 <= aInstrumentId <= 127.