metaData in the Audio API returns "undefined"

[XiaoGuo, Liu]

I just tried the metaData property in the Audio API at:

https://developer.ubuntu.com/api/apps/qml/sdk-15.04.4/QtMultimedia.Audio/#metaData.albumTitle-prop

All of the properties for the metaData returns "undefined":

qml: The properties of metaData is:
qml: objectName: objectName :
qml: title: title : undefined
qml: subTitle: subTitle : undefined
qml: author: author : undefined
qml: comment: comment : undefined
qml: description: description : undefined
qml: category: category : undefined
qml: genre: genre : undefined
qml: year: year : undefined
qml: date: date : undefined
qml: userRating: userRating : undefined
qml: keywords: keywords : undefined
qml: language: language : undefined
qml: publisher: publisher : undefined
qml: copyright: copyright : undefined
qml: parentalRating: parentalRating : undefined
qml: ratingOrganization: ratingOrganization : undefined
qml: size: size : undefined
qml: mediaType: mediaType : undefined
qml: duration: duration : undefined
qml: audioBitRate: audioBitRate : undefined
qml: audioCodec: audioCodec : undefined
qml: averageLevel: averageLevel : undefined
qml: channelCount: channelCount : undefined
qml: peakValue: peakValue : undefined
qml: sampleRate: sampleRate : undefined
qml: albumTitle: albumTitle : undefined
qml: albumArtist: albumArtist : undefined
qml: contributingArtist: contributingArtist : undefined
qml: composer: composer : undefined
qml: conductor: conductor : undefined
qml: lyrics: lyrics : undefined
qml: mood: mood : undefined
qml: trackNumber: trackNumber : undefined
qml: trackCount: trackCount : undefined
qml: coverArtUrlSmall: coverArtUrlSmall : undefined
qml: coverArtUrlLarge: coverArtUrlLarge : undefined
qml: resolution: resolution : undefined
qml: pixelAspectRatio: pixelAspectRatio : undefined
qml: videoFrameRate: videoFrameRate : undefined
qml: videoBitRate: videoBitRate : undefined
qml: videoCodec: videoCodec : undefined
qml: posterUrl: posterUrl : undefined
qml: chapterNumber: chapterNumber : undefined
qml: director: director : undefined
qml: leadPerformer: leadPerformer : undefined
qml: writer: writer : undefined
qml: cameraManufacturer: cameraManufacturer : undefined
qml: cameraModel: cameraModel : undefined
qml: event: event : undefined
qml: subject: subject : undefined
qml: orientation: orientation : undefined
qml: exposureTime: exposureTime : undefined
qml: fNumber: fNumber : undefined
qml: exposureProgram: exposureProgram : undefined
qml: isoSpeedRatings: isoSpeedRatings : undefined
qml: exposureBiasValue: exposureBiasValue : undefined
qml: dateTimeOriginal: dateTimeOriginal : undefined
qml: dateTimeDigitized: dateTimeDigitized : undefined
qml: subjectDistance: subjectDistance : undefined
qml: meteringMode: meteringMode : undefined
qml: lightSource: lightSource : undefined
qml: flash: flash : undefined
qml: focalLength: focalLength : undefined
qml: exposureMode: exposureMode : undefined
qml: whiteBalance: whiteBalance : undefined
qml: digitalZoomRatio: digitalZoomRatio : undefined
qml: focalLengthIn35mmFilm: focalLengthIn35mmFilm : undefined
qml: sceneCaptureType: sceneCaptureType : undefined
qml: gainControl: gainControl : undefined
qml: contrast: contrast : undefined
qml: saturation: saturation : undefined
qml: sharpness: sharpness : undefined
qml: deviceSettingDescription: deviceSettingDescription : undefined
qml: gpsLatitude: gpsLatitude : undefined
qml: gpsLongitude: gpsLongitude : undefined
qml: gpsAltitude: gpsAltitude : undefined
qml: gpsTimeStamp: gpsTimeStamp : undefined
qml: gpsSatellites: gpsSatellites : undefined
qml: gpsStatus: gpsStatus : undefined
qml: gpsDOP: gpsDOP : undefined
qml: gpsSpeed: gpsSpeed : undefined
qml: gpsTrack: gpsTrack : undefined
qml: gpsTrackRef: gpsTrackRef : undefined
qml: gpsImgDirection: gpsImgDirection : undefined
qml: gpsImgDirectionRef: gpsImgDirectionRef : undefined
qml: gpsMapDatum: gpsMapDatum : undefined
qml: gpsProcessingMethod: gpsProcessingMethod : undefined
qml: gpsAreaInformation: gpsAreaInformation : undefined
qml: objectNameChanged: objectNameChanged : function() { [code] }
qml: metaDataChanged: metaDataChanged : function() { [code] }