LocalMusicRepository

The LocalMusicRepository provides access to all music files on the device using Android’s MediaStore API. It handles querying, filtering, and organizing local music by tracks, albums, and artists.

This repository requires READ_EXTERNAL_STORAGE or READ_MEDIA_AUDIO permissions depending on the Android version.

Source Location: app/src/main/java/com/crowstar/deeztrackermobile/features/localmusic/LocalMusicRepository.kt

Constructor

class LocalMusicRepository(
    private val contentResolver: ContentResolver,
    private val playlistRepository: LocalPlaylistRepository? = null
)

contentResolver

ContentResolver

required

Android ContentResolver for querying MediaStore

playlistRepository

LocalPlaylistRepository?

default:"null"

Optional playlist repository for favorite track integration

Storage Methods

getTotalStorageSpace()

Get the total storage space available on the device.

return

Long

Total storage space in bytes

Example:

val repository = LocalMusicRepository(context.contentResolver)
val totalSpace = repository.getTotalStorageSpace()
val totalGB = totalSpace / (1024 * 1024 * 1024)

Track Query Methods

getAllTracks()

Get all music tracks from device storage, sorted alphabetically by title.

return

List<LocalTrack>

List of all music tracks on the device

Query Details:

Filters out non-music files (notifications, ringtones, alarms)
Sorts by title (case-insensitive)
Includes full metadata (title, artist, album, duration, file path, size, MIME type, dates)
Generates album art URIs

Example:

val tracks = repository.getAllTracks()
println("Found ${tracks.size} tracks")

tracks.forEach { track ->
    println("${track.title} by ${track.artist}")
}

getTracksForAlbum()

Get all tracks for a specific album.

albumId

Long

required

MediaStore album ID

return

List<LocalTrack>

List of tracks in the album, sorted by track number

Example:

val albumTracks = repository.getTracksForAlbum(albumId = 123L)

getTracksForArtist()

Get all tracks by a specific artist.

artistName

String

required

Artist name to filter by

return

List<LocalTrack>

List of tracks by the artist

Example:

val artistTracks = repository.getTracksForArtist("Queen")

searchTracks()

Search tracks by query string (searches title, artist, and album fields).

query

String

required

Search query string

return

List<LocalTrack>

List of tracks matching the search query

Example:

val results = repository.searchTracks("Bohemian")
// Returns tracks with "Bohemian" in title, artist, or album

getDownloadedTracks()

Get tracks from specific file paths (used to find downloaded tracks).

downloadPaths

List<String>

required

List of file paths to query

return

List<LocalTrack>

List of tracks at the specified paths

Example:

val downloadedPaths = listOf(
    "/storage/emulated/0/Music/track1.mp3",
    "/storage/emulated/0/Music/track2.flac"
)
val tracks = repository.getDownloadedTracks(downloadedPaths)

getTrackIdByPath()

Get the MediaStore ID for a track at a specific file path.

path

String

required

File path of the track

return

Long?

MediaStore track ID, or null if not found

Album Methods

getAllAlbums()

Get all albums from device storage.

return

List<LocalAlbum>

List of all albums with metadata (title, artist, track count, first year)

Album Structure:

data class LocalAlbum(
    val id: Long,
    val name: String,
    val artist: String,
    val albumArtUri: String?,
    val trackCount: Int,
    val firstYear: Int?
)

Artist Methods

getAllArtists()

Get all artists from device storage.

return

List<LocalArtist>

List of all artists with track and album counts

Artist Structure:

data class LocalArtist(
    val id: Long,
    val name: String,
    val trackCount: Int,
    val albumCount: Int,
    val albumArtUri: String? // Art from first album
)

Deletion Methods

requestDeleteTrack()

Request permission to delete a track (Android 11+).

trackId

Long

required

MediaStore track ID to delete

return

IntentSender?

IntentSender for requesting deletion permission, or null on Android 10 and below

On Android 11+, this method returns an IntentSender that must be used with startIntentSenderForResult() to request user permission for deletion.

Example:

val intentSender = repository.requestDeleteTrack(trackId = 123L)
if (intentSender != null) {
    // Android 11+ - request permission
    startIntentSenderForResult(
        intentSender,
        DELETE_REQUEST_CODE,
        null, 0, 0, 0
    )
} else {
    // Android 10 and below - direct deletion
    repository.onTrackDeleted(trackId)
}

onTrackDeleted()

Update internal state after a track has been deleted.

trackId

Long

required

MediaStore track ID that was deleted

This method removes the track from any playlists via LocalPlaylistRepository.

MediaStore Integration

The repository queries the following MediaStore columns:

_ID - Unique track identifier
TITLE - Track title
ARTIST - Artist name
ALBUM - Album name
ALBUM_ID - Album identifier (for album art)
DURATION - Track duration in milliseconds
DATA - File path
SIZE - File size in bytes
MIME_TYPE - Audio format (audio/mpeg, audio/flac, etc.)
DATE_ADDED - Unix timestamp when added
DATE_MODIFIED - Unix timestamp of last modification
TRACK - Track number in album
YEAR - Release year

Album Art Handling

Album art is retrieved using the album ID:

private fun getAlbumArtUri(albumId: Long): String? {
    val artUri = Uri.parse("content://media/external/audio/albumart")
    return ContentUris.withAppendedId(artUri, albumId).toString()
}

Usage Example

LocalMusicScreen.kt:45-68

val repository = LocalMusicRepository(
    contentResolver = context.contentResolver,
    playlistRepository = LocalPlaylistRepository(context)
)

// Get all tracks
val allTracks = repository.getAllTracks()

// Get albums
val albums = repository.getAllAlbums()

// Search
val searchResults = repository.searchTracks("Queen")

// Get storage info
val totalSpace = repository.getTotalStorageSpace()
val totalGB = totalSpace / (1024 * 1024 * 1024)

Local Library Feature

How local music browsing works in the app

LocalTrack Model

LocalTrack data structure

LocalPlaylistRepository

Playlist management

Core Services

Data Models

UI Components

Constructor

Storage Methods

getTotalStorageSpace()

Track Query Methods

getAllTracks()

getTracksForAlbum()

getTracksForArtist()

searchTracks()

getDownloadedTracks()

getTrackIdByPath()

Album Methods

getAllAlbums()

Artist Methods

getAllArtists()

Deletion Methods

requestDeleteTrack()

onTrackDeleted()

MediaStore Integration

Album Art Handling

Usage Example

See Also

Local Library Feature

LocalTrack Model

LocalPlaylistRepository

Build docs developers (and LLMs) love

Core Services

Data Models

UI Components

​Constructor

​Storage Methods

​getTotalStorageSpace()

​Track Query Methods

​getAllTracks()

​getTracksForAlbum()

​getTracksForArtist()

​searchTracks()

​getDownloadedTracks()

​getTrackIdByPath()

​Album Methods

​getAllAlbums()

​Artist Methods

​getAllArtists()

​Deletion Methods

​requestDeleteTrack()

​onTrackDeleted()

​MediaStore Integration

​Album Art Handling

​Usage Example

​See Also

Local Library Feature

LocalTrack Model

LocalPlaylistRepository

Build docs developers (and LLMs) love

Constructor

Storage Methods

getTotalStorageSpace()

Track Query Methods

getAllTracks()

getTracksForAlbum()

getTracksForArtist()

searchTracks()

getDownloadedTracks()

getTrackIdByPath()

Album Methods

getAllAlbums()

Artist Methods

getAllArtists()

Deletion Methods

requestDeleteTrack()

onTrackDeleted()

MediaStore Integration

Album Art Handling

Usage Example

See Also