PreloadMediaSource

@UnstableApi
class PreloadMediaSource : WrappingMediaSource

kotlin.Any
   ↳ androidx.media3.exoplayer.source.BaseMediaSource
     ↳ androidx.media3.exoplayer.source.CompositeMediaSource
       ↳ androidx.media3.exoplayer.source.WrappingMediaSource
         ↳ androidx.media3.exoplayer.source.preload.PreloadMediaSource

Preloads a MediaSource and provides a MediaPeriod that has data loaded before playback.

Summary

Nested types

Factory for PreloadMediaSource.

Controls preloading of PreloadMediaSource.

Public functions
PreloadMediaPeriod!
createPeriod(
    id: MediaSource.MediaPeriodId!,
    allocator: Allocator!,
    startPositionUs: Long
)

Creates the requested MediaPeriod.
Unit
preload(startPositionUs: Long)

Preloads the PreloadMediaSource for an expected start position startPositionUs.
Unit
releasePeriod(mediaPeriod: MediaPeriod!)

Releases a MediaPeriod.
Unit

Releases the preloaded resources in PreloadMediaSource.

Protected functions
MediaSource.MediaPeriodId!

Returns the MediaPeriodId in the wrapping source corresponding to the specified in a child source.
Unit

Called when the child source info has been refreshed.
Unit

Starts source preparation and enables the source, see prepareSource.
Unit

Releases the source, see releaseSource.

Inherited functions
From androidx.media3.exoplayer.source.BaseMediaSource
Unit
addDrmEventListener(
    handler: Handler!,
    eventListener: DrmSessionEventListener!
)

Adds a DrmSessionEventListener to the list of listeners which are notified of DRM events for this media source.
Unit
addEventListener(
    handler: Handler!,
    eventListener: MediaSourceEventListener!
)

Adds a MediaSourceEventListener to the list of listeners which are notified of media source events.
DrmSessionEventListener.EventDispatcher!

Returns a DrmSessionEventListener.EventDispatcher which dispatches all events to the registered listeners with the specified MediaPeriodId
DrmSessionEventListener.EventDispatcher!
createDrmEventDispatcher(
    windowIndex: Int,
    mediaPeriodId: MediaSource.MediaPeriodId?
)

Returns a DrmSessionEventListener.EventDispatcher which dispatches all events to the registered listeners with the specified window index and MediaPeriodId.
MediaSourceEventListener.EventDispatcher!

Returns a MediaSourceEventListener.EventDispatcher which dispatches all events to the registered listeners with the specified MediaPeriodId.
MediaSourceEventListener.EventDispatcher!
createEventDispatcher(
    mediaPeriodId: MediaSource.MediaPeriodId!,
    mediaTimeOffsetMs: Long
)

This function is deprecated.

Use createEventDispatcher instead.
MediaSourceEventListener.EventDispatcher!
createEventDispatcher(
    windowIndex: Int,
    mediaPeriodId: MediaSource.MediaPeriodId?
)

Returns a MediaSourceEventListener.EventDispatcher which dispatches all events to the registered listeners with the specified window index and MediaPeriodId.
MediaSourceEventListener.EventDispatcher!
createEventDispatcher(
    windowIndex: Int,
    mediaPeriodId: MediaSource.MediaPeriodId?,
    mediaTimeOffsetMs: Long
)

This function is deprecated.

Use createEventDispatcher instead.
Unit

Disables the source for the creation of MediaPeriods.
Unit

Enables the source for the creation of MediaPeriods.
Boolean

Returns whether the source is enabled.
Unit
prepareSource(
    caller: MediaSource.MediaSourceCaller!,
    mediaTransferListener: TransferListener?
)

This function is deprecated.

Implement prepareSource instead.
Unit
prepareSource(
    caller: MediaSource.MediaSourceCaller!,
    mediaTransferListener: TransferListener?,
    playerId: PlayerId!
)

Registers a MediaSourceCaller.
Boolean

Returns whether the source has prepareSource called.
Unit

Updates timeline and manifest and notifies all listeners of the update.
Unit

Unregisters a caller, and disables and releases the source if no longer required.
Unit

Removes a DrmSessionEventListener from the list of listeners which are notified of DRM events for this media source.
Unit

Removes a MediaSourceEventListener from the list of listeners which are notified of media source events.
From androidx.media3.exoplayer.source.CompositeMediaSource
Unit

Disables a child source.
Unit

Disables the source, see disable.
Unit

Enables a child source.
Unit

Enables the source, see enable.
MediaSource.MediaPeriodId?
getMediaPeriodIdForChildMediaPeriodId(
    @UnknownNull childSourceId: T!,
    mediaPeriodId: MediaSource.MediaPeriodId!
)

Returns the MediaPeriodId in the composite source corresponding to the specified in a child source.
Long
getMediaTimeForChildMediaTime(
    @UnknownNull childSourceId: T!,
    mediaTimeMs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId?
)

Returns the media time in the MediaPeriod of the composite source corresponding to the specified media time in the MediaPeriod of the child source.
Int
getWindowIndexForChildWindowIndex(
    @UnknownNull childSourceId: T!,
    windowIndex: Int
)

Returns the window index in the composite source corresponding to the specified window index in a child source.
Unit

Throws any pending error encountered while loading or refreshing source information.
abstract Unit
onChildSourceInfoRefreshed(
    @UnknownNull childSourceId: T!,
    mediaSource: MediaSource!,
    newTimeline: Timeline!
)

Called when the source info of a child source has been refreshed.
Unit
prepareChildSource(@UnknownNull id: T!, mediaSource: MediaSource!)

Prepares a child source.
Unit

Releases a child source.
From androidx.media3.exoplayer.source.WrappingMediaSource
Boolean

Returns whether the for this source can be updated with the provided item.
Unit

Disables the child source.
Unit

Enables the child source.
Timeline?

Returns the initial placeholder timeline that is returned immediately when the real timeline is not yet known, or null to let the player create an initial timeline.
MediaItem!

Returns the whose media is provided by the source.
MediaSource.MediaPeriodId?
getMediaPeriodIdForChildMediaPeriodId(
    childSourceId: Void!,
    mediaPeriodId: MediaSource.MediaPeriodId!
)

Returns the MediaPeriodId in the composite source corresponding to the specified in a child source.
Long
getMediaTimeForChildMediaTime(
    mediaTimeMs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId?
)

Returns the media time in the MediaPeriod of the wrapping source corresponding to the specified media time in the MediaPeriod of the child source.
Long
getMediaTimeForChildMediaTime(
    childSourceId: Void!,
    mediaTimeMs: Long,
    mediaPeriodId: MediaSource.MediaPeriodId?
)

Returns the media time in the MediaPeriod of the composite source corresponding to the specified media time in the MediaPeriod of the child source.
Int

Returns the window index in the wrapping source corresponding to the specified window index in a child source.
Int
getWindowIndexForChildWindowIndex(childSourceId: Void!, windowIndex: Int)

Returns the window index in the composite source corresponding to the specified window index in a child source.
Boolean

Returns true if the media source is guaranteed to never have zero or more than one window.
Unit
onChildSourceInfoRefreshed(
    childSourceId: Void!,
    mediaSource: MediaSource!,
    newTimeline: Timeline!
)

Called when the source info of a child source has been refreshed.
Unit

Prepares the wrapped child source.
Unit
prepareSourceInternal(mediaTransferListener: TransferListener?)

Starts source preparation and enables the source, see prepareSource.
Unit

Releases the child source.
Unit

Updates the for this source.

Inherited properties
From androidx.media3.exoplayer.source.BaseMediaSource
PlayerId?
From androidx.media3.exoplayer.source.WrappingMediaSource
MediaSource!

The wrapped child MediaSource.

Public functions

createPeriod

fun createPeriod(
    id: MediaSource.MediaPeriodId!,
    allocator: Allocator!,
    startPositionUs: Long
): PreloadMediaPeriod!

Creates the requested MediaPeriod.

This method typically forwards to the wrapped media source and optionally wraps the returned MediaPeriod.

See also
createPeriod

preload

fun preload(startPositionUs: Long): Unit

Preloads the PreloadMediaSource for an expected start position startPositionUs.

Can be called from any thread.

Parameters
startPositionUs: Long

The expected starting position in microseconds, or TIME_UNSET to indicate the default start position.

releasePeriod

fun releasePeriod(mediaPeriod: MediaPeriod!): Unit

Releases a MediaPeriod.

This method typically forwards to the wrapped media source and optionally unwraps the provided MediaPeriod.

See also
releasePeriod

releasePreloadMediaSource

fun releasePreloadMediaSource(): Unit

Releases the preloaded resources in PreloadMediaSource.

Can be called from any thread.

Protected functions

getMediaPeriodIdForChildMediaPeriodId

protected fun getMediaPeriodIdForChildMediaPeriodId(
    mediaPeriodId: MediaSource.MediaPeriodId!
): MediaSource.MediaPeriodId!

Returns the MediaPeriodId in the wrapping source corresponding to the specified in a child source. The default implementation does not change the media period id.

Parameters
mediaPeriodId: MediaSource.MediaPeriodId!

A MediaPeriodId of the child source.
Returns
MediaSource.MediaPeriodId!

The corresponding MediaPeriodId in the wrapping source. Null if no corresponding media period id can be determined.

onChildSourceInfoRefreshed

protected fun onChildSourceInfoRefreshed(newTimeline: Timeline!): Unit

Called when the child source info has been refreshed.

This Timeline can be amended if needed, for example using . The Timeline for the wrapping source needs to be published with refreshSourceInfo.

Parameters
newTimeline: Timeline!

The timeline of the child source.

prepareSourceInternal

protected fun prepareSourceInternal(): Unit

Starts source preparation and enables the source, see prepareSource. This method is called at most once until the next call to releaseSourceInternal.

releaseSourceInternal

protected fun releaseSourceInternal(): Unit

Releases the source, see releaseSource. This method is called exactly once after each call to prepareSourceInternal.