PresentationState

Artifact: androidx.media3:media3-ui-compose

@UnstableApi
class PresentationState

State that holds information to correctly deal with UI components related to the rendering of frames to a surface.

Summary

Public constructors
`PresentationState(keepContentOnReset: Boolean)`

Public functions
`suspend Unit`	`observe(player: Player?)` Subscribes to updates from `Player.Events` and listens to

Public properties
`Boolean`	`coverSurface` set to false when the Player emits `Player.EVENT_RENDERED_FIRST_FRAME` and reset back to true on `Player.EVENT_TRACKS_CHANGED` depending on the number and type of tracks.
`Boolean`	`keepContentOnReset`
`Player?`	`@VisibleForTesting(otherwise = 2) player`
`Size?`	`videoSizeDp` wraps `Player.getVideoSize` in Compose's `Size`, becomes `null` when either height or width of the video is zero.

Public constructors

PresentationState

PresentationState(keepContentOnReset: Boolean = false)

Parameters
`keepContentOnReset: Boolean = false`	whether the currently displayed video frame or media artwork is kept visible when tracks change or player changes. Defaults to false.

Public functions

observe

suspend fun observe(player: Player?): Unit

Subscribes to updates from Player.Events and listens to

Player.EVENT_VIDEO_SIZE_CHANGED to determine pixelWidthHeightRatio-adjusted video size
Player.EVENT_RENDERED_FIRST_FRAME and Player.EVENT_TRACKS_CHANGEDto determine whether the surface is ready to be shown

Public properties

coverSurface

val coverSurface: Boolean

set to false when the Player emits Player.EVENT_RENDERED_FIRST_FRAME and reset back to true on Player.EVENT_TRACKS_CHANGED depending on the number and type of tracks.

keepContentOnReset

var keepContentOnReset: Boolean

player

@VisibleForTesting(otherwise = 2)
var player: Player?

videoSizeDp

val videoSizeDp: Size?

wraps Player.getVideoSize in Compose's Size, becomes null when either height or width of the video is zero. Takes into account VideoSize.pixelWidthHeightRatio to return a Size in Dp, i.e. device-independent pixel. To use this measurement in Compose's Drawing and Layout stages, convert it into pixels using Density.toPx. Note that for cases where pixelWidthHeightRatio is not equal to 1, the rescaling will be down, i.e. reducing the width or the height to achieve the same aspect ratio in square pixels.