Media3 provides a default PlayerView
that provides some
customization options. For any further customization, app developers are
expected to implement their own UI components.
Best practices
When implementing a media UI that connects to a Media3 Player
(for example
ExoPlayer
, MediaController
or a custom Player
implementation), apps are
advised to follow these best practices for the best UI experience.
Play/Pause button
The play and pause button does not directly correspond to a single player state. For example, a user should be able to restart playback after it ended or failed even if the player isn't paused.
To simplify the implementation, Media3 provides util methods to decide which
button to show (Util.shouldShowPlayButton
) and to handle button presses
(Util.handlePlayPauseButtonAction
):
Kotlin
val shouldShowPlayButton: Boolean = Util.shouldShowPlayButton(player) playPauseButton.setImageDrawable(if (shouldShowPlayButton) playDrawable else pauseDrawable) playPauseButton.setOnClickListener { Util.handlePlayPauseButtonAction(player) }
Java
boolean shouldShowPlayButton = Util.shouldShowPlayButton(player); playPauseButton.setImageDrawable(shouldShowPlayButton ? playDrawable : pauseDrawable); playPauseButton.setOnClickListener(view -> Util.handlePlayPauseButtonAction(player));
Listen to state updates
The UI component needs to add a Player.Listener
to be informed of state
changes that require a corresponding UI update. See
Listen to playback events for details.
Refreshing the UI can be costly and multiple player events often arrive
together. To avoid refreshing the UI too often in a short period of time, it's
generally better to listen to just onEvents
and trigger UI updates from there:
Kotlin
player.addListener(object : Player.Listener{ override fun onEvents(player: Player, events: Player.Events){ if (events.containsAny( Player.EVENT_PLAY_WHEN_READY_CHANGED, Player.EVENT_PLAYBACK_STATE_CHANGED, Player.EVENT_PLAYBACK_SUPPRESSION_REASON_CHANGED)) { updatePlayPauseButton() } if (events.containsAny(Player.EVENT_REPEAT_MODE_CHANGED)) { updateRepeatModeButton() } } })
Java
player.addListener(new Player.Listener() { @Override public void onEvents(Player player, Player.Events events) { if (events.containsAny( Player.EVENT_PLAY_WHEN_READY_CHANGED, Player.EVENT_PLAYBACK_STATE_CHANGED, Player.EVENT_PLAYBACK_SUPPRESSION_REASON_CHANGED)) { updatePlayPauseButton(); } if (events.containsAny(Player.EVENT_REPEAT_MODE_CHANGED)) { updateRepeatModeButton(); } } });
Handle available commands
A general purpose UI component that may need to work with different Player
implementations should check the available player commands to show or hide
buttons and to avoid calling unsupported methods:
Kotlin
nextButton.isEnabled = player.isCommandAvailable(Player.COMMAND_SEEK_TO_NEXT)
Java
nextButton.setEnabled(player.isCommandAvailable(Player.COMMAND_SEEK_TO_NEXT));
First frame shutter and image display
When a UI component displays video or images, it typically uses a placeholder shutter view until the real first frame or image is available. In addition, mixed video and image playback requires to hide and show the image view at appropriate times.
A common pattern to handle these updates is to listen to
Player.Listener.onEvents
for any change in selected tracks
(EVENT_TRACKS_CHANGED
) and for when the first video frame has been
rendered (EVENT_RENDERED_FIRST_FRAME
), as well as
ImageOutput.onImageAvailable
for when a new image is available:
Kotlin
override fun onEvents(player: Player, events: Player.Events) { if (events.contains(Player.EVENT_TRACKS_CHANGED)) { // If no video or image track: show shutter, hide image view. // Otherwise: do nothing to wait for first frame or image. } if (events.contains(Player.EVENT_RENDERED_FIRST_FRAME)) { // Hide shutter, hide image view. } } override fun onImageAvailable(presentationTimeUs: Long, bitmap: Bitmap) { // Show shutter, set image and show image view. }
Java
@Override public void onEvents(Player player, Events events) { if (events.contains(Player.EVENT_TRACKS_CHANGED)) { // If no video or image track: show shutter, hide image view. // Otherwise: do nothing to wait for first frame or image. } if (events.contains(Player.EVENT_RENDERED_FIRST_FRAME)) { // Hide shutter, hide image view. } } @Override public void onImageAvailable(long presentationTimeUs, Bitmap bitmap) { // Show shutter, set image and show image view. }