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Android APIs
public abstract class

TransportPerformer

extends Object
java.lang.Object
   ↳ android.support.v4.media.TransportPerformer

Class Overview

Implemented by the playback side of the media system, to respond to requests to perform actions and to retrieve its current state. These requests may either come from key events dispatched directly to your UI, or events sent over a media button event receiver that this class keeps active while your window is in focus.

Summary

Public Constructors
TransportPerformer()
Public Methods
void onAudioFocusChange(int focusChange)
Report that audio focus has changed on the app.
int onGetBufferPercentage()
Request to find out how much of the media has been buffered on the local device.
abstract long onGetCurrentPosition()
Request to return the current playback position, in milliseconds.
abstract long onGetDuration()
Request to return the duration of the current media, in milliseconds.
int onGetTransportControlFlags()
Retrieves the flags for the media transport control buttons that this transport supports.
abstract boolean onIsPlaying()
Request to find out whether the player is currently playing its media.
boolean onMediaButtonDown(int keyCode, KeyEvent event)
Report that a media button has been pressed.
boolean onMediaButtonUp(int keyCode, KeyEvent event)
Report that a media button has been released.
abstract void onPause()
Request to pause playback of the media, staying at the current playback position and other state so a later call to onStart() will resume at the same place.
abstract void onSeekTo(long pos)
Request to move the current playback position.
abstract void onStart()
Request to start playback on the media, resuming from whatever current state (position etc) it is in.
abstract void onStop()
Request to completely stop playback of the media, clearing whatever state the player thinks is appropriate.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public TransportPerformer ()

Public Methods

public void onAudioFocusChange (int focusChange)

Report that audio focus has changed on the app. This only happens if you have indicated you have started playing with TransportController.startPlaying, which takes audio focus for you.

Parameters
focusChange The type of focus change, as per OnAudioFocusChangeListener.onAudioFocusChange. The default implementation will deliver a KEYCODE_MEDIA_STOP when receiving AUDIOFOCUS_LOSS.

public int onGetBufferPercentage ()

Request to find out how much of the media has been buffered on the local device.

Returns
  • Return a percentage (0-100) indicating how much of the total data has been buffered. The default implementation returns 100, meaning the content is always on the local device.

public abstract long onGetCurrentPosition ()

Request to return the current playback position, in milliseconds.

public abstract long onGetDuration ()

Request to return the duration of the current media, in milliseconds.

public int onGetTransportControlFlags ()

Retrieves the flags for the media transport control buttons that this transport supports. Result is a combination of the following flags: FLAG_KEY_MEDIA_PREVIOUS, FLAG_KEY_MEDIA_REWIND, FLAG_KEY_MEDIA_PLAY, FLAG_KEY_MEDIA_PLAY_PAUSE, FLAG_KEY_MEDIA_PAUSE, FLAG_KEY_MEDIA_STOP, FLAG_KEY_MEDIA_FAST_FORWARD, FLAG_KEY_MEDIA_NEXT

The default implementation returns: FLAG_KEY_MEDIA_PLAY, FLAG_KEY_MEDIA_PLAY_PAUSE, FLAG_KEY_MEDIA_PAUSE, and FLAG_KEY_MEDIA_STOP

public abstract boolean onIsPlaying ()

Request to find out whether the player is currently playing its media.

public boolean onMediaButtonDown (int keyCode, KeyEvent event)

Report that a media button has been pressed. This is like onKeyDown(int, android.view.KeyEvent) but will only deliver media keys. The default implementation handles these keys:

Parameters
keyCode The code of the media key.
event The full key event.
Returns
  • Indicate whether the key has been consumed. The default implementation always returns true. This only matters for keys being dispatched here from TransportController.dispatchKeyEvent, and determines whether the key continues on to its default key handling (which for media keys means being delivered to the current media remote control, which should be us).

public boolean onMediaButtonUp (int keyCode, KeyEvent event)

Report that a media button has been released. This is like onKeyUp(int, android.view.KeyEvent) but will only deliver media keys. The default implementation does nothing.

Parameters
keyCode The code of the media key.
event The full key event.
Returns
  • Indicate whether the key has been consumed. The default implementation always returns true. This only matters for keys being dispatched here from TransportController.dispatchKeyEvent, and determines whether the key continues on to its default key handling (which for media keys means being delivered to the current media remote control, which should be us).

public abstract void onPause ()

Request to pause playback of the media, staying at the current playback position and other state so a later call to onStart() will resume at the same place.

public abstract void onSeekTo (long pos)

Request to move the current playback position.

Parameters
pos New position to move to, in milliseconds.

public abstract void onStart ()

Request to start playback on the media, resuming from whatever current state (position etc) it is in.

public abstract void onStop ()

Request to completely stop playback of the media, clearing whatever state the player thinks is appropriate.