Android MediaPlayer基本知識

文章目錄

• Valid and invalid states
• 如何擷取當前播放視頻的總長度和當前播放時間？

 

Valid and invalid states

Method Name	Valid Sates	Invalid States	Comments
attachAuxEffect	{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Idle, Error}	This method must be called after setDataSource. Calling it does not change the object state.
getAudioSessionId	any	{}	This method can be called in any state and calling it does not change the object state.
getCurrentPosition	{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
getDuration	{Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Idle, Initialized, Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
getVideoHeight	{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
getVideoWidth	{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
isPlaying	{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}	{Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
pause	{Started, Paused}	{Idle, Initialized, Prepared, Stopped, PlaybackCompleted, Error}	Successful invoke of this method in a valid state transfers the object to thePaused state. Calling this method in an invalid state transfers the object to theError state.
prepare	{Initialized, Stopped}	{Idle, Prepared, Started, Paused, PlaybackCompleted, Error}	Successful invoke of this method in a valid state transfers the object to thePrepared state. Calling this method in an invalid state throws an IllegalStateException.
prepareAsync	{Initialized, Stopped}	{Idle, Prepared, Started, Paused, PlaybackCompleted, Error}	Successful invoke of this method in a valid state transfers the object to thePreparing state. Calling this method in an invalid state throws an IllegalStateException.
release	any	{}	After release(), the object is no longer available.
reset	{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted, Error}	{}	After reset(), the object is like being just created.
seekTo	{Prepared, Started, Paused, PlaybackCompleted}	{Idle, Initialized, Stopped, Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
setAudioSessionId	{Idle}	{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted, Error}	This method must be called in idle state as the audio session ID must be known before calling setDataSource. Calling it does not change the object state.
setAudioStreamType	{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}	{Error}	Successful invoke of this method does not change the state. In order for the target audio stream type to become effective, this method must be called before prepare() or prepareAsync().
setAuxEffectSendLevel	any	{}	Calling this method does not change the object state.
setDataSource	{Idle}	{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted, Error}	Successful invoke of this method in a valid state transfers the object to theInitialized state. Calling this method in an invalid state throws an IllegalStateException.
setDisplay	any	{}	This method can be called in any state and calling it does not change the object state.
setSurface	any	{}	This method can be called in any state and calling it does not change the object state.
setLooping	{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}	{Error}	Successful invoke of this method in a valid state does not change the state. Calling this method in an invalid state transfers the object to theError state.
isLooping	any	{}	This method can be called in any state and calling it does not change the object state.
setOnBufferingUpdateListener	any	{}	This method can be called in any state and calling it does not change the object state.
setOnCompletionListener	any	{}	This method can be called in any state and calling it does not change the object state.
setOnErrorListener	any	{}	This method can be called in any state and calling it does not change the object state.
setOnPreparedListener	any	{}	This method can be called in any state and calling it does not change the object state.
setOnSeekCompleteListener	any	{}	This method can be called in any state and calling it does not change the object state.
setScreenOnWhilePlaying</>	any	{}	This method can be called in any state and calling it does not change the object state.
setVolume	{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}	{Error}	Successful invoke of this method does not change the state.
setWakeMode	any	{}	This method can be called in any state and calling it does not change the object state.
start	{Prepared, Started, Paused, PlaybackCompleted}	{Idle, Initialized, Stopped, Error}	Successful invoke of this method in a valid state transfers the object to theStarted state. Calling this method in an invalid state transfers the object to theError state.
stop	{Prepared, Started, Stopped, Paused, PlaybackCompleted}	{Idle, Initialized, Error}	Successful invoke of this method in a valid state transfers the object to theStopped state. Calling this method in an invalid state transfers the object to theError state.

如何擷取當前播放視頻的總長度和當前播放時間？

1) 根據上表的狀態要求調用mediaplayer.getDuration()得到總時間長度

2) 建立一個新線程，每秒調用mediaplayer.getCurrentPosition ()擷取當前播放時間