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Android MediaPlayer class throws java.lang.IllegalStateException after activity resumed

I'm trying to pause and resume VideoView with MediaPlayer in activity onPause() and onResume() methods, but in onResume() method MediaPlayer throws java.lang.IllegalStateException. I didn't release MediaPlayer but I think MediaPlayer automatically released after activity paused.
How should I handle it?
private MediaPlayer mediaPlayer;
void prepareVideo() {
videoView = new VideoView(context.getApplicationContext());
String path = "android.resource://" + getPackageName() + "/" +
R.raw.my_video;
videoView.setVideoPath(path);
}
videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
#Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer = mp;
mediaPlayer.start();
}
});
#Override
protected void onResume() {
super.onResume();
if (mediaPlayer != null) {
mediaPlayer.start();
}
}
#Override
protected void onPause() {
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.pause();
}
super.onPause();
}
The exception:
Caused by: java.lang.IllegalStateException
at android.media.MediaPlayer._start(Native Method)
at android.media.MediaPlayer.start(MediaPlayer.java:1194)
at co.myapp.app.reborn.myappTestActivity.onResume(myappTestActivity.java:370)
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1259)
at android.app.Activity.performResume(Activity.java:6347)
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3110)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3152) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1400) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:148) 
at android.app.ActivityThread.main(ActivityThread.java:5530) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:734) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624) 

Take a look at the mediaplayer state diagram on android documentation
MediaPlayer state diagram
According to the diagram you have to call setDataSource() and prepare() before calling start().
Probably something wrong happened before. Your logcat should point you in the right direction.
My guess is that your mediaplayer is not in paused state but in stopped state. So you have to call prepare and then start, not just start.
Unfortunately in this way your playback will restart from scratch.
You can use seek command for resuming a position saved during the activity pausing.

We just need to implement MediaPlayer.OnSeekCompleteListener interface and set MediaPlayer in onSeekComplete method.
private MediaPlayer mediaPlayer;
#Override
public void onSeekComplete(final MediaPlayer mp) {
mediaPlayer = mp;
}

I was facing this issue yesterday and I'd like to share my experience facing this issue, the root cause and the fix in my particular issue; this might be helpful for someone else.
This is what I found in my particular issue.
I´m running MediaPlayer in Fragment
When the phone goes to sleep (black screen), in the fragment-life-cycle the stop() function is call.
MediaPlayer recommends to release() MediaPlayer resources on STOP state.
When the phone resumes, it complains with illegal-state-exception because there are no MediaPlayer resource available, remember it was released in the STOPE state.
So, to fix it. I overrided start() state and I got another instance of MediaPlayer if it was null at that specific point in time. START state is called at resume time.
sample code
public class xMediaPlayer extends MediaPlayer
{
private static xMediaPlayer instance = null;
public static xMediaPlayer getInstance( )
{
if( instance == null )
instance = new xMediaPlayer( );
return instance;
}
}
Override start() on fragment
#Override
public void onStart() {
super.onStart();
mMediaPlayer = xMediaPlayer.getInstance( );
}

Releasing Media Player while preparing is causing app to freeze

I have two activities a main activity which has Recyclerview and a detailedActivity which is launched every time the user clicks on one of the items of the Recyclerview. The detailedActivity has a mediaplayer component that is being created everytime a detailedActivity is created. Now in the onDestroy method I always free the resources taken by the mediaPlayer by this code:
#Override
protected void onDestroy() {
if (mMediaPlayer != null) {
if (mMediaPlayer.isPlaying()) {
mMediaPlayer.stop();}
mMediaPlayer.release();
mMediaPlayer=null;
}
super.onDestroy();
}
The app freezes for a while every time I click the back button while the mediaplayer is still preparing. The message that I get in the logcat is this:
I/Choreographer: Skipped 112 frames! The application may be doing too much work on its main thread.
So this freezing only happens if I destroyed the activity while it is preparing but if it is already in the prepared state it won't happen. I use prepreAsync to fetch the media from the internet.
Thanks. Any help is highly appreciated. I have been stuck in this problem for days!

OK. I've kind of worked around the problem. I am writing this for anyone who might encounter the same situation as I did. I made two boolean flags in the scope of the class like this:
boolean prepared = false;
boolean cancel = false;
After that in the onpreapred method I set prepared to true.
mMediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
#Override
public void onPrepared(MediaPlayer mp) {
prepared = true;
}
});
In the onDestroy method I check whether the mediaplayer is already prepared or not if prepared I release it from the method its self.
#Override
protected void onDestroy() {
if (mMediaPlayer != null) {
if (mMediaPlayer.isPlaying()) {
mMediaPlayer.stop();
}
if (prepared) {
mMediaPlayer.release();
mMediaPlayer = null;
}
cancel = true;
}
super.onDestroy();
}
Otherwise, I set cancel to true and implement on OnBufferingUpdateListener interface and override its method and release the mediaplayer from there.
#Override
public void onBufferingUpdate(MediaPlayer mp, int percent) {
if (cancel) {
mp.reset();
mp.release();
mMediaPlayer = null;
Log.i("msg", " mp released");
}
}

Try to remove rechecking if mediaplayer is running or not.
#Override
protected void onDestroy() {
if (mMediaPlayer != null) {
mMediaPlayer.stop();
mMediaPlayer.release();
}
super.onDestroy();
}
If it still happens, try to remove checking mediaplayer in your onDestroy().
-- UPDATE --
This could be related with this bug:
https://code.google.com/p/android/issues/detail?id=959
This could be a help:
Android MediaPlayer reset freezes UI

How to release media player while preparing

I am working on music player app where I am doing streaming of music using MediaPlayer. Streaming is working fine but now I want If user press back button of the activity then it should stop preparing & release media player immediately.
Currently when it is preparing and if activity is being destroyed then I am releasing the MediaPlayer like this but when it release it then it hangs the application & show ANR.
#Override
protected void onDestroy() {
super.onDestroy();
if(mediaPlayer!=null) {
mediaPlayer.stop();
mediaPlayer.release();
}
}
I am initializing MediaPlayer like below
mediaPlayer = null;
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDataSource("http://www.samisite.com/sound/cropShadesofGrayMonkees.mp3");
Now I want when it start preparing then on back press when I am releasing in onDestory then it should not hang the app & release the media player smoothly.
Please help me what is the best way to do this. Thanks in advance
mediaPlayer.prepareAsync();

Check the answer here. And the MediaPlayer State Diagram from android code.
Edit:
#TGMCians I showed him the provided link, So, if the playback is still not ready or preparing, he can not call stop() until it's called onPrepared. I'm not sure that onPrepared keep called after the app onDestroy called. So, The full snip I think is:
private boolean mPrepared = false;
private boolean mCancel = false;
public void onPrepared(MediaPlayer player){
mPrepared = true;
if(mCancel){
player.release();
mPrepared = false;
mCancel = false;
//nullify your MediaPlayer reference
mediaPlayer = null;
}
}
private void cancelMedia(){
mCancel = true;
}
#Override
protected void onDestroy() {
super.onDestroy();
cancelMedia();
if (mediaPlayer != null && mPrepared) {
mediaPlayer.stop();
mediaPlayer.release();
mPrepared = false;
mediaPlayer = null;
}
}

How to play an mp3 file between a range of milliseconds using android MediaPlayer?

I am able to play an mp3 file using android's MediaPlayer object. But I would like to play between a range of milliseconds for example between 30000 ms to 40000 ms ( 10 seconds only ). How can I achieve this?
Currently the following code is what I have,
private MediaPlayer mPlayer;
public void play() {
try {
mPlayer = MediaPlayer.create(getApplicationContext(), R.raw.mp3_file);
if (mPlayer != null) {
int currentPosition = mPlayer.getCurrentPosition();
if (currentPosition + 30000 <= mPlayer.getDuration()) {
mPlayer.seekTo(currentPosition + 30000);
} else {
mPlayer.seekTo(mPlayer.getDuration());
}
mPlayer.start();
}
}
catch(Exception e) {
}
}
Any help is greatly appreciated. Thank you!

You can use the method:
public int getCurrentPosition ()
to obtain the current time in milSeconds maybe inside a Handler that runs every 1000 milSeconds and tests to see:
if(mPlayer.getCurrentPosition() >= (mPlayer.getDuration + 40000));
Dont forget to release the media file when you're done using it:
public void release();
mPlayer.release();
Releases resources associated with this MediaPlayer object. It is
considered good practice to call this method when you're done using
the MediaPlayer. In particular, whenever an Activity of an application
is paused (its onPause() method is called), or stopped (its onStop()
method is called), this method should be invoked to release the
MediaPlayer object, unless the application has a special need to keep
the object around. In addition to unnecessary resources (such as
memory and instances of codecs) being held, failure to call this
method immediately if a MediaPlayer object is no longer needed may
also lead to continuous battery consumption for mobile devices, and
playback failure for other applications if no multiple instances of
the same codec are supported on a device. Even if multiple instances
of the same codec are supported, some performance degradation may be
expected when unnecessary multiple instances are used at the same
time.

The best approach is to use a Handler to time the stopping of the playback. Start the player and then use the Handler's postDelayed to schedule the execution of a Runnable that will stop the player. You should also start the player only after the initial seek completes. Something like this:
public class PlayWord extends Activity implements MediaPlayer.OnSeekCompleteListener {
Handler mHandler;
MediaPlayer mPlayer;
int mStartTime = 6889;
int mEndTime = 7254;
final Runnable mStopAction = new Runnable() {
#Override
public void run() {
mPlayer.stop();
}
};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
final TextView tv = new TextView(this);
tv.setText("Playing...");
setContentView(tv);
mHandler = new Handler();
mPlayer = MediaPlayer.create(this, R.raw.nicholas);
mPlayer.setOnSeekCompleteListener(this);
mPlayer.seekTo(mStartTime);
}
#Override
public void onDestroy() {
mPlayer.release();
}
#Override
public void onSeekComplete (MediaPlayer mp) {
mPlayer.start();
mHandler.postDelayed(mStopAction, mEndTime - mStartTime);
}
}
Note also that the MediaPlayer.create method you are using returns a MediaPlayer that has already been prepared and prepare should not be called again like you are doing in your code.on the screen. I also added a call to release() when the activity exits.
Also, if you want to update the UI when the seek completes, be aware that this method is usually called from a non-UI thread. You will have to use the handler to post any UI-related actions.
I'm copied this from: Android: How to stop media (mp3) in playing when specific milliseconds come?

MediaPlayer gives different results if it has to wait longer before .start() is called

I'm trying to use a MediaPlayer instance to play several audio files individually, in response to various sensor events.
I've found that when I load up the clip to be played right before calling MediaPlayer.start(), the audio clip will play fine. However, the application takes a major performance hit. Ideally, each audio clip should be loaded into the MediaPlayer immediately after the last one was played, leaving the MediaPlayer ready to start playback the instant the SensorEvent comes in.
I would expect this to be simple, but now that I made the change the audio just doesn't play. PlayAudioClip() is definitely still being called as expected, but something is going wrong after that. No errors are thrown, so I don't think the MediaPlayer is changing state, but could something be interfering with in the time that it's waiting to play?
Here is a simplified version of my code:
public class MainActivity extends Activity implements SensorEventListener {
private Random numGenerator;
private SensorManager manager;
private Sensor accelerometer;
private MediaPlayer mediaPlayer;
private Uri[] audioClips;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initVariables();
prepareNextAudioClip(); //load first audioClip
}
#Override
public void onSensorChanged(SensorEvent event) {
if(conditionsRight()){
playAudioClip();
}
}
}
private void playAudioClip() {
mediaPlayer.start();
prepareNextAudioClip();
}
private void prepareNextAudioClip() {
try {
mediaPlayer.reset();
Uri audioClip = audioclips[(int) Math.floor(numGenerator.nextDouble()*audioClips.length)];
mediaPlayer.setDataSource(this, audioClip);
mediaPlayer.prepare();
} catch (Exception e) {
e.printStackTrace();
}
}
//Code below here isn't very important... handling setup and teardown
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {}
protected void onResume() {
super.onResume();
manager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
}
private void initVariables() {
audioClips = new Uri[]{
Uri.parse("android.resource://com.example.afraidofflying/" + R.raw.audio1),
Uri.parse("android.resource://com.example.afraidofflying/" + R.raw.audio2),
Uri.parse("android.resource://com.example.afraidofflying/" + R.raw.audio3)
};
numGenerator = new Random();
mediaPlayer = new MediaPlayer();
manager = (SensorManager)getSystemService(SENSOR_SERVICE);
accelerometer = manager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
if(null == accelerometer) finish();
}
protected void onPause() {
super.onPause();
manager.unregisterListener(this);
}
protected void onDestroy(){
mediaPlayer.release();
mediaPlayer = null;
}
}
PS: This has all been assuming I'll only use one instance of MediaPlayer but I'd also like input on if you think using multiple MediaPlayers and delegating each of them 1 audio clip would be advisable. My intuition is no because for my purposes I'd have to use 10-20 MediaPlayers, but it would be good to hear outside perspectives on it.

It's because you're resetting player right after starting playback.
private void playAudioClip() {
mediaPlayer.start(); //starting playback
prepareNextAudioClip(); //reset
}
if you want to play files in queue, than you can use one instance. But if you have to play several files simultaneusly, then you need to have several media player instances.

I think you have to look at subtle points regarding using Mediaplayer class
In your code you used:
initVariables();
prepareNextAudioClip(); //load first audioClip
initVariables() seems ok, Now lets see prepareNextAudioClip()
...
mediaPlayer.reset();
...
...
mediaPlayer.prepare();
The above code seems to corrupt Mediaplayer state machine. Please refer to http://developer.android.com/reference/android/media/MediaPlayer.html for details on using new, prepare,reset. It is better to write defensive MediaPlayer code using Errorlistener