I am trying to create Mediaplayer session with given uri. but it causes NullpointerException .
Uri uri = Uri.parse(path);
// Creating MediaPlayer with given song's URI
if (mediaPlayer != null) {
mediaPlayer.stop();
mediaPlayer.release();
}
mediaPlayer = MediaPlayer.create(this, uri);
try {
// Setting the MediaPlayer Listener
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
seekBar.setMax(mp.getDuration());
mediaPlayer.start();
changeSeekbar();
}
});
} catch (Exception e) {
Log.e("ERROR", e.toString());
}
Given Logcat:
2020-04-07 22:21:05.289 12237-12237/com.example.musicappresearch2 E/Path: /storage/emulated/0/Music/Alone - Viren.mp3
2020-04-07 22:21:05.289 12237-12237/com.example.musicappresearch2 E/ERROR: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.media.MediaPlayer.setOnPreparedListener(android.media.MediaPlayer$OnPreparedListener)' on a null object reference
Could you Tell me What i am doing wrong? Thanks.
There are two ways to write this code, both tested on the device
First of all, make sure you handle android.permission.READ_EXTERNAL_STORAGE
correctly and you really have correct Uri.
MediaPlayer.create(this, uri);
will fail if either context or uri are invalid.
MediaPlayer.create(this, uri);
which itself already prepares player so you don't need .prepareAsync()
in this situation. and your code is good to go.
another way:
mediaPlayer = new MediaPlayer(); // hence, we don't use .create, manually instantiate
try {
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDataSource(this, uri);
mediaPlayer.setOnPreparedListener(mp -> {
mediaPlayer.start();
});
/* use async, if you don't want to block UI thread
keep in mind, this should be called after setting listener
because it might prepare even until the listener has been set */
mediaPlayer.prepareAsync();
} catch (Exception e) {
Log.e("ERROR", e.toString());
}
Try this:
Uri uri = Uri.parse(path);
mediaPlayer = new MediaPlayer();
try {
// mediaPlayer.setDataSource(String.valueOf(uri));
mediaPlayer.setDataSource(MainActivity.this,uri);
} catch (IOException e) {
e.printStackTrace();
}
try {
mediaPlayer.prepare();
} catch (IOException e) {
e.printStackTrace();
}
mediaPlayer.start();
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