为了播放在线音乐，我在后台做了例外。我无法解决问题。
01-08 09:42:05.199: E/MediaPlayer(16257): Unable to to create media player
01-08 09:42:05.209: W/System.err(16257): java.io.IOException: setDataSource failed.: status=0x80000000
01-08 09:42:05.229: W/System.err(16257): at android.media.MediaPlayer._setDataSource(Native Method)
01-08 09:42:05.229: W/System.err(16257): at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1000)
01-08 09:42:05.229: W/System.err(16257): at android.media.MediaPlayer.setDataSource(MediaPlayer.java:960)
01-08 09:42:05.229: W/System.err(16257): at com.example.audioplayer.MainActivity$Player.doInBackground(MainActivity.java:89)
01-08 09:42:05.229: W/System.err(16257): at com.example.audioplayer.MainActivity$Player.doInBackground(MainActivity.java:1)
01-08 09:42:05.229: W/System.err(16257): at android.os.AsyncTask$2.call(AsyncTask.java:287)
01-08 09:42:05.229: W/System.err(16257): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
01-08 09:42:05.229: W/System.err(16257): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
01-08 09:42:05.229: W/System.err(16257): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
01-08 09:42:05.239: W/System.err(16257): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
01-08 09:42:05.239: W/System.err(16257): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
01-08 09:42:05.239: W/System.err(16257): at java.lang.Thread.run(Thread.java:856)
01-08 09:42:05.389: D/Prepared(16257): //false
01-08 09:42:05.389: E/MediaPlayer(16257): start called in state 1
01-08 09:42:05.389: E/MediaPlayer(16257): error (-38, 0)
01-08 09:42:05.449: E/MediaPlayer(16257): Error (-38,0)
这是代码：
public class MainActivity extends Activity {
private Button btn;
/**
* help to toggle between play and pause.
*/
private boolean playPause;
private MediaPlayer mediaPlayer;
/**
* remain false till media is not completed, inside OnCompletionListener make it true.
*/
private boolean intialStage = true;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button) findViewById(R.id.button1);
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
btn.setOnClickListener(pausePlay);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
private OnClickListener pausePlay = new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
// TODO Auto-generated method stub
if (!playPause) {
btn.setBackgroundResource(R.drawable.button_pause);
if (intialStage)
new Player()
.execute("http://www.virginmegastore.me/Library/Music/CD_001214/Tracks/Track1.mp3");
else {
if (!mediaPlayer.isPlaying())
mediaPlayer.start();
}
playPause = true;
} else {
btn.setBackgroundResource(R.drawable.button_play);
if (mediaPlayer.isPlaying())
mediaPlayer.pause();
playPause = false;
}
}
};
/**
* preparing mediaplayer will take sometime to buffer the content so prepare it inside the background thread and starting it on UI thread.
* @author piyush
*
*/
class Player extends AsyncTask<String, Void, Boolean> {
private ProgressDialog progress;
@Override
protected Boolean doInBackground(String... params) {
// TODO Auto-generated method stub
Boolean prepared;
try {
mediaPlayer.setDataSource(params[0]);//line 89
mediaPlayer.setOnCompletionListener(new OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
// TODO Auto-generated method stub
intialStage = true;
playPause=false;
btn.setBackgroundResource(R.drawable.button_play);
mediaPlayer.stop();
mediaPlayer.reset();
}
});
mediaPlayer.prepare();
prepared = true;
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
Log.d("IllegarArgument", e.getMessage());
prepared = false;
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
prepared = false;
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
prepared = false;
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
prepared = false;
e.printStackTrace();
}
return prepared;
}
@Override
protected void onPostExecute(Boolean result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
if (progress.isShowing()) {
progress.cancel();
}
Log.d("Prepared", "//" + result);
mediaPlayer.start();
intialStage = false;
}
public Player() {
progress = new ProgressDialog(MainActivity.this);
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
this.progress.setMessage("Buffering...");
this.progress.show();
}
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
if (mediaPlayer != null) {
mediaPlayer.reset();
mediaPlayer.release();
mediaPlayer = null;
}
}
}
链接正确。我已经提到了第89行产生的异常。请看那里出了什么问题。
提前致谢...
答案 0 :(得分：15)
您不需要编写自己的AsyncTask来处理此问题，MediaPlayer类已经有PrepareAsync方法，它将为您处理后台加载。
尝试这样的事情：
package com.mypackage.test;
import android.app.Activity;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import java.io.IOException;
public class MainActivity extends Activity {
private Button btn;
private MediaPlayer mediaPlayer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button) findViewById(R.id.button1);
setVolumeControlStream(AudioManager.STREAM_MUSIC);
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
try {
mediaPlayer.setDataSource("http://www.virginmegastore.me/Library/Music/CD_001214/Tracks/Track1.mp3");
mediaPlayer.prepareAsync();
mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer.start();
}
});
} catch (IOException e) {
e.printStackTrace();
}
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mediaPlayer.isPlaying()) {
mediaPlayer.pause();
} else {
mediaPlayer.start();
}
}
});
}
}
我也为了自己的利益简化了一些代码。
另外，不要忘记在清单中包含INTERNET权限：
<uses-permission android:name="android.permission.INTERNET"/>