我想在 android 中播放一个 mp3 文件,但我得到了这个错误:
java.lang.NullPointerException at HelloAndroid.playMusic
我的代码如下
package com.bestvalue.hello;
/*import android.util.Log;*/
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.media.MediaPlayer;
import android.net.Uri;
public class HelloAndroid extends Activity {
public static final String DebugTag = "LogInfo";
public MediaPlayer mp;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView tv = new TextView(this);
tv.setText("keke napep");
playMusic();
setContentView(tv);
Log.i(DebugTag, "Info about my app na");
}
public void playMusic () {
try {
Uri fileName = Uri.parse("http://www.perlgurl.org/podcast/archives/podcasts/PerlgurlPromo.mp3");
mp= MediaPlayer.create(this, fileName);
mp.start();
} catch (Exception e){
Log.e(DebugTag, "Error Playing File", e);
}
}
@Override
protected void onStop() {
if (mp != null) {
mp.stop();
mp.release();
}
super.onStop();
}
}
我将如何解决此错误?
谢谢
更新
package com.bestvalue.hello;
/*import android.util.Log;*/
import android.app.Activity;
//import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.media.AudioManager;
import android.media.MediaPlayer;
public class HelloAndroid extends Activity {
public static final String DebugTag = "LogInfo";
private MediaPlayer mp = new MediaPlayer();
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView tv = new TextView(this);
tv.setText("keke napep");
playMusic();
setContentView(tv);
}
public void playMusic () {
try {
String url = "http://www.perlgurl.org/podcast/archives/podcasts/PerlgurlPromo.mp3";
mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
mp.setDataSource(url);
mp.prepare();
mp.start();
} catch (Exception e){
Log.e(DebugTag, "Error Playing File", e);
}
}
@Override
protected void onStop() {
if (mp != null) {
mp.stop();
mp.release();
}
super.onStop();
}
}
实施一些答案后,我现在收到此错误:java.io.IOException: Prepare Failed .: status = 0x1