创建 MediaPlayer 时出错
Error while creating MediaPlayer
我的应用程序在使用此 错误日志 创建 MediaPlayer 时崩溃:
07-22 23:20:15.279 29029-29029/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.linkpulsion.bibix, PID: 29029
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.linkpulsion.bibix/com.linkpulsion.bibix.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access0(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
at android.content.ContextWrapper.getResources(ContextWrapper.java:90)
at android.view.ContextThemeWrapper.getResources(ContextThemeWrapper.java:74)
at android.media.MediaPlayer.create(MediaPlayer.java:986)
at android.media.MediaPlayer.create(MediaPlayer.java:969)
at com.linkpulsion.bibix.MainActivity.<init>(MainActivity.java:34)
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.Class.newInstance(Class.java:1650)
at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2655)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access0(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
第34行指向我创建的第一个MediaPlayer。
这是我的主要 class 发生的地方 :
private final MediaPlayer arracherlagorge = MediaPlayer.create(this,R.raw.arracherlagorge);
Button arracherlagorgeBut = (Button)findViewById(R.id.arracherLaGorgeBut);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.tool_bar);
setSupportActionBar(toolbar);
arracherlagorgeBut.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (arracherlagorge.isPlaying() || arracherlagorge.isLooping()) {
try {
arracherlagorge.pause();
arracherlagorge.seekTo(0);
arracherlagorge.prepare();
} catch (IOException e) {
e.printStackTrace();
}
} else {
if (arracherlagorge == null) {
Log.d("MEDIAPLAYER", "Error while creating MediaPlayer");
} else {
arracherlagorge.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
arracherlagorge.stop();
arracherlagorge.release();
}
});
arracherlagorge.start();
}
}
}
});
我的 MP3 文件比特率和格式符合 128kb/s 和 44.1 kHz 等规范:http://developer.android.com/guide/appendix/media-formats.html
我正在为 API 16+ 工作并在 API 21.
上进行测试
而不是
private final MediaPlayer arracherlagorge = MediaPlayer.create(this,R.raw.arracherlagorge);
试试这个:
private final MediaPlayer arracherlagorge = MediaPlayer.create(getResources(), R.raw.arracherlagorge);
我的应用程序在使用此 错误日志 创建 MediaPlayer 时崩溃:
07-22 23:20:15.279 29029-29029/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.linkpulsion.bibix, PID: 29029
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.linkpulsion.bibix/com.linkpulsion.bibix.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access0(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
at android.content.ContextWrapper.getResources(ContextWrapper.java:90)
at android.view.ContextThemeWrapper.getResources(ContextThemeWrapper.java:74)
at android.media.MediaPlayer.create(MediaPlayer.java:986)
at android.media.MediaPlayer.create(MediaPlayer.java:969)
at com.linkpulsion.bibix.MainActivity.<init>(MainActivity.java:34)
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.Class.newInstance(Class.java:1650)
at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2655)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2879)
at android.app.ActivityThread.access0(ActivityThread.java:182)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6141)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
第34行指向我创建的第一个MediaPlayer。 这是我的主要 class 发生的地方 :
private final MediaPlayer arracherlagorge = MediaPlayer.create(this,R.raw.arracherlagorge);
Button arracherlagorgeBut = (Button)findViewById(R.id.arracherLaGorgeBut);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.tool_bar);
setSupportActionBar(toolbar);
arracherlagorgeBut.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (arracherlagorge.isPlaying() || arracherlagorge.isLooping()) {
try {
arracherlagorge.pause();
arracherlagorge.seekTo(0);
arracherlagorge.prepare();
} catch (IOException e) {
e.printStackTrace();
}
} else {
if (arracherlagorge == null) {
Log.d("MEDIAPLAYER", "Error while creating MediaPlayer");
} else {
arracherlagorge.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
arracherlagorge.stop();
arracherlagorge.release();
}
});
arracherlagorge.start();
}
}
}
});
我的 MP3 文件比特率和格式符合 128kb/s 和 44.1 kHz 等规范:http://developer.android.com/guide/appendix/media-formats.html 我正在为 API 16+ 工作并在 API 21.
上进行测试而不是
private final MediaPlayer arracherlagorge = MediaPlayer.create(this,R.raw.arracherlagorge);
试试这个:
private final MediaPlayer arracherlagorge = MediaPlayer.create(getResources(), R.raw.arracherlagorge);