Errors

I wanted to start my Application but i got this error code(s):
08-25 14:33:37.861 8987-8987/com.example.max.mediaplayermitlistview E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.max.mediaplayermitlistview, PID: 8987
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.max.mediaplayermitlistvi ew/com.example.max.mediaplayermitlistview.Player}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(A ctivityThread.java:2328)
at android.app.ActivityThread.handleLaunchActivity(Ac tivityThread.java:2386)
at android.app.ActivityThread.access0(ActivityThre ad.java:169)
at android.app.ActivityThread$H.handleMessage(Activit yThread.java:1277)
at android.os.Handler.dispatchMessage(Handler.java:10 2)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.jav a:5476)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCa ller.run(ZygoteInit.java:1283)
at com.android.internal.os.ZygoteInit.main(ZygoteInit .java:1099)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.max.mediaplayermitlistview.Player.onCr eate(Player.java:77)
at android.app.Activity.performCreate(Activity.java:5 451)
at android.app.Instrumentation.callActivityOnCreate(I nstrumentation.java:1093)
at android.app.ActivityThread.performLaunchActivity(A ctivityThread.java:2292)
************at android.app.ActivityThread.handleLaunchActivity(Ac tivityThread.java:2386)
************at android.app.ActivityThread.access0(ActivityThre ad.java:169)
************at android.app.ActivityThread$H.handleMessage(Activit yThread.java:1277)
************at android.os.Handler.dispatchMessage(Handler.java:10 2)
************at android.os.Looper.loop(Looper.java:136)
************at android.app.ActivityThread.main(ActivityThread.jav a:5476)
************at java.lang.reflect.Method.invokeNative(Native Method)
************at java.lang.reflect.Method.invoke(Method.java:515)
************at com.android.internal.os.ZygoteInit$MethodAndArgsCa ller.run(ZygoteInit.java:1283)
************at com.android.internal.os.ZygoteInit.main(ZygoteInit .java:1099)
************at dalvik.system.NativeStart.main(Native Method)



Can you explain me what this error code means (where in the application the error is)?