Develop Reference

Android: Registring to server Nullpointer exception at org.json.JSONTokener.nextCleanInternal

I did this tutorial https://www.youtube.com/watch?v=ArJDXM-HHqk&spfreload=10
and also copied this working code from other student: https://gist.github.com/anonymous/e0bfcd7a9e954ae574d59c123cb0c4ae
And still I get this error again and again:
01-01 23:24:00.727 2759-2759/com.example.loginapp E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.NullPointerException
at org.json.JSONTokener.nextCleanInternal(JSONTokener.java:116)
at org.json.JSONTokener.nextValue(JSONTokener.java:94)
at org.json.JSONObject.<init>(JSONObject.java:154)
at org.json.JSONObject.<init>(JSONObject.java:171)
at com.example.loginapp.BackgroundTask.onPostExecute(BackgroundTask.java:52)
at com.example.loginapp.BackgroundTask.onPostExecute(BackgroundTask.java:26)
at android.os.AsyncTask.finish(AsyncTask.java:631)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5413)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
at dalvik.system.NativeStart.main(Native Method)

Silly me, I had a typo in the method name, "Register" instead of "register".
now it works fine.

Error APK when built with key store

My app run very good when built test but when build it with keystore and run my app it force close and show error
E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.NullPointerException
at tuannt.appweather.f.f.a(Unknown Source)
at tuannt.appweather.e.a.a(Unknown Source)
at tuannt.appweather.e.a.onPostExecute(Unknown Source)
at android.os.AsyncTask.finish(AsyncTask.java:631)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:5162)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:744)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
What happened with my apk?

A strange Exception about notification: ClassCastException: RemoteViews$SetOnClickPendingIntent cannot be cast to RemoteViews$ReflectionAction

I have encounteredd a problem. I collect a exception message about notification for startForeground. It mainly appears on SamSung GT-I9300, API 15. Is there any clue about it ? Expect your fabulous analysis. Thanks
Bad notification for startForeground: java.lang.ClassCastException:
android.widget.RemoteViews$SetOnClickPendingIntent cannot be cast to
android.widget.RemoteViews$ReflectionAction
android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260)
android.os.Handler.dispatchMessage(Handler.java:99)
android.os.Looper.loop(Looper.java:137)
android.app.ActivityThread.main(ActivityThread.java:4424)
java.lang.reflect.Method.invokeNative(Native Method)
java.lang.reflect.Method.invoke(Method.java:511)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:825)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:592)
dalvik.system.NativeStart.main(Native Method)

ArrayIndexOutOfBoundsException in android.view.WindowManagerGlobal

I have received this error in my remote app crash reporter:
java.lang.ArrayIndexOutOfBoundsException: length=1; index=1
at android.view.WindowManagerGlobal.closeAll(WindowManagerGlobal.java:325)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3590)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3756)
at android.app.ActivityThread.access$800(ActivityThread.java:150)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1286)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5279)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
at dalvik.system.NativeStart.main(Native Method)
Is this a known bug in Android? I have no more information about the crash. Do you have any idea about what can I do to get the cause?

Array index start at 0
you have to subsract 1

Unable to start activity NullPointerException-onActivityCreated

My App crash rarely
i want to get off this bug for ever.
this is the log that users Report
i tried so long on this but nothing helps
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.xxx.xxx/com.xxx.xxx.Master_}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2072)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2097)
at android.app.ActivityThread.access$600(ActivityThread.java:136)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1207)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4787)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:556)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.xxx.xxx.HomeFragment.onActivityCreated(HomeFragment.java:140)
at android.support.v4.app.Fragment.performActivityCreated(Fragment.java:1508)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:958)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1115)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1097)
at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:1895)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:566)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1163)
at android.app.Activity.performStart(Activity.java:5018)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2045)
... 11 more