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.

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)

Android Studio seems to build old version of project

I am wondering if this is some bug in Android Studio or I am simply lack od knowladge but straight to the point.
I am writing simple client-server via bluetooth app on android. At some point I encoured following problem:
07-11 18:59:20.553 10364-10364/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.IllegalStateException: Could not find a method parujUrzadzenia(View) in the activity class com.example.pc.klient_serwerbluetooth.Klient for onClick handler on view class android.widget.Button with id 'button6'
at android.view.View$1.onClick(View.java:3775)
at android.view.View.performClick(View.java:4421)
at android.view.View$PerformClick.run(View.java:18190)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:175)
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)
Caused by: java.lang.NoSuchMethodException: parujUrzadzenia [class android.view.View]
at java.lang.Class.getConstructorOrMethod(Class.java:460)
at java.lang.Class.getMethod(Class.java:915)
at android.view.View$1.onClick(View.java:3768)
at android.view.View.performClick(View.java:4421)
at android.view.View$PerformClick.run(View.java:18190)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:175)
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)
07-11 19:34:00.498 449-522/? E/ActivityManager﹕ The package com.example.pc.klient_serwerbluetooth is not found. Failure starting process com.example.pc.klient_serwerbluetooth
For what I understand Android Studio can't find method parujUrzadzenia(View) that is marked in button6's properties as onClick method...the funny thing is i deleted this button in my way of solving this problem.
I can't post picture of my project due to low reputation but like I said. I've deleted the reference to method from .xml and method from .java file and got an error saying that there is no required onClick method. So I deleted this whole button and still got this error.
Any advices will be greatly appreciated.

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

Proguard android keep class

I've enabled android proguard. After sing in i've run my app on device. its throws below error.
FATAL EXCEPTION: main
java.lang.NumberFormatException: Invalid int: "null"
at java.lang.Integer.invalidInt(Integer.java:138)
at java.lang.Integer.parseInt(Integer.java:355)
at java.lang.Integer.parseInt(Integer.java:332)
at lf.a(Source:481)
at lf.onPostExecute(Source:1)
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:137)
at android.app.ActivityThread.main(ActivityThread.java:5041)
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:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
What class need to keep in proguard? if disable proguard its working correctly.