Develop Reference

Quickblox-chat in android AndroidRuntime java.lang.NoClassDefFoundError: com.quickblox.chat.QBChatService

I have download quickblox quickblox-chat where I followed all these rules with quickblox-chat At Login closed with exceptions errors
Now I got exception log Here
java.lang.NoClassDefFoundError: com.quickblox.chat.QBChatService
at com.quickblox.sample.chat.ui.activities.SplashActivity.onCreate(SplashActivity.java:41)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.Activity.performCreate(Activity.java:5104)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.ActivityThread.access$600(ActivityThread.java:141)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.os.Handler.dispatchMessage(Handler.java:99)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.os.Looper.loop(Looper.java:137)
02-25 11:11:55.251: E/AndroidRuntime(897): at android.app.ActivityThread.main(ActivityThread.java:5041)
02-25 11:11:55.251: E/AndroidRuntime(897): at java.lang.reflect.Method.invokeNative(Native Method)
02-25 11:11:55.251: E/AndroidRuntime(897): at java.lang.reflect.Method.invoke(Method.java:511)
02-25 11:11:55.251: E/AndroidRuntime(897): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
02-25 11:11:55.251: E/AndroidRuntime(897): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
02-25 11:11:55.251: E/AndroidRuntime(897): at dalvik.system.NativeStart.main(Native Method)
02-25 11:11:58.441: I/Process(897): Sending signal. PID: 897 SIG: 9
Any solution please?

You can Also add Both jar file to Libs directory in project and clean and build project.

App not finding resources after locale change in Android

I am working on a project which requires on the fly language changes. I am attempting to set the desired Locale but as soon as I do, the app crashes complaining that it cannot find Resources (things like R.layout.* R.drawable.*)
This is the code I am using to set the new Locale:
String languageToLoad = "es";
Locale locale = new Locale(languageToLoad);
Locale.setDefault(locale);
Configuration config = new Configuration();
config.locale = locale;
getBaseContext().getResources().updateConfiguration(config,
getBaseContext().getResources().getDisplayMetrics());
Edit: added log
E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.flavorburst.mcdonalds/com.flavorburst.mcdonalds.MyActivity}: android.view.InflateException: Binary XML file line #25: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
at android.app.ActivityThread.access$600(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
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)
Caused by: android.view.InflateException: Binary XML file line #25: Error inflating class fragment
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:270)
at android.app.Activity.setContentView(Activity.java:1881)
at com.flavorburst.mcdonalds.MyActivity.onCreate(MyActivity.java:106)
at android.app.Activity.performCreate(Activity.java:5104)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
at android.app.ActivityThread.access$600(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
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$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.content.res.Resources$NotFoundException: String array resource ID #0x7f08001e
at android.content.res.Resources.getStringArray(Resources.java:451)
at com.flavorburst.mcdonalds.NavigationDrawerFragment.onCreate(NavigationDrawerFragment.java:91)
at android.app.Fragment.performCreate(Fragment.java:1673)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:854)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
at android.app.FragmentManagerImpl.addFragment(FragmentManager.java:1137)
at android.app.Activity.onCreateView(Activity.java:4717)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:680)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:746)
at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:270)
at android.app.Activity.setContentView(Activity.java:1881)
at com.flavorburst.application.MyActivity.onCreate(MyActivity.java:106)
at android.app.Activity.performCreate(Activity.java:5104)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
at android.app.ActivityThread.access$600(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
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)

This error:
Caused by: android.content.res.Resources$NotFoundException: String array resource ID #0x7f08001e at android.content.res.Resources.getStringArray(Resources.java:451) at com.flavorburst.mcdonalds.NavigationDrawerFragment
refers to a string array that you have defined in one of your XML files, but you forgot to create the string array value in /values/array.xml. For example, in one of your XML files, you may have specified a string array value of "arrayNames", but you forgot to declare it in /values/array.xml like:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string-array name="arrayNames"/>
</resources>
So, at runtime, the compiler will complain that it cannot find "arrayNames" in /values/array.xml. Hence, the error you got when you run your app.

Have you tried to clean and rebuild your project? If you are using eclipse got to Project -> Clean. And then build again. If you are using Android Studio and gradle, type the following command line on a terminal:
./gradlew clean
or
use the Build -> Rebuild Project

Could not find appcompat_v7.apk and android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1880)

i have problem. when run and i debug program i have
[2014-11-14 03:57:23 - Traffic] Android Launch!
[2014-11-14 03:57:23 - Traffic] adb is running normally.
[2014-11-14 03:57:23 - Traffic] Performing com.fuad.traffic.MainActivity activity launch
[2014-11-14 03:57:26 - Traffic] Uploading Traffic.apk onto device 'YT910DUTNU'
[2014-11-14 03:57:26 - Traffic] Installing Traffic.apk...
[2014-11-14 03:57:33 - Traffic] Success!
[2014-11-14 03:57:33 - appcompat_v7] Could not find appcompat_v7.apk!
[2014-11-14 03:57:33 - Traffic] Starting activity com.fuad.traffic.MainActivity on device YT910DUTNU
that is my problem, and when i running in phone this i have problem again like this my problem
11-14 19:10:02.090: W/dalvikvm(28725): Unable to resolve superclass of Lcom/fuad/traffic/MainActivity; (83)
11-14 19:10:02.090: W/dalvikvm(28725): Link of class 'Lcom/fuad/traffic/MainActivity;' failed
11-14 19:10:02.090: W/dalvikvm(28725): threadid=1: thread exiting with uncaught exception (group=0x40b019f0)
11-14 19:10:02.100: E/AndroidRuntime(28725): FATAL EXCEPTION: main
11-14 19:10:02.100: E/AndroidRuntime(28725): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.fuad.traffic/com.fuad.traffic.MainActivity}: java.lang.ClassNotFoundException: com.fuad.traffic.MainActivity
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1880)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread.access$600(ActivityThread.java:123)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.os.Handler.dispatchMessage(Handler.java:99)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.os.Looper.loop(Looper.java:137)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread.main(ActivityThread.java:4424)
11-14 19:10:02.100: E/AndroidRuntime(28725): at java.lang.reflect.Method.invokeNative(Native Method)
11-14 19:10:02.100: E/AndroidRuntime(28725): at java.lang.reflect.Method.invoke(Method.java:511)
11-14 19:10:02.100: E/AndroidRuntime(28725): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:817)
11-14 19:10:02.100: E/AndroidRuntime(28725): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
11-14 19:10:02.100: E/AndroidRuntime(28725): at dalvik.system.NativeStart.main(Native Method)
11-14 19:10:02.100: E/AndroidRuntime(28725): Caused by: java.lang.ClassNotFoundException: com.fuad.traffic.MainActivity
11-14 19:10:02.100: E/AndroidRuntime(28725): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
11-14 19:10:02.100: E/AndroidRuntime(28725): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
11-14 19:10:02.100: E/AndroidRuntime(28725): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
11-14 19:10:02.100: E/AndroidRuntime(28725): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1871)
11-14 19:10:02.100: E/AndroidRuntime(28725): ... 11 more
thanx for master in stackoverflow.com :D

after importing appcompat_v7 check its properties android section and be sure that Is Library is checked! and then add appcompat_v7 project to your project in your project > properties > android and then clean and rebuild your project!

Try:
Right Click on Package Explorer
Import
Android > Existing Android Code into Workspace > Next
Browse > ~/sdk/extras/android/support/v7/appcompat
Select the package. Checkbox "Copy projects into workspace" > Finish
Right Click in YOUR PROJECT > Properties > Android
In the section of Library > Add > appcompat > OK
Finally go to Project (in the menu of eclipse) > Clean ..
Tell us if you tried something and what happened

for #mohammad, i have found the problem, in properties>java build path>project, the problem is there are have folder appcompat. and it's must delete. and when i delete it it's work. but the next problem when i run the program is like this
'11-14 19:24:44.379: W/dalvikvm(29518): VFY: unable to resolve virtual method 292: Landroid/app/Notification$Builder;.setPriority (I)Landroid/app/Notification$Builder;
11-14 19:24:44.379: W/dalvikvm(29518): threadid=1: thread exiting with uncaught exception (group=0x40b019f0)
11-14 19:24:44.389: E/AndroidRuntime(29518): FATAL EXCEPTION: main
11-14 19:24:44.389: E/AndroidRuntime(29518): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.fuad.traffic/com.fuad.traffic.MainActivity}: android.view.InflateException: Binary XML file line #15: Error inflating class fragment
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread.access$600(ActivityThread.java:123)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.os.Handler.dispatchMessage(Handler.java:99)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.os.Looper.loop(Looper.java:137)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread.main(ActivityThread.java:4424)
11-14 19:24:44.389: E/AndroidRuntime(29518): at java.lang.reflect.Method.invokeNative(Native Method)
11-14 19:24:44.389: E/AndroidRuntime(29518): at java.lang.reflect.Method.invoke(Method.java:511)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:817)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
11-14 19:24:44.389: E/AndroidRuntime(29518): at dalvik.system.NativeStart.main(Native Method)
11-14 19:24:44.389: E/AndroidRuntime(29518): Caused by: android.view.InflateException: Binary XML file line #15: Error inflating class fragment
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:697)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:268)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.Activity.setContentView(Activity.java:1837)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.fuad.traffic.MainActivity.onCreate(MainActivity.java:15)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.Activity.performCreate(Activity.java:4470)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
11-14 19:24:44.389: E/AndroidRuntime(29518): ... 11 more
11-14 19:24:44.389: E/AndroidRuntime(29518): Caused by: java.lang.IllegalStateException: The meta-data tag in your app's AndroidManifest.xml does not have the right value. Expected 6111000 but found 0. You must have the following declaration within the <application> element: <meta-data android:name="com.google.android.gms.version" android:value="#integer/google_play_services_version" />
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.common.GooglePlayServicesUtil.E(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.common.GooglePlayServicesUtil.isGooglePlayServicesAvailable(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.internal.u.S(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.internal.u.R(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.MapsInitializer.initialize(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.SupportMapFragment$b.my(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.SupportMapFragment$b.a(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.dynamic.a.a(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.dynamic.a.onInflate(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at com.google.android.gms.maps.SupportMapFragment.onInflate(Unknown Source)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2158)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:297)
11-14 19:24:44.389: E/AndroidRuntime(29518): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:669)
11-14 19:24:44.389: E/AndroidRuntime(29518): ... 21 more
'

How to identify the error in logcat

I have some error in logcat but i dont know how to identify it. pls help me to find out this problem. My system crashes after running the emulator. I don't know what is an error in my project.
Thanks in advance.
02-14 16:45:44.527: D/dalvikvm(562): Not late-enabling CheckJNI (already on)
02-14 16:45:46.407: I/ActivityThread(562): Pub polito.mailandroid: polito.mailandroid.ui.ElementProvider
02-14 16:45:46.417: D/AndroidRuntime(562): Shutting down VM
02-14 16:45:46.417: W/dalvikvm(562): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
02-14 16:45:46.487: E/AndroidRuntime(562): FATAL EXCEPTION: main
02-14 16:45:46.487: E/AndroidRuntime(562): java.lang.RuntimeException: Unable to get provider polito.mailandroid.ui.ElementProvider: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.installProvider(ActivityThread.java:4240)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.installContentProviders(ActivityThread.java:3992)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.handleBindApplication(ActivityThread.java:3946)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.access$1300(ActivityThread.java:123)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1185)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.os.Looper.loop(Looper.java:137)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.main(ActivityThread.java:4424)
02-14 16:45:46.487: E/AndroidRuntime(562): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 16:45:46.487: E/AndroidRuntime(562): at java.lang.reflect.Method.invoke(Method.java:511)
02-14 16:45:46.487: E/AndroidRuntime(562): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
02-14 16:45:46.487: E/AndroidRuntime(562): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
02-14 16:45:46.487: E/AndroidRuntime(562): at dalvik.system.NativeStart.main(Native Method)
02-14 16:45:46.487: E/AndroidRuntime(562): Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
02-14 16:45:46.487: E/AndroidRuntime(562): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
02-14 16:45:46.487: E/AndroidRuntime(562): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
02-14 16:45:46.487: E/AndroidRuntime(562): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
02-14 16:45:46.487: E/AndroidRuntime(562): at android.app.ActivityThread.installProvider(ActivityThread.java:4225)
02-14 16:45:46.487: E/AndroidRuntime(562): ... 12 more
02-14 16:46:16.637: I/Process(562): Sending signal. PID: 562 SIG: 9
02-14 17:00:46.667: I/ActivityThread(644): Pub polito.mailandroid: polito.mailandroid.ui.ElementProvider
02-14 17:00:46.667: D/AndroidRuntime(644): Shutting down VM
02-14 17:00:46.717: W/dalvikvm(644): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
02-14 17:00:46.727: E/AndroidRuntime(644): FATAL EXCEPTION: main
02-14 17:00:46.727: E/AndroidRuntime(644): java.lang.RuntimeException: Unable to get provider polito.mailandroid.ui.ElementProvider: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.installProvider(ActivityThread.java:4240)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.installContentProviders(ActivityThread.java:3992)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.handleBindApplication(ActivityThread.java:3946)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.access$1300(ActivityThread.java:123)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1185)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.os.Looper.loop(Looper.java:137)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.main(ActivityThread.java:4424)
02-14 17:00:46.727: E/AndroidRuntime(644): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 17:00:46.727: E/AndroidRuntime(644): at java.lang.reflect.Method.invoke(Method.java:511)
02-14 17:00:46.727: E/AndroidRuntime(644): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
02-14 17:00:46.727: E/AndroidRuntime(644): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
02-14 17:00:46.727: E/AndroidRuntime(644): at dalvik.system.NativeStart.main(Native Method)
02-14 17:00:46.727: E/AndroidRuntime(644): Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
02-14 17:00:46.727: E/AndroidRuntime(644): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
02-14 17:00:46.727: E/AndroidRuntime(644): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
02-14 17:00:46.727: E/AndroidRuntime(644): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
02-14 17:00:46.727: E/AndroidRuntime(644): at android.app.ActivityThread.installProvider(ActivityThread.java:4225)
02-14 17:00:46.727: E/AndroidRuntime(644): ... 12 more
02-14 17:09:00.347: I/ActivityThread(692): Pub polito.mailandroid: polito.mailandroid.ui.ElementProvider
02-14 17:09:00.437: D/AndroidRuntime(692): Shutting down VM
02-14 17:09:00.437: W/dalvikvm(692): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
02-14 17:09:00.457: E/AndroidRuntime(692): FATAL EXCEPTION: main
02-14 17:09:00.457: E/AndroidRuntime(692): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{polito.mailandroid.ui/polito.mailandroid.ui.ui.LoginUI}: java.lang.ClassNotFoundException: polito.mailandroid.ui.ui.LoginUI
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1880)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread.access$600(ActivityThread.java:123)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.os.Looper.loop(Looper.java:137)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread.main(ActivityThread.java:4424)
02-14 17:09:00.457: E/AndroidRuntime(692): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 17:09:00.457: E/AndroidRuntime(692): at java.lang.reflect.Method.invoke(Method.java:511)
02-14 17:09:00.457: E/AndroidRuntime(692): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
02-14 17:09:00.457: E/AndroidRuntime(692): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
02-14 17:09:00.457: E/AndroidRuntime(692): at dalvik.system.NativeStart.main(Native Method)
02-14 17:09:00.457: E/AndroidRuntime(692): Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ui.LoginUI
02-14 17:09:00.457: E/AndroidRuntime(692): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
02-14 17:09:00.457: E/AndroidRuntime(692): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
02-14 17:09:00.457: E/AndroidRuntime(692): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
02-14 17:09:00.457: E/AndroidRuntime(692): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1871)
02-14 17:09:00.457: E/AndroidRuntime(692): ... 11 more

The classes polito.mailandroid.ui.ui.LoginUI and polito.mailandroid.ui.ElementProvider were not found. You should check the .apk and your build script to include them.

Its class Not found exception.
make sure class you are using is exists or not and do entry in manifest of particular activity.

The error is
02-14 17:00:46.727: E/AndroidRuntime(644): Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
Have you forgotten to declare your ContentProvider in AndroidManifest.xml?

You are facing a RuntimeException that was not handled. It is Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider because most probably you did not define it in the Manifest file

Your are facing this error please see to it
02-14 16:45:46.487: E/AndroidRuntime(562): java.lang.RuntimeException: Unable to get provider polito.mailandroid.ui.ElementProvider: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider

It seems ur new to java . Read about Exception in java that will help .And for the time being look for error which contains the name of the package or file and read the Caused By error .

i.e error from the Logcat
Caused by: java.lang.ClassNotFoundException: polito.mailandroid.ui.ElementProvider
02-14 16:45:46.487: E/AndroidRuntime(562): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)

Application stops with message like "Unfortunately Soduku has Stopped"

I am totally new to Android . I am using the book Hello, Android. I have created a button for "about" that displays information about the sudoku game. But as soon as i click it, the application stops saying "Unfortunately sudoku has stopped".
02-22 09:27:27.693: E/AndroidRuntime(554): FATAL EXCEPTION: main 02-22 09:27:27.693: E/AndroidRuntime(554): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.example.sudoku/org.example.sudoku.About}: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread.access$600(ActivityThread.java:123) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.os.Handler.dispatchMessage(Handler.java:99) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.os.Looper.loop(Looper.java:137) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread.main(ActivityThread.java:4424) 02-22 09:27:27.693: E/AndroidRuntime(554): at java.lang.reflect.Method.invokeNative(Native Method) 02-22 09:27:27.693: E/AndroidRuntime(554): at java.lang.reflect.Method.invoke(Method.java:511) 02-22 09:27:27.693: E/AndroidRuntime(554): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 02-22 09:27:27.693: E/AndroidRuntime(554): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 02-22 09:27:27.693: E/AndroidRuntime(554): at dalvik.system.NativeStart.main(Native Method) 02-22 09:27:27.693: E/AndroidRuntime(554): Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:691) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.inflate(LayoutInflater.java:466) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.inflate(LayoutInflater.java:396) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.inflate(LayoutInflater.java:352) 02-22 09:27:27.693: E/AndroidRuntime(554): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:251) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.Activity.setContentView(Activity.java:1835) 02-22 09:27:27.693: E/AndroidRuntime(554): at org.example.sudoku.About.onCreate(About.java:9) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.Activity.performCreate(Activity.java:4465) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 02-22 09:27:27.693: E/AndroidRuntime(554): ... 11 more 02-22 09:27:27.693: E/AndroidRuntime(554): Caused by: java.lang.ClassNotFoundException: android.view.scrollview 02-22 09:27:27.693: E/AndroidRuntime(554): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61) 02-22 09:27:27.693: E/AndroidRuntime(554): at java.lang.ClassLoader.loadClass(ClassLoader.java:501) 02-22 09:27:27.693: E/AndroidRuntime(554): at java.lang.ClassLoader.loadClass(ClassLoader.java:461) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.createView(LayoutInflater.java:552) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:636) 02-22 09:27:27.693: E/AndroidRuntime(554): at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:653) 02-22 09:27:27.693: E/AndroidRuntime(554): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678) 02-22 09:27:27.693: E/AndroidRuntime(554): ... 20 more 02-22 09:30:52.675: E/AndroidRuntime(582): FATAL EXCEPTION: main 02-22 09:30:52.675: E/AndroidRuntime(582): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.example.sudoku/org.example.sudoku.About}: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread.access$600(ActivityThread.java:123) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.os.Handler.dispatchMessage(Handler.java:99) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.os.Looper.loop(Looper.java:137) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread.main(ActivityThread.java:4424) 02-22 09:30:52.675: E/AndroidRuntime(582): at java.lang.reflect.Method.invokeNative(Native Method) 02-22 09:30:52.675: E/AndroidRuntime(582): at java.lang.reflect.Method.invoke(Method.java:511) 02-22 09:30:52.675: E/AndroidRuntime(582): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 02-22 09:30:52.675: E/AndroidRuntime(582): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 02-22 09:30:52.675: E/AndroidRuntime(582): at dalvik.system.NativeStart.main(Native Method) 02-22 09:30:52.675: E/AndroidRuntime(582): Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:691) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.inflate(LayoutInflater.java:466) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.inflate(LayoutInflater.java:396) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.inflate(LayoutInflater.java:352) 02-22 09:30:52.675: E/AndroidRuntime(582): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:251) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.Activity.setContentView(Activity.java:1835) 02-22 09:30:52.675: E/AndroidRuntime(582): at org.example.sudoku.About.onCreate(About.java:9) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.Activity.performCreate(Activity.java:4465) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 02-22 09:30:52.675: E/AndroidRuntime(582): ... 11 more 02-22 09:30:52.675: E/AndroidRuntime(582): Caused by: java.lang.ClassNotFoundException: android.view.scrollview 02-22 09:30:52.675: E/AndroidRuntime(582): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61) 02-22 09:30:52.675: E/AndroidRuntime(582): at java.lang.ClassLoader.loadClass(ClassLoader.java:501) 02-22 09:30:52.675: E/AndroidRuntime(582): at java.lang.ClassLoader.loadClass(ClassLoader.java:461) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.createView(LayoutInflater.java:552) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:636) 02-22 09:30:52.675: E/AndroidRuntime(582): at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:653) 02-22 09:30:52.675: E/AndroidRuntime(582): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678) 02-22 09:30:52.675: E/AndroidRuntime(582): ... 20 more 02-22 09:35:04.594: E/AndroidRuntime(596): FATAL EXCEPTION: main 02-22 09:35:04.594: E/AndroidRuntime(596): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.example.sudoku/org.example.sudoku.About}: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread.access$600(ActivityThread.java:123) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.os.Handler.dispatchMessage(Handler.java:99) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.os.Looper.loop(Looper.java:137) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread.main(ActivityThread.java:4424) 02-22 09:35:04.594: E/AndroidRuntime(596): at java.lang.reflect.Method.invokeNative(Native Method) 02-22 09:35:04.594: E/AndroidRuntime(596): at java.lang.reflect.Method.invoke(Method.java:511) 02-22 09:35:04.594: E/AndroidRuntime(596): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 02-22 09:35:04.594: E/AndroidRuntime(596): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 02-22 09:35:04.594: E/AndroidRuntime(596): at dalvik.system.NativeStart.main(Native Method) 02-22 09:35:04.594: E/AndroidRuntime(596): Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:691) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.inflate(LayoutInflater.java:466) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.inflate(LayoutInflater.java:396) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.inflate(LayoutInflater.java:352) 02-22 09:35:04.594: E/AndroidRuntime(596): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:251) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.Activity.setContentView(Activity.java:1835) 02-22 09:35:04.594: E/AndroidRuntime(596): at org.example.sudoku.About.onCreate(About.java:9) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.Activity.performCreate(Activity.java:4465) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 02-22 09:35:04.594: E/AndroidRuntime(596): ... 11 more 02-22 09:35:04.594: E/AndroidRuntime(596): Caused by: java.lang.ClassNotFoundException: android.view.scrollview 02-22 09:35:04.594: E/AndroidRuntime(596): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61) 02-22 09:35:04.594: E/AndroidRuntime(596): at java.lang.ClassLoader.loadClass(ClassLoader.java:501) 02-22 09:35:04.594: E/AndroidRuntime(596): at java.lang.ClassLoader.loadClass(ClassLoader.java:461) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.createView(LayoutInflater.java:552) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:636) 02-22 09:35:04.594: E/AndroidRuntime(596): at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:653) 02-22 09:35:04.594: E/AndroidRuntime(596): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678) 02-22 09:35:04.594: E/AndroidRuntime(596): ... 20 more 02-22 09:43:32.034: E/AndroidRuntime(610): FATAL EXCEPTION: main 02-22 09:43:32.034: E/AndroidRuntime(610): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.example.sudoku/org.example.sudoku.About}: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread.access$600(ActivityThread.java:123) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.os.Handler.dispatchMessage(Handler.java:99) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.os.Looper.loop(Looper.java:137) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread.main(ActivityThread.java:4424) 02-22 09:43:32.034: E/AndroidRuntime(610): at java.lang.reflect.Method.invokeNative(Native Method) 02-22 09:43:32.034: E/AndroidRuntime(610): at java.lang.reflect.Method.invoke(Method.java:511) 02-22 09:43:32.034: E/AndroidRuntime(610): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 02-22 09:43:32.034: E/AndroidRuntime(610): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 02-22 09:43:32.034: E/AndroidRuntime(610): at dalvik.system.NativeStart.main(Native Method) 02-22 09:43:32.034: E/AndroidRuntime(610): Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class scrollview 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:691) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.inflate(LayoutInflater.java:466) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.inflate(LayoutInflater.java:396) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.inflate(LayoutInflater.java:352) 02-22 09:43:32.034: E/AndroidRuntime(610): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:251) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.Activity.setContentView(Activity.java:1835) 02-22 09:43:32.034: E/AndroidRuntime(610): at org.example.sudoku.About.onCreate(About.java:9) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.Activity.performCreate(Activity.java:4465) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 02-22 09:43:32.034: E/AndroidRuntime(610): ... 11 more 02-22 09:43:32.034: E/AndroidRuntime(610): Caused by: java.lang.ClassNotFoundException: android.view.scrollview 02-22 09:43:32.034: E/AndroidRuntime(610): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61) 02-22 09:43:32.034: E/AndroidRuntime(610): at java.lang.ClassLoader.loadClass(ClassLoader.java:501) 02-22 09:43:32.034: E/AndroidRuntime(610): at java.lang.ClassLoader.loadClass(ClassLoader.java:461) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.createView(LayoutInflater.java:552) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:636) 02-22 09:43:32.034: E/AndroidRuntime(610): at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:66) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.onCreateView(LayoutInflater.java:653) 02-22 09:43:32.034: E/AndroidRuntime(610): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678) 02-22 09:43:32.034: E/AndroidRuntime(610): ... 20 more

In about.xml Change scrollview to ScrollView and TextView
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dip" >
<TextView
android:id="#+id/about_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/about_text" />
</ScrollView>

Is the buttons's onclick attribute pointing to an existing method in the activity class?
If you have
android:onClick="somefunction"
in the XML layout,
then you must have:
public void somefunction(View view) {
//do stuff
}
in the activity

Error seeems to be here in these statements : at org.example.sudoku.About.onCreate(About.java:9) 02-22
Line 9 of About.java code...most prob related to setContentView()
Check your xml code that you are setting on, seems to be bug there...
Good option while debuging would be to go step by step, like say removing all your xml code here with single textview layout to see if there is problem or not... and so on....