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App crashes when restoring from background

I have static values that are deleted after my application is a long time in the background or after opening many different apps, causing that my app crashes.
I think that Android OS is removing data from my app or "killing" it.
Is there any way to keep my app's data to avoid this problem?
NOTE: I can't save this values on SharedPreferences or in a database because there are many HashMaps and ArrayLists, is too much information.
It is necessary that these values are static because I need them available in many classes o my app in any time.
E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.proyect/com.proyect.gui.ActivityMenu}: java.lang.NullPointerException: println needs a message
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2266)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2316)
at android.app.ActivityThread.access$600(ActivityThread.java:150)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1298)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:213)
at android.app.ActivityThread.main(ActivityThread.java:5225)
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:741)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException: println needs a message
at android.util.Log.println_native(Native Method)
at android.util.Log.v(Log.java:117)
at com.proyect.gui.FragmentMenu.onActivityCreated(FragmentMenu.java:145)
at android.support.v4.app.Fragment.performActivityCreated(Fragment.java:1983)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1092)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1252)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1234)
at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:2046)
at android.support.v4.app.FragmentController.dispatchActivityCreated(FragmentController.java:174)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:597)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1171)
at android.app.Activity.performStart(Activity.java:5143)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2239)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2316) 
at android.app.ActivityThread.access$600(ActivityThread.java:150) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1298) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:213) 
at android.app.ActivityThread.main(ActivityThread.java:5225) 
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:741) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557) 
at dalvik.system.NativeStart.main(Native Method) 

Change this:
Log.v("errorTag", e.getMessage());
To this:
String error = e.getMessage();
if(error == null)
error = "It's crashed here";
Log.v("errorTag", error );
OR SIMPLER
Log.v("errorTag", e );
The point is that e.getMessage() is null. So, always check if e.getMessage() is not null before print it

Trying to add a Facebook Friend Picker, but get null pointer exception

I'm trying to learn and add some basic Facebook functionality to my Android App (an address book). What I'm eventually going to do is import a friends profile picture. I've currently only copy/pasted what I need from the "FriendPickerSample" example project, which is just a button that brings up a friend picker fragment, and, if I remember correctly, it places the names you picked into a list. I've altered it to come up when an imageview is clicked, and it'll just Toast the single name that is chosen. When I try to bring up the friend picker, I get a null pointer exception, and I don't understand why. Here's the log:
FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.JDE.RAB/com.JDE.RAB.PickFriendsActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
at android.app.ActivityThread.access$2300(ActivityThread.java:125)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4627)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.facebook.widget.PickerFragment.onCreateView(PickerFragment.java:152)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:871)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1083)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:635)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1431)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:523)
at com.JDE.RAB.PickFriendsActivity.onStart(PickFriendsActivity.java:112)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1129)
at android.app.Activity.performStart(Activity.java:3781)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2636)
... 11 more
This is the code in my onclick, which is supposed to open the PickFriendsActivity:
if (Session.getActiveSession() == null || Session.getActiveSession().isClosed())
{
Session.openActiveSession(AddNewTabLayoutActivity.this, true, null);
}//endif
FriendPickerApplication application = (FriendPickerApplication) GetMyApplication();
application.setSelectedUsers(null);
Intent intent = new Intent(AddNewTabLayoutActivity.this, PickFriendsActivity.class);
// Note: The following line is optional, as multi-select behavior is the default for
// FriendPickerFragment. It is here to demonstrate how parameters could be passed to the
// friend picker if single-select functionality was desired, or if a different user ID was
// desired (for instance, to see friends of a friend).
//multi-select is OFF
PickFriendsActivity.populateParameters(intent, null, false, true);
Debugger.SendNotification(getApplicationContext(), "Alert", "Alert", "Starting Activity For Result", 3009);
startActivityForResult(intent, 2);
PickFriendsActivity, line 112 is super.onStart(); Should I post the entirety of that activities source code?
Thanks for any help!

You should copy res/layout/pick_friends_activity.xml to your own project too.

NullPointerException in HardwareRenderer

I wish I had more information about this error but I just don't. I have a tool called BugSense(Now it is Splunk MINT) that sends crashes to a remote server and this is all I'm getting:
java.lang.NullPointerException
at android.view.HardwareRenderer$GlRenderer.checkCurrent(HardwareRenderer.java:960)
at android.view.HardwareRenderer$Gl20Renderer.destroyLayers(HardwareRenderer.java:1148)
at android.view.ViewRootImpl.destroyHardwareResources(ViewRootImpl.java:576)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:973)
at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2448)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4482)
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:787)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:554)
at dalvik.system.NativeStart.main(Native Method)
The interesting thing is that all of the error instances came from:
BLU DASH 4.0
They are all rooted
They all had Mobile Net turned off
They all had at least 12 running apps
So... what do you think?
has anyone had a NPE in the HardwareRenderer class?
Could it be a 'root' thing (i.e. an issue with the device being rooted)?
Could it be a 'hardware' thing (i.e. an issue with the BLUE DASH 4.0)

The problem is that the code is using an null object.
MyClass class;
class.doStuff(); // Will throw NullPointerException as class is null
MyClass newClass = new MyClass();
newClass.doStuff(); // Will work as newClass is pointing to an object.
As I do not have the offending code, I cannot help further. I would suggest you include the code at (HardwareRenderer.java:960), and the call route from the stack, as this is what is causing the exception.

Asynctask causing NullPointerException

I have an app on Google play. I got a few error reports from the developer page and It's quite hard to figure out the problem.
This is what I have:
java.lang.NullPointerException
at com.seb.example.free.MainActivity$ApplyFilter.onPostExecute(MainActivity.java:828)
at com.seb.example.free.MainActivity$ApplyFilter.onPostExecute(v.java: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:153)
at android.app.ActivityThread.main(ActivityThread.java:4987)
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:821)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
at dalvik.system.NativeStart.main(Native Method)
As you can see I have an asynctask innerclass and the error seems to be in on postexecute.
I have checked my project in eclipse and, as the stacktrace says, the error is on line 828:
(iV.getVisibility() == ImageView.INVISIBLE)
My imageView, iV, is declared as private in MainActivity and I initiate it in oncreate.
I can't reproduce the problem on the three of my phones as i have tested on, so it's quite hard to understand what's causing it.
Anyone who has any ideas? Thanks!

I think that imageview object is becomes null in some where in your code..check whether it initialized or not..and if initialized check where it is used in your project.

It might have been derefferenced in some other place, initialize in onresume and see whether this persists or not.

please check have you initialized iv
try:
if(iv != null)
(iV.getVisibility() == View.INVISIBLE)
else
Log.e("CHECK","iv Null");
if you have not initialized iv then do that first.

android newbie question null pointer on ArrayAdapter.setAdapter

I have been slowing learning and building my first android app. I'm VERY new to java but have already done a couple of projects in C#, VB.NET (back in the day), Objective-C (have 6 apps in the store) and Fortran (waaaaaaaaaaaaaaaaaaaay back in the day ;)
So I just received from overseas a htc legend (I'm not in the US), which i bought in order to have a decent mid-level device for development (it's running non-rooted adnroid 2.1)
The application I have been developing is target level 4 (android 1.6). It uses a 5 Mb sqlite3 database with a .mp3 extension to avoid compression within the apk and proper copying from assets to system folder.
It all works fine on the emulator, and on the device I see that the file size of the app after copying the database matches exactly what I see on the emulator.
now, on my main activity with a list view and a spinner, I bind some data through two array adapters. when running on the device all does smoothly. but when trying to run on the device this part of the code:
public class mainAct extends Activity implements OnItemSelectedListener, TextWatcher, OnItemClickListener
{
/** members */
//private EditText searchtext;
private ListView designations;
private ArrayAdapter<String> adapterShapes;
private ArrayAdapter<String> adapterTypes;
private Spinner types;
.
.
.
public void onCreate(Bundle savedInstanceState)
{
.
.
.
// DESIGNATIONS
//
adapterShapes = new ArrayAdapter<String>(this,R.layout.list_item,shapes); // custom TextView Adapter
designations=(ListView)findViewById(R.id.designations);
Log.e("MAIN.ACCT", "ok to 172");
designations.setAdapter(adapterShapes);
Log.e("MAIN.ACCT", "ok to 174");
designations.setOnItemClickListener(this);
// TYPES
//
adapterTypes=new ArrayAdapter<String>(this,R.layout.spinner_item,DT.get().typesInLibrary);
types=(Spinner)findViewById(R.id.types);
types.setAdapter(adapterTypes);
types.setOnItemSelectedListener(this);
.
.
.
}
}
Both designations.setAdapter(adapterShapes);
& types.setAdapter(adapterTypes);
give me a Null Pointer exception.
I'm using eclipse under mac, the LogCat window throws:
06-25 18:41:37.842:
ERROR/AndroidRuntime(9523): Uncaught
handler: thread main exiting due to
uncaught exception
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523):
java.lang.RuntimeException: Unable to
start activity
ComponentInfo{com.davidhomes.steel/com.davidhomes.steel.mainAct}:
java.lang.NullPointerException
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2596)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2621)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread.access$2200(ActivityThread.java:126)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:1932)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.os.Handler.dispatchMessage(Handler.java:99)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.os.Looper.loop(Looper.java:123)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread.main(ActivityThread.java:4595)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
java.lang.reflect.Method.invokeNative(Native
Method)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
java.lang.reflect.Method.invoke(Method.java:521)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
dalvik.system.NativeStart.main(Native
Method)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): Caused by:
java.lang.NullPointerException
-------------------------------------------------------------- 06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
com.davidhomes.steel.mainAct.onCreate(mainAct.java:183)
--------------------------------------------------------------
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2544)
06-25 18:41:37.891:
ERROR/AndroidRuntime(9523): ... 11
more
06-25 18:46:38.252:
ERROR/ActivityManager(99): fail to set
top app changed!
Line 183 is the first setAdapter call (designations.setAdapter(adapterShapes);), when I comment it out the second setAdapter is the one breaking code
I'm a little lost here, the adapters show the proper number of items on the log window when running from the simulator and the device.
I admit to being a noob to both java and android, so any help is highly appreciated.
regards
david

Well, as you've probably figured out yourself, some variable is null. Unfortunately, there is no obvious source of the NullPointerException in your code.
Therefore, you should first try to identify what variable is null, and hence causing the exception.
For example, findViewById returns null if it cannot find the view, so you may want to double check your ListView and Spinner are being initialised properly.
Of course, the problem may be with your ArrayAdapters, so you should also check them, but from your question it sounds as if you've already done that.
Once you (and we) know exactly where the NullPointerException is occurring, it will be easier to give more specific advice

Oops! it was my fault all along, somehow I had TWO layouts (one for different resolutions), the one being used on my device did not have the proper ListView and Spinner ID. That alternative layout was collapse into a folder and I just forgot about it (I had paused development of the app for about 2 month until I actually got a device to test on).
the one working fine was installing on the simulator but not on the device and vice-versa, weird as the good one matches the resolution of my device (I'm pretty sure I'm also missing something there but that's not important right now)
Still, thanks Chris for pointing me to looking at the Null return value on findViewById. Being new to android I was lost as to were to begin
Best regards
david

I know this is a long closed subject. However I just came across the same problem and this post did not answer it.
What i did, was very silly. I forgot to add a reference to the xml. ie. setContentView(R.layout.settings);
it actually looks like the original post might have also forgotten this so i thought I would just post it.
Cheers.

I had the same problem. I put Log.d messages in printing out every object. It turned out that my ListView object was "null". The reason for this was I had the wrong XML activity listed in my SetContentView. I think the easiest way to debug this problem is keep putting in Log.d messages until you find the object/variable that is "null".