Question

I’m getting a java.lang.NullPointerException right when the app launches and it shuts down. The error from the emulator is “Unfortunately, appname has stopped”. It was working fine, until I wrote a bunch of new code, and changed the manifest. Hopefully it’s not the manifest, but my question is, how can I find out what line of code is the problem? The trace dump means nothing to me, and even though it’s verbose, having …11 more doesn’t let me see the whole thing.

I don’t really know what that error means. I’ve searched for it, but there seems to be a list of things it could mean. I’ve tried Project>Clean, I’ve tried messing with the manifest again, but I still get the error. I’ve checked/unchecked external libraries. Just done what people have suggested to do for other people getting the same error. So I’d really like to know, what line set it off?

Here is the output if this helps:

06-29 08:37:23.680: E/AndroidRuntime(1225): FATAL EXCEPTION: main
06-29 08:37:23.680: E/AndroidRuntime(1225): java.lang.RuntimeException: Unable to    instantiate activity      ComponentInfo{com.upliftly.android/com.upliftly.android.UpliftlyActivity}: java.lang.NullPointerException
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1879)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1980)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread.access$600(ActivityThread.java:122)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1146)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.os.Looper.loop(Looper.java:137)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread.main(ActivityThread.java:4340)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at java.lang.reflect.Method.invokeNative(Native Method)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at java.lang.reflect.Method.invoke(Method.java:511)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at dalvik.system.NativeStart.main(Native Method)
06-29 08:37:23.680: E/AndroidRuntime(1225): Caused by: java.lang.NullPointerException
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:101)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at com.upliftly.android.UpliftlyActivity.<init>(UpliftlyActivity.java:19)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at java.lang.Class.newInstanceImpl(Native Method)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at java.lang.Class.newInstance(Class.java:1319)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.Instrumentation.newActivity(Instrumentation.java:1023)
06-29 08:37:23.680: E/AndroidRuntime(1225):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1870)
06-29 08:37:23.680: E/AndroidRuntime(1225):     ... 11 more

Answer 1

Usually when you see a stack trace like the one you posted, you should focus in the lines after the last

Caused by: 

line. After that, detect the line that is has your package name and it is (in most cases) that line that caused the exception from your code. In the stack trace that you posted, that line is

at com.upliftly.android.UpliftlyActivity.<init>(UpliftlyActivity.java:19)