AdWhirl causing java.lang.NullPointerException after shutdown network

Question

I use AdWhirl and Admob in one of my app,after release, we get a lot of error from adwhirl,and It's reproduce easily like this:

After ad appear,I shutdown wifi,and wait ad timeout,then press back button to exit application.

then the bug appear.the src can download from this.and the exception is like this:

 05-17 11:00:13.265: E/AndroidRuntime(12482): java.lang.RuntimeException: Unable to destroy activity {me.test.admob/me.test.admob.AdWhirlTestActivity}: java.lang.NullPointerException
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3112)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3130)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread.access$1200(ActivityThread.java:123)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1180)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.os.Handler.dispatchMessage(Handler.java:99)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.os.Looper.loop(Looper.java:137)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread.main(ActivityThread.java:4424)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at java.lang.reflect.Method.invokeNative(Native Method)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at java.lang.reflect.Method.invoke(Method.java:511)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at dalvik.system.NativeStart.main(Native Method)
05-17 11:00:13.265: E/AndroidRuntime(12482): Caused by: java.lang.NullPointerException
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.webkit.WebView.requestFocus(WebView.java:7650)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2110)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.onRequestFocusInDescendants(ViewGroup.java:2154)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.requestFocus(ViewGroup.java:2113)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.View.requestFocus(View.java:5323)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewRootImpl.clearChildFocus(ViewRootImpl.java:2200)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.clearChildFocus(ViewGroup.java:669)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.clearChildFocus(ViewGroup.java:669)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.clearChildFocus(ViewGroup.java:669)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.clearChildFocus(ViewGroup.java:669)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.clearChildFocus(ViewGroup.java:669)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.removeViewInternal(ViewGroup.java:3591)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.removeViewInternal(ViewGroup.java:3561)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.view.ViewGroup.removeView(ViewGroup.java:3509)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:998)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1080)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1062)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.support.v4.app.FragmentManagerImpl.dispatchDestroy(FragmentManager.java:1843)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.support.v4.app.FragmentActivity.onDestroy(FragmentActivity.java:314)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.Activity.performDestroy(Activity.java:4629)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1079)
05-17 11:00:13.265: E/AndroidRuntime(12482):    at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3099)
05-17 11:00:13.265: E/AndroidRuntime(12482):    ... 11 more

After my test,I find this exception only appears when use adwhirl with ListFragment in ViewPager.,if I only use in ListFragment or use Fragment in ViewPager,It's work normally. But i still want to know what's wrong,and how can I solve this exception.

Any answer will be appreciate.

Answer 1

1. make sure you handle AdWhirl in your onDestory() Method
2. use a try catch to catch the NullPointer, contact the devlopers and hope that they will fix this (if it is a bug)