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android - App Crashes on AsyncTask Screen Rotation

I'm using AsyncTask in one of the fragments of an activity.

The AsyncTask is working perfectly but on screen rotation, it loses the reference to activity and the variable returns NullPointerException thus the app crashes.

I looked at similar questions like this, this, this, and this, but I don't think using config change hack is the solution.

The code that maybe crashing the application (according to LogCat, the NullPointerException is at the following line):

Context context = MyActivity.this.getApplicationContext();

I've to pass the context in another function residing outside of the activity and fragment class.

Thank you in advance.

Update: My LogCat

09-29 09:40:53.415: E/AndroidRuntime(21997): FATAL EXCEPTION: AsyncTask #2
09-29 09:40:53.415: E/AndroidRuntime(21997): java.lang.RuntimeException: An error occured while executing doInBackground()
09-29 09:40:53.415: E/AndroidRuntime(21997):    at android.os.AsyncTask$3.done(AsyncTask.java:278)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.lang.Thread.run(Thread.java:856)
09-29 09:40:53.415: E/AndroidRuntime(21997): Caused by: java.lang.NullPointerException
09-29 09:40:53.415: E/AndroidRuntime(21997):    at com.example.CommonClasses.CommonFunctions.readFile(CommonFunctions.java:262)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at com.example.CommonClasses.CommonFunctions.readFileContents(CommonFunctions.java:308)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at com.example.android.AvailabilityFragment$AvailabilityData.doInBackground(AvailabilityFragment.java:160)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at com.example.android.AvailabilityFragment$AvailabilityData.doInBackground(AvailabilityFragment.java:1)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at android.os.AsyncTask$2.call(AsyncTask.java:264)
09-29 09:40:53.415: E/AndroidRuntime(21997):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
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Try this way

<activity
    android:name=".ActivityName"
    android:configChanges="orientation|screenSize|keyboardHidden"/>

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