I'm developing an android tablet application and i need to implement screen orientation (landscape and portrait). when screen orientation changes the fragment asyntactask restarting again. (sometimes application crashing) I need to stop restarting the asynctask and request data again. want to load the existing json data in to the new screen. any help appreciate.
approch: android:configChanges="keyboardHidden|orientation|screenSize" is not working because of im using a fragment class.
You may find some hack (including muting the configuration changes or retaining the instance) to somehow get it work, but really AsyncTasks are evil and you should stay as far as you can from it most of the time.
If your current AsyncTask's job is to load some data from the network before showing it inside your Fragment, I'd recommend to use an AsyncTaskLoader. The examples in the javadoc should give you a good idea of how to implement it.
This will allow the network request to keep going while you rotate, to notify the UI (i.e. the LoaderManager.LoaderCallbacks) with the result only when it is ready to process it (so not while rotating for example), and will also cache the result so that you don't re-issue the network request each time you need the data.
There are a bunch of 3rd-party libraries trying to address this very common problem too, and Loaders also have their intricacies, but if I understand your use case correctly it should be just what you need.
Don't forget that whatever solution you choose it will have to account for the rotation (activity destroy / recreate) happening before, during and after the load of the data.