Dialog Dialog Modify Drops Using getActivity ()

I'm currently having issues with DialogFragments. I use the latest support packages v.4 (option 8, I think) My problem is that if the orientation of my phone changes when the dialog is open, the application starts acting strange.

Currently my application works as follows: There is a FragmentActivity, it calls a fragment. This snippet then calls DialogFragment (via getActivity (). GetSupportFragmentManager ().

If the orientation changes when the dialog opens, getActivity () at Fragment = null. This causes a problem if I want to end an Activity, etc.

To call this, you open a dialog box, change the orientation and click the button. Only after pressing the button does the crash

My DialogFragment is called AlertDialogFragment:

public class AlertDialogFragment extends DialogFragment {
private static Builder mBuilder;
private static DialogInterface.OnClickListener mListener;

public static AlertDialogFragment newInstance(Context context, DialogInterface.OnClickListener listener) {
    mBuilder = new AlertDialog.Builder(context);
    mListener = listener;       
    return new AlertDialogFragment();
}

//... some functions to set Icons etc

public void setButton(int whichButton, CharSequence buttonText) {
    final DialogInterface.OnClickListener listener = mListener == null ? null : mListener;      
    mBuilder.setPositiveButton(buttonText, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
                listener.onClick(dialog, whichButton);
            }
    });
}

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    return mBuilder.create();
}
}

This is a snippet:

public class TestBedFragment extends Fragment implements DialogInterface.OnClickListener   {
// onCreateView Stuff  

private void showCrashDialog() {
    FragmentTransaction ft = getActivity().getSupportFragmentManager().beginTransaction();
    AlertDialogFragment newDialog = AlertDialogFragment.newInstance(getActivity(), this);
    newDialog.setTitle("Test");     
    newDialog.setIcon(android.R.drawable.ic_dialog_alert);
    newDialog.setMessage("Testing testing testing... 1, 2, 3... Just press Ok.");
    newDialog.setButton(DialogInterface.BUTTON_POSITIVE, "Ok");
    newDialog.show(ft, "dialog");

    // Cause the problem. Simulate the user turning the screen
    getActivity().setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
    getActivity().setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}

@Override
public void onClick(DialogInterface dialog, int which) {

    /*
     * hexnumber = a hex number
     * Normally equals: TestBedFragment{hexnumber #0 id=hexnumber}
     * With crash equals: TestBedFragment{hexnumber}
     */
    Log.e("TestBedFragment", "this = " + this);

    /*
     * hexnumber = a hex number
     * Normally equals: com.example.TestBed.TestBedActivity@hexnumber
     * With crash equals: null
     */
    Log.e("TestBedFragment", "getActivity() = " + getActivity()); // Will equal null... ???

    getActivity().finish();
}
}

I'm not too sure what causes this? Sorry if this is a stupid question. I read elsewhere about "Windows Leaking", but I did not see any mention of this in logcat.

Can someone help me :) He is really appreciated

thank