java.lang.IllegalStateException: Fragment already active at View Pager

Question

I am writing an application where I using PageViewer to show infinite client using solution available here.

In my case I have to update this already added child from other event say from [onPageState][2], using following code:

PageFragment  scr = (PageFragment) mPagerAdapter.getItem(mPager.getCurrentItem());

but it returning IllegalStateException that say, Fragment already Active.

I checked with this but I am not getting it.

EDIT: Fragment child add code: It's at very beginning, I create first list of fragment:

for (int i = 0; i < 5 ; i++) {
            PageFragment fragment = new PageFragment();
            Bundle bundle = new Bundle();
            bundle.putInt("page", i);
            fragment.setArguments(bundle);
            pageList.add(fragment);
        }

EDIT2: Here the line fragment.setArguments(..) causing error, why?

and this is adapter implementation:

private class PagerAdapter extends FragmentStatePagerAdapter {

        public PagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            int _pos = position % 5;

            PageFragment fragment = pageList.get(_pos);
            Bundle bundle = new Bundle();
            bundle.putInt("page", position);
            fragment.setArguments(bundle);

            return fragment;
        }

        @Override
        public int getCount() {
            return MAX_CARD_PAGES;
        }
    }

Any suggestion.