问如何使用Activity页面代替Fragment进行Android页面刷屏？

EN

private void initialisePaging() {
    // TODO Auto-generated method stub
    List<Fragment> fragments = new Vector<Fragment>();

    fragments.add(Fragment.instantiate(this, AboutFragment.class.getName()));
    fragments.add(Fragment.instantiate(this, ServiceFragment.class.getName()));
    fragments.add(Fragment.instantiate(this,ProcessFragment.class.getName()));
    mPagerAdapter =new PagerAdapter(this.getSupportFragmentManager(), fragments);

    ViewPager pager = (ViewPager) findViewById(R.id.viewpager);
    pager.setAdapter(mPagerAdapter);

}

List<ActionBarActivity> ac=new Vector<ActionBarActivity>();
ac.add(ActionBarActivity.INPUT_SERVICE(this, AboutActivity.class.getName()));
ViewPager pager = (ViewPager) findViewById(R.id.viewpager);
pager.setAdapter(mPagerAdapter);