解决Fragment在Viepager中切换不保存状态的问题

在FragmentPagerAdapter中重写以下方法:

         @Override
         public Object instantiateItem(ViewGroup container, int position) {
             Fragment fragment = (Fragment) super.instantiateItem(container, position);
             fm.beginTransaction().show(fragment).commit();

             return fragment;
         }

         @Override
         public void destroyItem(ViewGroup container, int position, Object object) {
             Fragment fragment = (Fragment) object;
             fm.beginTransaction().hide(fragment).commit();
         }