Fragment already added

Question

重点代码如下：一下代码已经完整执行，但是还是报了java.lang.IllegalStateException: Fragment already added重复添加的错误，求大神解决啊！
@Override
    public Object instantiateItem(ViewGroup container, int position) {
//      System.out.println("instantiateItem...............");
        // 得到缓存的fragment
        Fragment fragment = (Fragment) super.instantiateItem(container,
                position);
        // 得到tag
        String fragmentTag = fragment.getTag();
        if (fragmentFlags.get(position % fragmentFlags.size())) {
            System.out.println("进入instantiateItem该方法了");
            FragmentTransaction beginTransaction = fm.beginTransaction();
            // 移除旧的fragment
            beginTransaction.remove(fragment);
            // 换成新的fragment
            fragment = mFragments.get(position);
            // 添加新fragment时必须用前面获得的tag 
            beginTransaction.add(container.getId(), fragment, fragmentTag);
            beginTransaction.attach(fragment);
            beginTransaction.commit();
            //复位更新标志
            fragmentFlags.set(position, false);
        }
        return fragment;
    }

Answer 1

http://blog.csdn.net/leeo1010/article/details/37934987