调用notifyDataSetChanged

Question

我正在尝试使用FragmentPagerAdapter更新视图分页程序。每次我从适配器调用notifyDataSetChanged时，都会得到一个force close，并显示此错误"java.lang.IllegalStateException: Recursive entry to executePendingTransactions".

任何关于这方面的建议都将是有帮助的，我已经在下面发布了代码，我将在此之后发布2个链接，指向我在这个主题上的其他2个问题。更新这个ViewPager让我很头疼，所以任何建议都将不胜感激。

Removing Tabs using FragmentPagerAdapter，https://stackoverflow.com/questions/32834861/adding-and-removing-tabs-using-fragmentpageradapter

public void setTabsToSHow() {

    Toast.makeText(getActivity(), Integer.toString(listOfTitles.size()), Toast.LENGTH_LONG).show();

    mViewPager.getAdapter().notifyDataSetChanged();
}






class TabPageAdapter extends FragmentPagerAdapter {

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

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        return super.instantiateItem(container, position);

    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        super.destroyItem(container, position, object);
    }

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case JudgeActivity.JUDGE_MAIN:
                if (mMainFragment == null) {
                    mMainFragment = JudgeMainFragment.newInstance();
                }
                return mMainFragment;
            case JudgeActivity.JUDGE_VERDICTS:
                if (mVerdictFragment == null) {
                    mVerdictFragment = JudgeVerdictFragment.newInstance();
                }
                return mVerdictFragment;
            case JudgeActivity.JUDGE_CLASSIFY:
                if (mClassifyFragment == null) {
                    mClassifyFragment = JudgeClassifyFragment.newInstance();
                }
                return mClassifyFragment;
            case JudgeActivity.JUDGE_SIDEBAR:
                if (mSidebarFragment == null) {
                    mSidebarFragment = JudgeSidebarFragment.newInstance((SidebarCall) mActivity);
                }
                return mSidebarFragment;
        }
        return null;
    }

    @Override
    public int getCount() {
        return listOfTitles.size();
    }


    @Override
    public int getItemPosition(Object object) {
        Toast.makeText(getActivity(), "itempostioton",Toast.LENGTH_SHORT).show();
        return POSITION_NONE ;
    }


    @Override
    public CharSequence getPageTitle(int position) {
    //  return CONTENT[position % CONTENT.length].toUpperCase(Locale.US);

        //Notify data set changed can only be called from inside this class
        notifyDataSetChanged();
        return listOfTitles.get(position);
    }








}

Answer 1

从public CharSequence getPageTitle(int position)方法中移除notifyDataSetChanged();

其次，不要从case语句返回，而是对局部变量进行赋值，最后返回片段。在每个case块之后使用break。