调用 notifyDataSetChanged

Question

我正在尝试使用 FragmentPagerAdapter 更新视图寻呼机。每次我从我的适配器调用 notifyDataSetChanged 时，我都会强制关闭此错误"java.lang.IllegalStateException: Recursive entry to executePendingTransactions".

对此的任何指示都会有所帮助，我在下面发布了代码，并且在此之后我将发布 2 个链接，指向我在此主题上遇到的其他 2 个问题。更新这个 ViewPager 让我非常头疼，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) 方法中删除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。