Question

我有一个程序，它有片段作为arraylist，我正在使用它与TabLayout，因为我删除一个选项卡我也想删除片段。但是我的实现并不顺序。标签1将删除Fragment2等。请检查我哪里出错？

在onCreate of MainActivity下，这就是我添加片段的方式

     private TabPagerAdapter pagerAdapter;


    public List<Fragment> fragmentList = new ArrayList<>();
     protected void onCreate(Bundle savedInstanceState) {

           fragmentList.add(NewsFragment.newInstance(Tab1));
            fragmentList.add(NewsFragment.newInstance(Tab2));
            fragmentList.add(NewsFragment.newInstance(Tab3));

  mViewPager = (ViewPager) findViewById(R.id.pager);

        pagerAdapter = new TabPagerAdapter(getSupportFragmentManager(), fragmentList);
        mViewPager.setAdapter(pagerAdapter);

这是我的FragmentStatePagerAdapter，removeFragment是我试图删除片段的地方

public class TabPagerAdapter extends FragmentStatePagerAdapter {


    private List<Fragment> mFragmentList;
    private List<String> tabTitles = new ArrayList<>();


    @Override
    public int getItemPosition(Object object) {
        return PagerAdapter.POSITION_NONE;
    }

    @Override
    public Fragment getItem(int position) {

        return mFragmentList.get(position);
    }

    public TabPagerAdapter(FragmentManager fm, List<Fragment> fragmentList) {
        super(fm);
        mFragmentList = fragmentList;
    }

    @Override
    public int getCount() {

        return mFragmentList.size();
    }

    public void removeFragment(int tabPosition) {

        if (!mFragmentList.isEmpty()) {
            mFragmentList.remove(tabPosition);

        }
    }

}

主要活动下的OnActivity结果是我试图删除选项卡＆amp;片段

 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != RESULT_OK || data == null)
            return;
        settingList = (ArrayList<SettingCheckBox>) data.getSerializableExtra(SETTING_CHECK_BOX);
        for (int i = 0; i < settingList.size(); i++) {
            if (settingList.get(i).getChecked()) {
                Log.d("**Checked Item**", String.valueOf(settingList.get(i).getDescription()));

                String removeTab = String.valueOf(settingList.get(i).getDescription());
                Boolean checkedValue = settingList.get(i).getChecked();


                if (removeTab.equals("tab1")) {
                 //remove tab
                        tabLayout.removeTab(tab1);
                        //remove fragment 
                 pagerAdapter.removeFragment(0);
                       // fragmentList.remove(i);
                        pagerAdapter.notifyDataSetChanged();


                } else if (removeTab.equals("tab2")) {

                        tabLayout.removeTab(tab2);
                                 pagerAdapter.removeFragment(1);
                      //  fragmentList.remove(i);

                        pagerAdapter.notifyDataSetChanged();


                } else if (removeTab.equals("tab3")) {

                        tabLayout.removeTab(tab3);
                        pagerAdapter.removeFragment(2);
                     //   fragmentList.remove(i);

                        pagerAdapter.notifyDataSetChanged();
                    }

Answer 1

更改您pagerAdapter.removeFragment(mViewPager.getCurrentItem()); to pagerAdapter.removeFragment(correctFragmentPosition);

correctFragmentPosition =根据removeTab

的值计算

Answer 2

回答我自己的问题。我以这种方式添加了片段

public List<Fragment> fragmentList = new ArrayList<>(); 
private NewsFragment frag1 
frag1 = NewsFragment.newInstance("https://www.yahoo.com");                  
fragmentList.add(frag1);

如果我需要找到片段的位置

for (int i = 0; i < fragmentList.size(); i++) { 
if (fragmentList.get(i).equals(frag1)) {
//found the position so removing it 
pagerAdapter.removeFragment(i); } 
}

无法从其arraylist

2 个答案: