Question

我有一些带有一些项目的FragmentList。如果我单击某个项目，将打开包含Viewpager的相应片段。到目前为止没问题，但如果我回到List并再次单击该项，则不再调用方法getItem（int position）。
这里有类似问题的链接：
Display fragment viewpager within a fragment

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    view = inflater.inflate(R.layout.activity_fragment_runtime, container, false);
    mViewPager = (ViewPager) view.findViewById(R.id.pager);
    indicator = (TitlePageIndicator) view.findViewById(R.id.indicator);
    MyFragmentPagerAdapter mMyFragmentPagerAdapter = new MyFragmentPagerAdapter(getActivity().getSupportFragmentManager());
    mViewPager.setAdapter(mMyFragmentPagerAdapter);
    indicator.setViewPager(mViewPager);

    return view; 
  }

class MyFragmentPagerAdapter extends FragmentStatePagerAdapter implements TitleProvider {

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

    @Override
    public String getTitle(int position) {

        return muxbusTitles[position];
    }

    @Override
    public Fragment getItem(int location) {

        return muxbusFragmentList.get(location);
    }

    @Override
    public int getCount() {

        return muxbusTitles.length;
    }

}

    return view;

}

修改如果有人感兴趣，解决方案是从PagerAdapter扩展而不是FragmentStatePagerAdpater，因为Viewpager已经在片段中了。

Answer 1

我确实遇到过类似的问题，经过一段时间的努力，我做了一个自己的理解（假设），ViewPager保留了子片段的引用进入内存甚至托管的Fragment or Activity都被销毁（没有使用Activity测试）。所以我写了这个方法freeFragmentsFromViewPager()。您需要从onDestroy()的{{1}}拨打电话。

Fragment

这是我的适配器代码

     /**
     * This method free the child fragments from ViewPager as ViewPager keeps the reference
     * of child fragments into memory and next time when you again come to visit view pager it won't show the fragment layout
     * because it has the reference to the fragment whilst the fragment's view was already destroyed.
     */
    private void freeFragmentsFromViewPager()
    {
        for(int i = 0; i < TabsFragmentPagerAdapter.fragments.length; i++)
        {
            Fragment fragment = TabsFragmentPagerAdapter.fragments[i];

            if(fragment != null)
            {
                FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();  
                fragmentTransaction.remove(fragment);
                fragmentTransaction.commit();

                TabsFragmentPagerAdapter.fragments[i] = null;
            }       
        }   
    }

Viewpager + FragmentStatePagerAdapter + Fragment无法正常工作

1 个答案: