Java.lang.IllegalStateException : The application PagerAdapter changed the adapter's contents without calling PagerAdapter#notifyDataSetChanged android 错误

Question

我正在尝试使用静态类将值传递给 View ，而不是使用 intent，因为我必须传递大量数据。有时我会得到这个错误，但找不到主要原因是什么

错误:-

java.lang.IllegalStateException:应用程序的 PagerAdapter 在未调用 PagerAdapter#notifyDataSetChanged 的​​情况下更改了适配器的内容!预期适配器项数:101，找到:200

我的寻呼机类

public class MemeDetailActivity extends AppCompatActivity implements OnDialogClickListner<Void> {
    private ViewPager mPager;
    private List<Datum> mList;
    private ScreenSlidePagerAdapter pagerAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_meme_detail);
        mList = DataResult.getInstance().getData();
        DataResult.getInstance().resetData();
        if (mList != null)
            startPager(selected_position);
        else
            Toast.makeText(this, "Error loading data", Toast.LENGTH_SHORT).show();
        // ATTENTION: This was auto-generated to implement the App Indexing API.
        // See https://g.co/AppIndexing/AndroidStudio for more information.
        client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
    }

    private void startPager(int position) {
        pagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
        mPager.setAdapter(pagerAdapter);
        pagerAdapter.notifyDataSetChanged();
        mPager.setOffscreenPageLimit(0);
        mPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                new Interactors(MemeDetailActivity.this).updateView(Util.getAccessToken(), mList.get(position).getId(), new OnFinishListner<ViewsRM>() {
                    @Override
                    public void onFinished(ViewsRM result) {

                    }

                    @Override
                    public void onFailed(String msg) {
                    }
                });
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
        mPager.setCurrentItem(position);
    }

    public class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter {
        SparseArray<Fragment> registeredFragments = new SparseArray<Fragment>();

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


        //todo entry point 3 : showing the image in the viewpager
        @Override
        public Fragment getItem(int position) {
            Fragment fragment = new fragment_mypager_new();
            Bundle bundle = new Bundle();
            if (frmMyMemes)
                bundle.putParcelable("MY_DATA", myList);
            bundle.putSerializable("DATA", mList.get(position));
            fragment.setArguments(bundle);
            return fragment;
        }

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

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            Fragment fragment = (Fragment) super.instantiateItem(container, position);
            registeredFragments.put(position, fragment);
            return fragment;
        }

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

        public Fragment getRegisteredFragment(int position) {
            return registeredFragments.get(position);
        }
    }

}

我的静态类

public class DataResult<T> {

    private static DataResult instance;
    private List<T> data = null;

    protected DataResult() {

    }

    public static synchronized DataResult getInstance() {
        if (instance == null) {
            instance = new DataResult();
        }
        return instance;
    }

    public List<T> getData() {
        return data;
    }

    public void setData(List<T> data) {
        this.data = data;
    }

    public void resetData() {
        data = null;
    }
}

我如何调用 Activity

    Intent intent = new Intent(getActivity(), MemeDetailActivity.class);
    DataResult.getInstance().setData(mListA);

Answer 1

看看你的代码:

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

此代码用于在 View 更改时刷新 View 。它也被称为 notifyDataSetChanged()

它是可选的 ovverride 方法，因此您可以将其删除。

看看这个答案:ViewPager PagerAdapter not updating the View

否则您可以将 FragmentStatePagerAdapter 更改为 FragmentPagerAdapter