CODEWITHSUNDEEP
androidandroid-viewpager
Nguyen Minh Binh
Nguyen Minh Binh

Reputation: 24443

How to reset viewpager content on Android?

Please tell me how to reset the content of ViewPager on android. I tried to call adapter.notifyDataSetChanged() but the adapter doesn't call getItem(position) when I scroll the view. It always returns old child views.

Update: This is my Fragment View. When I reset viewPager data, It used loaded Fragment views. It's just start at the onCreateView instead of Constructor. 

public class ResultView extends Fragment {
//Declare properties

     //Constructor 
public ResultView(Province province, Calendar calendar) {
    Log.d("xskt", "ResultView constructor");
    this.province = province;
    this.calendar = (Calendar) calendar.clone();
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    Log.d("xskt", "ResultView onCreateView");
    View view = inflater.inflate(R.layout.resultview, null);

    //do some thing

    return view;
}

Thanks.

Upvotes: 6

Views: 15446

Answers (4)

Nicole Vukadinova
Nicole Vukadinova

Reputation: 1

It works if you do the following:

  • invalidate the viewPager to invalidate the cache
  • call notifyDataSetChanged() to tell the adapter that there have been changes and it has to refresh the Fragments
  • override getItemPosition in your FragmentStatePagerAdapter in order to have all of your Fragments refreshed

In your Activity or wherever you want to refresh the data:

viewPager.invalidate();
fragmentStatePageAdapter.notifyDataSetChanged();

In you FragmentStatePageAdapter:

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

Upvotes: 0

Hadi Note
Hadi Note

Reputation: 1415

I think the best solution to reload fragments in another fragment is :

@Override
public void onPause() {
    super.onResume();
    List<Fragment> fragments = getFragmentManager().getFragments();
    if (fragments != null) {
        FragmentTransaction fragmentTransaction  = getFragmentManager().beginTransaction();
        for (Fragment fragment : fragments) {
            if (fragment instanceof Fragment) {
                fragmentTransaction.remove(fragment);
            }
        }
        fragmentTransaction.commitNowAllowingStateLoss();
    }
}

Check for your use case whether commitNowAllowingStateLoss or commitAllowingStateLoss is necessary.

Upvotes: 2

Nguyen Minh Binh
Nguyen Minh Binh

Reputation: 24443

I have changed to use FragmentStatePagerAdapter instead of FragmentPagerAdapter, the problem is resolved. Hope this helps.

Upvotes: 39

Patrick Jackson
Patrick Jackson

Reputation: 19446

One method is to use the observer pattern. The data you are presenting is likely in an sqlite DB (or in stored in memory). You can set a listener in your fragment that will make the necessary updates to your fragment when the data is changed.

Upvotes: 0

Related Questions