Fragment is null whenever trying to reload fragment after a delete

Question

I have a list in a table fragment with delete button in each row.Whenever I tap to delete I am getting

java.lang.NullPointerException: Attempt to write to field 'int android.support.v4.app.Fragment.mNextAnim' on a null object reference

I have used this code example to reload the page. And I found that my fragment is null. I don't know how to resolve this issue. Also how to change it to support.v4.app or simply FragmentManager.

This is my code

   Fragment frg = null;           
    frg = getFragmentManager().findFragmentById(R.id.table_fragment_container);
    Log.v("frag",""+frg);  //this is null 
final FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.detach(frg);
ft.attach(frg); 
ft.commit();

you can call notifyDatasetChanged() on list – Sanjeet Oct 21 '16 at 06:37 — Sanjeet, Oct 21 '16 at 06:37
better if you provide your code for us to review as well. – cipley Oct 21 '16 at 06:43 — cipley, Oct 21 '16 at 06:43

score 0 · Answer 1 · edited Oct 21 '16 at 07:13

0

I think you did not set "Your_Fragment_TAG" tag in onCreateView() of your fragment, please check. Or you can use below code for fragment reloading.

Fragment currentFragment = getActivity().getFragmentManager().findFragmentById(your_fragment_container);

if (currentFragment instanceof "fragment_layout_instance") {

FragmentTransaction fragTransaction =   (getActivity()).getFragmentManager().beginTransaction();
     fragTransaction.detach(currentFragment);
     fragTransaction.attach(currentFragment);
     fragTransaction.commit();

}

}

edited Oct 21 '16 at 07:13

musica

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answered Oct 21 '16 at 06:47

EKN

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getting error in this line if (currentFragment instanceof "fragment_layout_instance") – Elizabeth Oct 21 '16 at 07:32

score 0 · Answer 2 · answered Oct 21 '16 at 07:37

0

Create an object of your fragment and replace "fragment_layout_instance" with you fragment object.

answered Oct 21 '16 at 07:37

EKN

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1
16
29

Like this ri8 TableViewFragment mTableViewFragment = new TableViewFragment(); and replaced if (currentFragment instanceof mTableViewFragment ) {} but still error – Elizabeth Oct 21 '16 at 07:47

score 0 · Accepted Answer · answered Oct 21 '16 at 08:09

I solved this by adding TAG

Fragment frg = null;
 frg = getFragmentManager().findFragmentByTag("tabFrag");                                                       
final FragmentTransaction ft = getFragmentManager().beginTransaction();   
ft.detach(frg);
ft.attach(frg);
ft.commit();

and while calling this fragment i added TAG

fragmentTransaction.replace(R.id.RLfragment_container, mTableViewFragment, "tabFrag");

Fragment is null whenever trying to reload fragment after a delete

3 Answers3