view, adapter, getActivity(), in fragment are all null

Question

In my activity, I call a method which is inside of a fragment to update a ListView in the fragment. However, the getActivity() method returns null, the listView is null, the adapter is null too. But I can see the listView is being displayed. Why are they null?

Note: I call FragmentPagerAdapter.getItem(position) to get the fragment. However, it will return a different instance. According to here, I can reuse the fragment by findFragmentByTag.

It looks like you're having two instances of your fragment type — gunar, Mar 13 '14 at 15:56
I am using `fragmentPagerAdapter` in my activity, and using `adapter.getItem(position)` to get the fragment. So, it might lead to a different instance? @gunar — ZhangLei, Mar 13 '14 at 16:41

score 0 · Answer 1 · answered Mar 13 '14 at 15:56

0

It depends when you try to access your activity and listview. In Fragment's constructor all of these are not available since they are not built yet.

Activity is available after onActivityCreated() callback is triggered
ListView is available after onViewCreated() callback is triggered

answered Mar 13 '14 at 15:56

Pavel Dudka

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Thank you for reply, but my `ListView` is visible when I check if they are null. – ZhangLei Mar 13 '14 at 16:36

view, adapter, getActivity(), in fragment are all null

1 Answers1