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POAndroid Fragment null pointer when fetching view
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  1. POAndroid Fragment null pointer when fetching view
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    copied!<p>I have been hitting a wall with Fragments and triggering a view refresh when the adapter changes for a listview inside the fragment. Right now I have:</p> <ul> <li>A main activity which holds the FragmentManager</li> <li>The activity creates fragments based on position through the FragmentPagerAdapter.getItem method</li> <li>A subsequent activity or button press causes the data behind one of the Fragments to change</li> <li>The activity calls the refresh method on the custom Fragment class to trigger the data refresh</li> <li>The refresh method fetches the ListView object in the fragment <ul> <li>This is where the Null exception occurs</li> </ul></li> </ul> <p>The refresh method is below:</p> <pre><code>public void refresh() { groups = new Select() .from(Group.class) .execute(); listView = (ListView)getActivity().findViewById(R.id.overview_container); // Never get here groupAdapter.clear(); groupAdapter.setItems(groups); listView.invalidateViews(); } </code></pre> <p>The setup is</p> <pre><code>public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { view = inflater.inflate(R.layout.fragment_overview, container, false); groups = new Select() .from(Group.class) .execute(); listView = (ListView)view.findViewById(R.id.overview_container); listView.setAdapter(new GroupAdapter(view.getContext(), R.layout.time_view, groups)); return view; } </code></pre> <p>Is there something fundamental I am missing here? Is there an easier pattern here like listeners that can work around this issue? I just can't seem to get the view to return anything but null - even if I store it.</p>
 

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