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copied!<p>When the orientation switches (really whenever Android decides to recreate the <code>Fragment</code>), the existing <code>Fragment</code> is destroyed then recreated. </p> <p>However, when Android recreates your <code>Fragment</code>, it doesn't call your custom <code>newInstance()</code> method. It uses the empty no-args constructor.</p> <p>This means that your <code>Fragment</code> <em>won't</em> have a non-null reference to whatever custom <code>Object</code> you want, resulting in the NPE being thrown.</p> <p>You will need to figure out a way to pass the <code>Object</code>. If the <code>Object</code> is a simple data <code>Object</code> consider passing its fields via the <code>setArguments()</code> method or Serializing it.</p> <pre><code>MyFragment fragment = new MyFragment(); Bundle data = new Bundle(); data.putString ("key_string", "your string here"); fragment.setArguments (data); </code></pre> <p>You could also create an <code>interface</code> that queries the Activity for the Object. For example:</p> <pre><code>public class MyFragment extends Fragment { public interface ObjectProvider { public CustomObject getCustomObject(); } private ObjectProvider provider; @Override public void onAttach (Activity activity) { super.onAttach(activity); try{ provider = (ObjectProvider) activity;//get an instance of the ObjectProvider } catch (ClassCastException e) { e.printStackTrace(); throw new RuntimeException ("This isn't an ObjectProvider."); } } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.layout_fragment, container, false); provider.getCustomObject().getSomething(); return rootView; } } </code></pre> <p>Then your Activity needs to implement the interface:</p> <pre><code>public class MainActivity implements MyFragment.ObjectProvider{ @Override public CustomObject getCustomObject() { return new CustomObject(); } } </code></pre>

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