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    <p>I want to offer an alternate solution for perhaps a slightly different case, since many of my searches for answers kept leading me to this thread.</p> <p><strong>My case</strong> - I'm creating/adding pages dynamically and sliding them into a ViewPager, but when rotated (onConfigurationChange) I end up with a new page because of course OnCreate is called again. But I want to keep reference to all the pages that were created prior to the rotation.</p> <p><strong>Problem</strong> - I don't have unique identifiers for each fragment I create, so the only way to reference was to somehow store references in an Array to be restored after the rotation/configuration change.</p> <p><strong>Workaround</strong> - The key concept was to have the Activity (which displays the Fragments) also manage the array of references to existing Fragments, since this activity can utilize Bundles in onSaveInstanceState</p> <pre><code>public class MainActivity extends FragmentActivity </code></pre> <p>So within this Activity, I declare a private member to track the open pages</p> <pre><code>private List&lt;Fragment&gt; retainedPages = new ArrayList&lt;Fragment&gt;(); </code></pre> <p>This is updated everytime onSaveInstanceState is called and restored in onCreate</p> <pre><code>@Override protected void onSaveInstanceState(Bundle outState) { retainedPages = _adapter.exportList(); outState.putSerializable("retainedPages", (Serializable) retainedPages); super.onSaveInstanceState(outState); } </code></pre> <p>...so once it's stored, it can be retrieved...</p> <pre><code>@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); if (savedInstanceState != null) { retainedPages = (List&lt;Fragment&gt;) savedInstanceState.getSerializable("retainedPages"); } _mViewPager = (CustomViewPager) findViewById(R.id.viewPager); _adapter = new ViewPagerAdapter(getApplicationContext(), getSupportFragmentManager()); if (retainedPages.size() &gt; 0) { _adapter.importList(retainedPages); } _mViewPager.setAdapter(_adapter); _mViewPager.setCurrentItem(_adapter.getCount()-1); } </code></pre> <p>These were the necessary changes to the main activity, and so I needed the members and methods within my FragmentPagerAdapter for this to work, so within</p> <pre><code>public class ViewPagerAdapter extends FragmentPagerAdapter </code></pre> <p>an identical construct (as shown above in MainActivity )</p> <pre><code>private List&lt;Fragment&gt; _pages = new ArrayList&lt;Fragment&gt;(); </code></pre> <p>and this syncing (as used above in onSaveInstanceState) is supported specifically by the methods</p> <pre><code>public List&lt;Fragment&gt; exportList() { return _pages; } public void importList(List&lt;Fragment&gt; savedPages) { _pages = savedPages; } </code></pre> <p>And then finally, in the fragment class </p> <pre><code>public class CustomFragment extends Fragment </code></pre> <p>in order for all this to work, there were two changes, first</p> <pre><code>public class CustomFragment extends Fragment implements Serializable </code></pre> <p>and then adding this to onCreate so Fragments aren't destroyed</p> <pre><code>setRetainInstance(true); </code></pre> <p>I'm still in the process of wrapping my head around Fragments and Android life cycle, so caveat here is there may be redundancies/inefficiencies in this method. But it works for me and I hope might be helpful for others with cases similar to mine.</p>
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    1. POViewPager and fragments — what's the right way to store fragment's state?
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    1. USFrank Yin
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    1. COthanks your code is very helpful for me.
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      1. USBrajendra Pandey
 

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