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copied!<p>I found this to be a HIGHLY confusing issue (one of many that litter the Android landscape). </p> <p><code>setArguments()</code> is a workaround for Android's very unhelpful need to have a parameter-less constructor available for Fragments. </p> <p>My confusion came in waves. First, the methods you naturally override in your <code>Fragment</code> (e.g. <code>onCreate</code>, <code>onCreateView</code>) receive a <code>Bundle</code> parameter that represents the <code>savedInstanceState</code> of your <code>Fragment</code>. This instance state apparently has <strong>NOTHING</strong> whatsoever to do with the values you store via <code>setArguments()</code> and retrieve via <code>getArguments()</code>. Both use a <code>Bundle</code>, both <code>Bundles</code> are likely to be accessed within the same overridden method, neither have anything to do with each other. </p> <p>Second, it's unclear how Android uses <code>setArguments()</code>. Android calls your parameter-less constructor to rebuild your <code>Fragment</code> on rotate, but apparently ALSO will call whichever <code>setArguments()</code> method was last called when the <code>Fragment</code> was constructed. </p> <p>Huh???? </p> <p>Amazing, but true. All of this creating <code>Bundles</code> with <code>setArguments()</code> madness exists to compensate for the need of a parameter-less <code>Fragment</code> constructor. </p> <p>In short, I'm using the static <code>newInstance</code> method to create my <code>Fragment</code>.</p> <pre><code>public MyFragment() { //satisfy Android } public static MyFragment newInstance(long record_id) { Log.d("MyFragment", "Putting " + record_id + " into newInstance"); MyFragment f = new MyFragment(); Bundle args = new Bundle(); args.putLong("record_id", record_id); f.setArguments(args); return f; } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); /** * Perform an immediate check of arguments, * which ARE NOT the same as the bundle used * for saved instance state. */ Bundle args = getArguments(); if(args != null) { record_id = args.getLong("record_id"); Log.d("MyFragment", "found record_id of " + String.valueOf(record_id)); } if(savedInstanceState != null) { //now do something with savedInstanceState } } </code></pre>

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