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    <p>This is a sneaky one. SharedPreferences keeps listeners in a WeakHashMap. This means that you cannot use an anonymous inner class as a listener, as it will become the target of garbage collection as soon as you leave the current scope. It will work at first, but eventually, will get garbage collected, removed from the WeakHashMap and stop working.</p> <p>Keep a reference to the listener in a field of your class and you will be OK, provided your class instance is not destroyed.</p> <p>i.e. instead of:</p> <pre><code>prefs.registerOnSharedPreferenceChangeListener( new SharedPreferences.OnSharedPreferenceChangeListener() { public void onSharedPreferenceChanged(SharedPreferences prefs, String key) { // Implementation } }); </code></pre> <p>do this:</p> <pre><code>// Use instance field for listener // It will not be gc'd as long as this instance is kept referenced listener = new SharedPreferences.OnSharedPreferenceChangeListener() { public void onSharedPreferenceChanged(SharedPreferences prefs, String key) { // Implementation } }; prefs.registerOnSharedPreferenceChangeListener(listener); </code></pre> <p>The reason unregistering in the onDestroy method fixes the problem is because to do that you had to save the listener in a field, therefore preventing the issue. It's the saving the listener in a field that fixes the problem, not the unregistering in onDestroy.</p> <p><strong>UPDATE</strong>: The Android docs have been <a href="http://developer.android.com/reference/android/content/SharedPreferences.html#registerOnSharedPreferenceChangeListener(android.content.SharedPreferences.OnSharedPreferenceChangeListener)" rel="noreferrer">updated</a> with <a href="http://developer.android.com/guide/topics/ui/settings.html#Listening" rel="noreferrer">warnings</a> about this behavior. So, oddball behavior remains. But now it's documented.</p>
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    1. COThis was killing me, I thought I was losing my mind. Thank you for posting this solution!
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      1. USBrad Hein
    2. COThis post is HUGE, thanks a lot, this could have cost me hours of impossible debugging!
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      1. USKevin Gaudin
    3. COAwesome, this is just what I needed. Good explanation too!
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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