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POBackwards-compatible BackupAgent
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copied!<p>I am looking into using the new Backup API that available since Android 2.2, but need to maintain backwards compatibility (to 1.5 to be exact).</p> <p>The docs state:</p> <blockquote> <p>The backup service and the APIs you must use are available only on devices running API Level 8 (Android 2.2) or greater, so you should also set your android:minSdkVersion attribute to "8". However, if you implement proper backward compatibility in your application, you can support this feature for devices running API Level 8 or greater, while remaining compatible with older devices.</p> </blockquote> <p>I indeed build against the level 8 <code>targetSdkVersion</code> with level 3 <code>minSdkVersion</code> and try to use a wrapper class (with reflection) to overcome the problem that the application will not run if you implement a class that extends an nonexisting class.</p> <p>Here is the problem: since we don't make actual calls to the <code>BackupHelper</code> class ourselves, we can't check upfront if the class indeed exists. (As is explained in the Android Backwards Compatibility documentation with a <code>checkAvailable()</code> method.) The class will therefore be instantiated and cast to a <code>BackupAgent</code>. But since we use reflection, it doesn't actually override BackupAgent and an exception occurs at runtime when the backup is requested:</p> <pre><code>java.lang.RuntimeException: Unable to create BackupAgent org.transdroid.service.BackupAgent: java.lang.ClassCastException: org.transdroid.service.BackupAgent </code></pre> <p>Here is my approach to a backwards compatible <code>BackupAgent</code>: <a href="http://code.google.com/p/transdroid/source/browse/#svn/trunk/src/org/transdroid/service" rel="nofollow noreferrer">http://code.google.com/p/transdroid/source/browse/#svn/trunk/src/org/transdroid/service</a> where the BackupAgent.java is the 'regular' BackupAgentHelper-extending class and BackupAgentHelperWrapper is the reflection-based wrapper class.</p> <p>Anyone successfull in implementing a <code>BackupAgent</code> with backwards compatibility?</p>

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