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POConnect to service from abstract superclass in Android
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copied!<p>I am making an application with various activities that all require access to the same database.</p> <p>I've set up an abstract class that has some common elements of all activities (notably the app-specific title bar and some of its behavior, as well as some repeated code and variables).</p> <p>I've set up access to the database through a service. I feel that this service should only ever have one instance.</p> <p>The recommended way to interact and communicate with a server seems to be with binding.</p> <p>That seems a bit cumbersome though (as you need to specify two additional classes - Binder and ServiceConnection), though admmittedly, it all works very well.</p> <p>This is where I run into my issue though: the binding is activity specific. I can query the db from the shared abstract class code, but I can't seem to do the same from subclass code.</p> <p>Code as it appears in my abstract class:</p> <pre><code>protected static DatabaseService autoservice; protected static boolean serviceBound = false; protected static ServiceConnection serviceConnection = new ServiceConnection() { @Override public void onServiceConnected(ComponentName className, IBinder service) { AutoBinder binder = (AutoBinder) service; autoservice = binder.getService(); serviceBound = true; } @Override public void onServiceDisconnected(ComponentName arg0) { serviceBound = false; } }; </code></pre> <p>If I check serviceBound from the subclass, it'll always reply false. I've tried putting it static and non-static.</p> <p>I feel as if the singleton-pattern with getting a static instance of the service might be a (nicer) way to query the DB, but then again, there's probably a reason why Google came up with binding.</p> <p>What would be the best (and cleanest) way to have access to the db from my abstract superclass and its various subclasses?</p>

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