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POAndroid Service updates table; How to get corresponding ListView to update?
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copied!<p>Let's say I have a long-running service that monitors a network of external devices. Whenever it discovers a new device in the network, it adds a row to a table in a local SQLite database, and whenever it detects a change of state on a known device, it updates the corresponding row in the table. (BTW, there's no way to predict how frequently or infrequently these discoveries and updates will occur -- the external network marches to its own drummer!)</p> <p>Now, let's also say I have an Activity (in the same process) that includes a ListView backed by the above-mentioned table. At the precise moment that the ListView is initially populated, it's of course in sync with the backing table -- but a moment (or two, or three) afterwards, because of changes in the external device network, the table changes, courtesy of the Service.</p> <p>What's the best way for the Service to inform the Activity that it needs to refresh the ListView, i.e., call requery() on the Cursor, and then call notifyDataSetChanged() on the adapter?</p> <p>I've seen a couple of posts here on SO in which the approach seemed to be "register a broadcastReceiver on the Activity, and send a broadcast Intent from the Service" -- but that seems a bit overkill for a local Service. Isn't there some simpler way? </p> <p>For instance, I'm thinking that since I can get a handle to the local Service object via a Binder object, I might be able to register some kind of callback to the Activity, to be called by the service when needed. Does this sound like it would work? (Or would I be entering blind alley?)</p> <p>Looking forward to your insights.</p> <p>M</p>

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