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    <p>You should look at creating your own <a href="http://developer.android.com/reference/android/os/ResultReceiver.html" rel="noreferrer"><code>ResultReceiver</code></a> subclass in your activity. <code>ResultReceiver</code> implements <code>Parcelable</code> so can be passed from your <code>Activity</code> to your <code>Service</code> as an extra on the <code>Intent</code>.</p> <p>You'll need to do something like this:</p> <ol> <li><p>Implement a subclass of <code>ResultReceiver</code> within your activity class. The key method to implement is <code>onReceiveResult()</code>. This method provides you a with <code>Bundle</code> of result data which can be used to pass whatever information you are retrieving in your <code>Service</code>. Simply unpack the data you need and use it to update your activity. </p></li> <li><p>In your activity, create a new instance of your custom <code>ResultReceiver</code> and add it to the <code>Intent</code> you use to start your service.</p></li> <li><p>In your <code>Service</code>'s <code>onStartCommand()</code> method, retrieve the <code>ResultReceiver</code> passed in on the <code>Intent</code> and store it in a local member variable.</p></li> <li><p>Once your <code>Service</code> completes its work, have it call <code>send()</code> on the ResultReceiver passing whatever data you want to send back to the activity in a <code>Bundle</code>. </p></li> </ol> <p>This is a pretty effective pattern and means you're not storing data in nasty static variables. </p>
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    1. POHow to get results from an IntentService back into an Activity?
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    1. COThanks for the quick reply! Two follow up questions. First, if I switch to using intent extras as you suggested, is there a good, simple code example of the pattern you outlined? Second, if I wanted to stick with the global variable approach (in this case, fairly innocuous, as the data it holds does not change very much or very often), how would I do it? Is there a way to pull the click listener out of onCreate(), or otherwise synchronize the Activity and Service?
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    2. COThe fundamental problem you have is that the Service runs completely independently of the Activity and takes an indeterminate amount of time to complete. The "correct" solution to this problem is using some kind of asynchronous callback mechanism (which is what the ResultReceiver does for you). The alternative is to repeatedly poll some sort of `isRunning` static variable in your activity to detect when the service is finished and then read the data from another static variable. That's pretty inefficient though and probably requires a dedicated background thread - not recommended.
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    3. COI tried, but just started here and apparently don't have enough reputation points yet. But your answer was excellent, and cracked the nut that kept me up til 3 am last night. Thanks!
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