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    <blockquote> <p>The worker thread uses Thread.sleep() to perform an efficient delay, wakes up to "do things", sends an update to the UI thread's Handler, and repeats.</p> </blockquote> <p>It is possible this is the the right thing for your app, but since you decided not to describe your actual business problem, it is difficult to tell. For example, if you were writing an email client, and you needed to get control every 15 minutes to check for new email, your proposed solution would be unreliable.</p> <blockquote> <p>The next part is apparently difficult in Android</p> </blockquote> <p>Not especially.</p> <blockquote> <p>The worker thread must have a Looper to create a Handler so it can RECEIVE messages</p> </blockquote> <p>Only if you want to use a <code>Handler</code> for that.</p> <p>Java, as a programming language, has been around for a fairly long time. It has many means of inter-thread communication. <code>Handler</code>, <code>Looper</code>, and <code>HandlerThread</code> wrap around these to offer one particular pattern. That pattern is not suitable for all scenarios, as you have noted. However, the rest of Java still exists, and many standard Java classes are part of Android that you can take advantage of.</p> <p>So, for example, you could use a <code>LinkedBlockingQueue</code>. Have the main application thread put commands onto that queue. Your worker thread, rather than using <code>sleep()</code>, would use <code>poll()</code> with a timeout to either pull an event from the queue or wake up after a period of time.</p>
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    1. POAndroid worker thread with its own Handler/Looper
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    1. COExcellent, this is exactly what I was looking for. It reminds me of Completion Ports in Windows, complete with the optional timeout. Android's docs are, not surprisingly, Android-centric so I found no mention of LinkedBlockingQueue. I will begin RTFM immediately... thank you!
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    2. CO@AndroidNewbie: "I found no mention of LinkedBlockingQueue" -- it's in the JavaDocs. It's also in various Java resources, like the book "Java Concurrency in Practice".
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    3. COOne questions remains: With several blocking queue mechanisms native to Java, why doesn't Android just use one of them? Why create the whole new Handler/Looper construct when there are several other, existing, native options?
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