Understanding when and why to use different Android threads
<p>Hopefully someone can explain this to me or point me to a resource I can read to learn more. I am building an app that uses a ListView and a custom list adapter that I modeled off one of the many tutorials available online such as this one:</p>

<p><a href="http://www.softwarepassion.com/android-series-custom-listview-items-and-adapters/">http://www.softwarepassion.com/android-series-custom-listview-items-and-adapters/</a></p>

<p>It worked fine. However, every example of how to do this runs the process of building the list of objects to be displayed and collecting the required data on separate threads. </p>

<p>I want to know why/ Couldn't you just put everything into onCreate? I can't see a reason why you would need separate threads to make this happen. Is there some general form/standard for when/what must me run on certain threads? </p>
