I was attempting to place my calculations from eecon into an AsyncTask. I initially thought I would make a common task, calling it from both my find factor activity, and my find interest activity. I had to deal with the whole mess of figuring out which one was being called, and whatnot. Then I ran across the problem of getting the data back from the task. I initially tried using the getstatus function that async provides, as well as the get function, this returns the result. Seems great right? WRONG! get is blocking, this means that when I kick off the async task, it doesn't just kick off and run and when it's done let the UI know it's done, I FROZE the UI. This is bad. Now if my calculation is time consuming then we have a chance at a force close. I wanted to try to pass the data back to the UI components so hopefully I wouldn't have to cause the main thread to wait. I wasn't sure how to do this, but after reading about the AsyncTask more, I realized that the onPostExecute was supposed to update the calling UI thread. Finally I realized (after a little reading) you can place the AsyncTask class in as a subclass, this allows it to have access to the parent's elements.
No more blocking and no more force closes from this calculation.