8.3.8. Performing Database Operations Outside the GUI Thread with AsyncTasks

You should perform long-running operations or operations that block execution until they complete (e.g., file and database access) outside the GUI thread. This helps maintain application responsiveness and avoid Activity Not Responding (ANR) dialogs that appear when Android thinks the GUI is not responsive. When we need a database operation’s results in the GUI thread, we’ll use a subclass of AsyncTask (package android.os) to perform the operation in one thread and receive the results in the GUI thread. The details of creating and manipulating threads are handled for you by class AsyncTask, as are communicating the results from the AsyncTask to the GUI thread.