Chapter 3 - Taking Actions

1. What's the best way to implement event handlers?
   • There isn't one - you need to consider each case, and choose the most appropriate pattern
2. What are the conditions for any methods that changes the state of a user-interface widget?
   • They must be called from the main thread
3. Code running as part of an event handler should fulfill which of the following conditions?
   • Only interact with the user interface - anything else should be done on a worker thread
4. When requesting data from another Activity, the data is returned through which of these?
   • A callback on your Activity object