Summary

In this chapter, we have seen how the observer pattern can be used as a tool to manage the delivery of user notifications, as well as keeping track of many other events and responding accordingly. We began by looking at the pattern itself and then at the Android notification APIs, which despite using the system-controlled status bar and notification drawer, allow us a great deal of freedom when it comes to designing notifications that suit the purpose and look of our apps.

In the next chapter, we will take this and other patterns and see how we can extend extant Android components and have them apply our design patterns directly. We will then see how this can help us when it comes to developing for form factors other than phones and tablets.