Revisiting the Getting Started Training

In going through the Android Getting Started training, I observed a number of new key elements since Android 1.6 / API 4:

• Action Bar: Introduced in Android 3.0 / API 11, the action bar is a navigation bar at the top of the screen that replaced the navigation functionality provided by the dedicated menu button (no longer required for Android devices).
• Fragments: Also introduced in Android 3.0 / API 11, fragments were introduced to provide a flexible way to combine elements to support varying screen sizes, e.g., phones vs tablets.

Because we want to develop applications that run on virtually all Android devices in use (forces us to support versions Android 2.1 / API 7 or greater), we will be using the v7 Support Libraries that will provide these (and other) newer Android features.

Challenging Documentation (e.g., Action Bar)

One of the challenges in reading this (and other) Android documentation is that there are multiple ways of achieving the end, e.g., with and without the support libraries. While the multiple techniques are fundamentally the same, the devil is in the details and it is easy to get tripped up.

The action bar is an example of a particularly challenging implementation as it requires dealing with both the variation of the use or not of the support libraries and also the introduction of the Toolbar (generalization of the Action Bar) in Android 5.0  / API 21.