To help other developers learn Android, Bill Lahti has written blog articles about Android. See http://blahti.wordpress.com for complete notes and explanations for all of the attached sample applications.
Most of these tutorial were done prior to 2017. The zip files are for use with Eclipse.
- Android Example of a Zoomable Game Board - an example application with a game board that can be panned and zoomed.
- How to Implement In-App Billing in Android - a modified version of a sample app from Google for in-app purchases.
- Rotate and Scale Bitmap Example - a simple demo app that shows how to display bitmaps on a canvas with rotation and scaling.
- Store Item Fragment - a fragment that displays an item for sale in a virtual store.
- Tridroid - Switch Fragment Demo - a fragment that implements a simple switch
- Two Progress Bars for Android - an example that shows how to build two simple progress bars for your Android app.
- Drag-Drop for Android GridView (V4) - a demo app that shows how to support drag-drop operations in a GridView.
- Fragments Example V4 - a simple example that shows how to support Fragments in an application for all API levels from Android 2.3.3 (API 10) to Android 4.2 and up (API 17+)
- Multitouch Panning and Zooming Examples for Android
- Three Variations for Image Squares in Android
- Android Images With Clickable Areas