I'm a long time C programmer (not C++), and I decided a few weeks ago to dive into Android app development. My biggest hurdle, was to learn an Object-Oriented Programming language such as Java. I bought and read through two books on the subject:
"Java for Dummies"
"Sam's Learn Java in 24 hours"
The first book gave me a basic understanding of OOP, and the 2nd book gave me some insight on using Java's GUI for creating layouts, buttons, widgets, etc. After reading both books, I felt comfortable enough to program with the Java language.
My next books were Android specific:
"The Busy Coder's Guide to Android Programming"
"Android OS Programming"
I've also been reading every online tutorial I could find on the Internet. Lots to learn, but it's been a exciting process!
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