For Android Studio 1.2.2 and above:
What didn't work for me:
Thanks for the question. There are good answers and hints here but for my case where I updated to Android Studio 1.2.2, it didn't work right out of the box. Some answers and blogs suggested that after downloading the xml file,
Save the xml file to ~/Library/Preferences/AndroidStudio/codestyles.
Then restart AndroidStudio
Go to Android Studio -> Preferences -> Code Style -> Java and from Scheme dropdown select the scheme name and save.
However when I put the xml file inside ~/Library/Preferences/AndroidStudio/codestyles/ folder it didn't show my scheme name in the Scheme dropdown to select from.
What worked for me:
After I updated Android Studio to latest version, under ~/Library/Preferences/ in mac, I had two folders: AndroidStudio and AndroidStudio1.2. For importing the AndroidStyle.xml code style file in the updated Android studio, I had to create a folder named codestyles inside ~/Library/Preferences/AndroidStudio1.2/ folder, since none existed. Then I saved the xml file in there and followed the above procedure. Just saving the file solely in .../AndroidStudio/codestyles folder didn't work for me.
Hope it helps someone some day.