How I can replace default calendar of Android OS?

Question

Is there any official or non-official API or a hack to replace default calendar (Georgian calendar) of Android OS with another calendar (my own Calendar)? You can see list of calendars around the world here if you are not familiar with them.

May I must override DateFormat or GregorianCalendar or Calendar.getInstance()?

(Added on an edit) And will it override use of Gregorian calendar totally, for example on Android lock-screen?

Thanks :)

Answer 1

Calendar.getInstance() is not the Android API. It is standard Java API. Calendar.getInstance() calls createCalendar() with default time zone and locale. There are factory methods getInstance() that accept time zone, locale and both. This is the way to affect the calendar created.

For example as far as I know sending Japanese locale cause creation instance of JapaneseImperialCalendar.

EDIT

There are a couple of predefined calendars: BuddistCalendar and Japanese calendar. And obviously default GregorianCalendar. You can add you own "extension" using Locale.setExtension(char key, String value). I have never done it but it should work. You should however dig into the code your self to find out the correct parameters. Good luck.