[HOW-TO] change Jelly Bean system fonts
after ICS, Google started to use Roboto as android's default english font. so I found 6 types of style here ：
before you replace these, you need to know the font's classification, someone complained that when repaced the Roboto-Bold.ttf, the device restart into boot-loop, I think maybe that was because u replaced a BOLD style with a REGULAR one (android2.3 dones't check this).
FontCreator-6.5-pro(which i use) can change the font's properties.
for example, change a Regular font into Bold, here is the steps:
1、open a regular font(most of fonts in http://www.fonts2u.com/
are regular style) with the FontCreator;
2、Format(in the menubar) -> settings -> Classification;
3、change the "Weight" value into "Bold";
4、change the "Width" value into "Medium(normal)";
5、only tick off a single bold in "Font Design(windows)";
6、only tick off a single bold in "Mac Style".
7、save it and u can use it to replace the Roboto-Bold.ttf file.
How to change the LockScreen Digital Clock Font?
/system/fonts/AndroidOpia.ttf seems no longer be used in Jelly Bean(which android 2.3 use it as LockScreen Clock Font)
so you need to replace those three files to change the lock clock font:
those three files are totally same, and only contains 16 chars: not_def, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, M, P, :, space, 0.
u can edit the original to replace the chars in sequence.(use FontCreator6.5pro)
the attachment fonts was tested in my Nexus 7.