Android: How can I programmatically draw text on key guard screen / lock screen?

Is there a way to draw on or modify the key gua开发者_Python百科rd wallpaper programmatically?

It looks simple enough for the home wallpaper, you can use WallpaperManager. But how about for the lock screen wallpaper? I would like to draw some text there.

There is no API to draw on the lock screen.