问题
I have an app which could benefit from the user being able to choose to set an image as the wallpaper (the background image on the "slide to unlock" screen).
Is there a way for non-jailbreak third-party apps to do this? A search for "wallpaper" in the iPhone documentation returns nothing.
回答1:
There is no way to do this with the current SDK, if you want to do it you should file a bug.
回答2:
If you're writing a jailbreak application you can write to /var/mobile/Library/LockBackground.jpg and then kill the Springboard.
来源：https://stackoverflow.com/questions/248982/setting-iphone-wallpaper-locked-screen-background-programmatically