Thread-safe UIKit methods

问题

I'm trying to find out exactly what methods (names!) became thread safe in UIKit on iOS 4.0.

I've searched through Apple's docs with little success. For instance a UIImage created with imageNamed: is not safe to use on other threads (it will occasionally jettison its CGImage from the main thread), while imageWithCGImage might be(?). Also, I've seen claims that UIColor is safe to use on threads other than the main thread.

Is there some definite guide as to which methods are safe which ones isn't?

Edit: What's interesting is UIKit classes that is interesting to use on separate threads, such as UIImage, UIColor etc.

回答1:

From Apple's documentation:

Note: For the most part, UIKit classes should be used only from an application’s main thread. This is particularly true for classes derived from UIResponder or that involve manipulating your application’s user interface in any way.

Therefore, you really shouldn't be interacting with anything in UIKit on a background thread.

来源：https://stackoverflow.com/questions/6087068/thread-safe-uikit-methods