问题
I create a timer with [NSTimer scheduledTimerWithTimerInterval:target:selector:...] from a background thread
It seems the timer created from a background thread doesn't call the selector given as the argument.
Is there something special I need to run a timer from background thread?
Thank you
- EDIT
Here's the sequence
performSelectorInBackground: pushViewController
from the viewController's init sequence,
I alloc a timer with the above method.
and the timer selector won't get called.
回答1:
You should only do things to the UI - like pushing view controllers and changing UI items - from the main thread. If you don't, things break, as you can see.
See the Cocoa Fundamentals Guide section titled "Are the Cocoa Frameworks Thread Safe?": it says "All UIKit objects should be used on the main thread only."
Original answer
There's nothing special needed. The selector will get called on the thread you did the scheduleTimer call from.
来源：https://stackoverflow.com/questions/5484510/iphone-start-timer-from-background-thread