NSTimer drop-in alternative that doesn't retain the target and supports being used with
The first motivation for this class was to have a type of timer that objects could own and retain, without this creating a retain cycle ( like
NSTimer causes, since it retains its target ). This way you can just release the timer in the
-dealloc method of the object class that owns the timer.
The other problem when using
NSTimer is this note on the documentation:
You must send this message from the thread on which the timer was installed. If you send this message from another thread, the input source associated with the timer may not be removed from its run loop, which could prevent the thread from exiting properly.
More often than not, an object needs to create a timer and invalidate it when a certain event occurs. However, doing this when that object works with a private
GCD queue gets tricky. This timer object is thread safe and doesn't have the notion of run loop, so it can be used with
GCD queues and installed / invalidated from any thread or queue.
The implementation of
MSWeakTimer was reviewed and validated by a
GCD) engineer at the WWDC 2013 Core OS Lab.
How to Use
MSWeakTimer object with this class method:
+ (MSWeakTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)timeInterval target:(id)target selector:(SEL)selector userInfo:(id)userInfo repeats:(BOOL)repeats dispatchQueue:(dispatch_queue_t)dispatchQueue;
Check out the code in the sample app.
- Using CocoaPods:
Just add this line to your
pod 'MSWeakTimer', '~> 1.1.0'
Simply add the files
MSWeakTimer.m to your project.
- Requires ARC. If you want to use it in a project without ARC, mark
MSWeakTimer.mwith the linker flag
- Supports iOS iOS5+ and Mac OSX 10.7+.
MSWeakTimer is available under the MIT license. See the LICENSE file for more info.