A proxy object used to weak reference the target in a target/selector callback. To use, initialize an instance of JGWeakTarger with the desired target and selector. Then, use the weakTarget and weakSelector property when creating a target/selector callback. JGWeakTarget will maintain a weak reference to the target and relay the recieved callbacks to the selector.

The following example creates a weak reference to self using JGWeakTarget. After creating an instance of JGWeakTarget, the weakTarget and weakSelector properties are used as the target and the selector for the NSTimer. This creates a normally functioning target/selector callback with the difference in that the NSTimer does not hold a strong reference to self. Thus, the timer will not prevent self from being deallocated. Notice that this also implies that, upon deallocation of the class with the weak reference, the timer must be invalidated.

JGWeakTarget *weakSelf = [JGWeakTarget weakTargetWithTarget:self selector:@selector(timerFired:)];
[NSTimer scheduledTimerWithTimeInterval:10 target:weakSelf.weakTarget selector:weakSelf.weakSelector userInfo:nil repeats:YES];

JGWeakTarget can be used with any classes that take target/selector parameters, such as CADisplayLayer and NSTimer. In addition, selectors with or without sender arguments can be used.