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copied!<p>Though retain cycles are a valid concern, the reasoning for a weak reference is more related to apple's perspective on how to use the delegation pattern with uikit and other elements out of the box which is explained here:</p> <p><a href="http://developer.apple.com/library/IOs/documentation/General/Conceptual/DevPedia-CocoaCore/Delegation.html" rel="noreferrer">http://developer.apple.com/library/IOs/documentation/General/Conceptual/DevPedia-CocoaCore/Delegation.html</a></p> <p>Specifically: "The main value of delegation is that it allows you to easily customize the behavior of several objects in one central object."</p> <p>If the delegate deals with managing the delegated tasks of several objects then those objects need not retain the delegate and should not bear the responsibility of dealllocating the delegate as it might be used by other objects. The weak reference enforces the concept that the management of the delegate is not the delegators responsibility. </p> <p>An example in objective c is a one delegate being used for multiple table views, like when using a table view and a searchdisplaycontroller with a uisearchbar. Apples examples use the controller as the delegate, but reasoning still holds when using one custom delegate for both the main table view and the results table view for your search. That custom delegate would likely be retained by your controller in order to be provided to both table views. </p> <p>This is fundamentally different from the basic delegation pattern that is referred to in other languages where the delegate is often created by the delegator and each instance may manage a its own delegate instance. </p>

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