Preparing for App Academy Coding Exercise
Check out my code on Repl.it: https://t.co/inbxc1pywI
— Ofili Valentine (@valofils) June 10, 2017
Understanding the Delegate pattern
Delegation is a simple and powerful pattern in which one object in a program acts on behalf of, or in coordination with, another object. The delegating object keeps a reference to the other object—the delegate—and at the appropriate time sends a message to it. The message informs the delegate of an event that the delegating object is about to handle or has just handled. The delegate may respond to the message by updating the appearance or state of itself or other objects in the application, and in some cases it can return a value that affects how an impending event is handled. The main value of delegation is that it allows you to easily customize the behavior of several objects in one central object. The delegating object is typically a framework object, and the delegate is typically a custom controller object. In a managed memory environment, the delegating object maintains a weak reference to its delegate; in a garbage-collected environment, the receiver maintains a strong ref...
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