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copied!<p>You will want to declare a delegate protocol for your class. An example of a delegate protocol and interface for class <code>Foo</code> might look like this:</p> <pre><code>@class Foo; @protocol FooDelegate <NSObject> @optional - (BOOL)foo:(Foo *)foo willDoSomethingAnimated:(BOOL)flag; - (void)foo:(Foo *)foo didDoSomethingAnimated:(BOOL)flag; @end @interface Foo : NSObject { NSString *bar; id <FooDelegate> delegate; } @property (nonatomic, retain) NSString *bar; @property (nonatomic, assign) id <FooDelegate> delegate; - (void)someAction; @end </code></pre> <p>Don't forget to synthesize your properties in the <code>@implementation</code>.</p> <p>What this code did was declare a protocol called FooDelegate; a class that conforms to this protocol would be declared like <code>@interface SomeClass : SuperClass <FooDelegate> {}</code>. Because this class conforms to the protocol <code>FooDelegate</code>, it now gets to implement the methods under <code>FooDelegate</code> (to require that these be implemented, use <code>@required</code> instead of <code>@optional</code>). The last step is for a <code>Foo</code> object to be instantiated in the class that conforms to <code>FooDelegate</code>, and for this <code>Foo</code> object to have its delegate property set:</p> <pre><code>Foo *obj = [[Foo alloc] init]; [obj setDelegate:self]; </code></pre> <p>Now, your class is prepared to receive messages from <code>Foo</code> objects that have their delegates set correctly.</p>

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