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copied!<p>You can:</p> <ol> <li>Implement delegate methods in your controller and call them from your view, or</li> <li>Subclass <code>UIControl</code> instead and send <code>UIControlEvent</code>s to your controller</li> </ol> <p>when the values change (or rather when the user interacts with your control).</p> <p>If your view is used to get some form of input from the user, then subclassing <code>UIControl</code> is a better approach.</p> <p>From the iPhone Reference Library:</p> <blockquote> <p><code>UIControl</code> is the base class for controls: objects such as buttons and sliders that are used to convey user intent to the application.</p> </blockquote> <p>So the most important distinction between <code>UIView</code> and <code>UIControl</code> is whether user intent is conveyed or not. <code>UIView</code> is meant to display information, while <code>UIControl</code> is meant to collect user input.</p> <p><strong>UPDATE:</strong></p> <p>If you decide to go with the delegate pattern, here's how your code might look like:</p> <p>In your custom view's interface, define delegate like this:</p> <pre><code>@interface MyView : UIView { id delegate; } @property (assign) id delegate; @end </code></pre> <p>and <code>@synthesize</code> it in the implementation.</p> <p>In your view controller, set the controller to be the delegate:</p> <pre><code>MyView myView = [[MyView alloc] init]; [myView setDelegate:self]; </code></pre> <p>Then, whenever the user interacts with the view (for example in <code>touchesBegan</code>), possibly changing the values, do this in the view:</p> <pre><code>- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { // Possibly change the values if([delegate respondsToSelector:@selector(valuesChanged)]) { [delegate valuesChanged]; } } </code></pre> <p>You might also want to take a look at <a href="http://developer.apple.com/DOCUMENTATION/Cocoa/Conceptual/CocoaFundamentals/CommunicatingWithObjects/CommunicateWithObjects.html#//apple_ref/doc/uid/TP40002974-CH7-SW18" rel="nofollow noreferrer">Delegates and Data Sources</a> in the Cocoa Fundamentals Guide.</p>

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