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    <p>I don't see any problem with that. Pre-ARC, I've always made my IBOutlets <code>assign</code>, as they're already retained by their superviews. If you make them <code>weak</code>, you shouldn't have to nil them out in viewDidUnload, as you point out. </p> <p>One caveat: You can support iOS 4.x in an ARC project, but if you do, you can't use <code>weak</code>, so you'd have to make them <code>assign</code>, in which case you'd still want to nil the reference in <code>viewDidUnload</code> to avoid a dangling pointer. Here's an example of a dangling pointer bug I've experienced:</p> <p>A UIViewController has a UITextField for zip code. It uses CLLocationManager to reverse geocode the user's location and set the zip code. Here's the delegate callback:</p> <pre><code>-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation { Class geocoderClass = NSClassFromString(@"CLGeocoder"); if (geocoderClass &amp;&amp; IsEmpty(self.zip.text)) { id geocoder = [[geocoderClass alloc] init]; [geocoder reverseGeocodeLocation:newLocation completionHandler:^(NSArray *placemarks, NSError *error) { if (self.zip &amp;&amp; IsEmpty(self.zip.text)) { self.zip.text = [[placemarks objectAtIndex:0] postalCode]; } }]; } [self.locationManager stopUpdatingLocation]; } </code></pre> <p>I found that if I dismissed this view at the right time and didn't nil self.zip in <code>viewDidUnload</code>, the delegate callback could throw a bad access exception on self.zip.text.</p>
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    1. POShould IBOutlets be strong or weak under ARC?
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    1. USChristopher Pickslay
    1. USChristopher Pickslay
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    1. COIt is also my understanding that `weak` properties do not need to be nilled in `viewDidUnload`. But why does Apple’s template for creating outlets include a `[self setMySubview:nil]`?
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      1. USYang Meyer
    2. CO@Yang, I'm wondering the same
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    3. COIs there any real world cases where using strong/retained for your IBOutlet could cause problem? Or is it just a redundant retain, which means bad coding style but wouldn't affect your code?
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      1. USEnzo Tran
 

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