Do I need to declare a private variable for an IBOutlet* property?

Question

Let's say I have a simple view controller with one UITableView property:

@interface MyViewController : UIViewController {
    UITableView *tv;  // <-- DO I NEED THIS??
}
@property (nonatomic, retain) IBOutlet UITableView *tv;
@end

Do I actually need to declare the UITableView *tv ? I've found that even if I don't declare it (and simply @synthesize the property), everything works fine. Yet, lots of code samples explicitly declare the variable. I'm not sure what the benefit of declaring it (or the harm of not declaring it) is.

Answer 1

No you do not have to declare it, synthesize will take care of dynamically injecting the code at compile time. You will on the other hand not be able to inspect the variable directly in Xcode if you do not declare it, that's the downside.

Answer 2

In Objective-C 2.0, the compiler will synthesize the storage for you as well as the accessors. That didn't used to be the case, hence all the examples where people explicitly declare the ivar.