ARC error when declaring delegate ivar

I am using ARC (no, this is not NDA). I am declaring my ivar in my interface with

id itemDelegate;

I then declare the property:

@property (nonatomic, weak) id<mySecretDelegateYouAreNotSupposedToSeeOnSO> itemDelegate; (with weak instead of assign because of ARC)

In my implementation file I simply synthesize it: @synthesize itemDelegate;

However, I am getting the error:

"Existing ivar 'ItemDelegate' for _weak property 'itemDelegate' must be _weak".

Anyone know what's wrong? Thanks for your help.

ARC - Automati开发者_如何转开发c Reference Counting

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Try something like the following (example from: http://vinceyuan.blogspot.com/2011/06/wwdc2011-session-323-introducing.html):

@interface SomeObject : NSObject {
   __weak id <SomeObjectDelegate> delegate;
}
@property (weak) id <SomeObjectDelegate> delegate;
@end

Please notice how the ivar is declared.

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With ARC and iPhone Simulator 5.0 the following seems to work just fine (no warnings, etc...):

SomeObject.h

@class SomeObject;
@protocol SomeObjectDelegate <NSObject>
- (void)someObjectDidFinishDoingSomethingUseful:(SomeObject *)object;
@end


@interface SomeObject : NSObject {
   __unsafe_unretained id <SomeObjectDelegate> _delegate;
}
@property (nonatomic, assign) id <SomeObjectDelegate> delegate;
@end

SomeObject.m

#import "SomeObject.h"

@implementation SomeObject
@synthesize delegate = _delegate;
@end

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