Question

I have a viewController (lets call it vcA) and this viewController has a NSArray property declared and synthesized.

NSArray *myProperty;

...
@property (nonatomic, retain) NSArray *myProperty;

and then synthesized on .m

this vcA is a delegate for another viewController, vcB.

Inside vcB I do:

NSArray *getMyPropertyFromDelegate = (NSArray *)[delegate myProperty];

and I receive an error saying warning: Semantic Issue: Instance method ‘-myProperty’ not found (return type defaults to ‘id’)

I know I can silent this warning changing the line to

NSArray *getMyPropertyFromDelegate = (NSArray *)[(vca*)delegate myProperty];

and importing vcA.h, but I am trying to make vcB as independent as possible, because the delegate can change.

How do I do that working just with the delegate property?

thanks

Answer 1

I suggest you write a custom protocol.

Make vca view controller conforming to the protocol, and in vcB, declare the delegate property :

@property(retain) id <MyProtocol> delegate;

This means the delegate can be any type, as long as it conforms to MyProtocol.

Here is an example.

// MyProtocol.h
@protocol MyProtocol <NSObject>

@property(retain) NSArray *myProperty;

@end

// vca.h
@interface vca : XXXX <MyProtocol> {
....
}
@property(retain) NSArray *myProperty;


// vca.m
@synthesize myProperty; // or provide a getter