obj * A;
obj * B;
obj * C
b.delegate = a;
c.delegate = b;
c发送消息给a的实现方案:c拥有b的delegate,调用b的代理向a发消息。
@interface C
@property (weak, nonatomic) id<BDelegate> delegate;
@end
obj * A;
obj * B;
obj * C
b.delegate = a;
c.delegate = b;
c发送消息给a的实现方案:c拥有b的delegate,调用b的代理向a发消息。
@interface C
@property (weak, nonatomic) id<BDelegate> delegate;
@end