Assign attribute must be unsafeunretained

Assign attribute must be unsafeunretained

During the use of the Protocol today

 

@ Interface AppDelegate () {id

 
  
Testdelegate;} @ property (nonatomic, assign) id

  
   
Testdelegate; @ end @ implementation AppDelegate @ synthesize testdelegate;

  

 

An error is reported:

 

Existing instance variable 'delegate' for property 'delegate'Assign attribute must beUnsafe unretained

Modify:

 

@ Interface AppDelegate () {_ unsafe_unretained id

 
  
Testdelegate;} @ property (nonatomic, assign) id

  
   
Testdelegate; @ end @ implementation AppDelegate @ synthesize testdelegate;

  

 

All right, this is only for compatibility with versions earlier than iOS4