nonatomic的作用

@property(nonatomic, retain) UITextField *userName编译时自动生成的代码

- (UITextField *) userName {
    return userName;
}

- (void) setUserName:(UITextField *)userName_ {
    [userName release];
    userName = [userName_ retain];
}

@property(retain) UITextField *userName自动生成的代码

- (UITextField *) userName {
    UITextField *retval = nil;
    @synchronized(self) {
        retval = [[userName retain] autorelease];
    }
    return retval;
}

- (void) setUserName:(UITextField *)userName_ {
    @synchronized(self) {
        [userName release];
        userName = [userName_ retain];
    }
}

http://stackoverflow.com/questions/588866/objective-c-properties-atomic-vs-nonatomic

评论

1 楼 purcharse 2010-09-02  

设置器应该如下写法吧

- (void) setUserName:(UITextField *)userName_ { 
    [userName_ retain]; 
    [userName release]; 
    userName = userName_; 
}