为什么retainCount会增加？

Question

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    _testObject = [[TestObject alloc] init];

    NSLog(@"_testObject rc = %d", _testObject.retainCount);
    NSLog(@"testObject rc = %d", self.testObject.retainCount);
}

而testObject是

@property (retain) TestObject *testObject;

为什么这些NSLog()的输出分别是1和2？属性和底层对象的retainCount是否不同？

Answer 1

我猜这是因为你的属性没有被定义为nonatomic，所以你会得到一个保留/自动释放的对象。尝试将您的属性声明更改为：

@property (retain, nonatomic) TestObject *testObject;