Apple CurrentAddress 示例中的 MKReverseGeocoder 自动释放/释放问题
我正在查看直接从
- (void)dealloc
{
[reverseGeocoder release];
[mapView release];
[getAddressButton release];
[super dealloc];
}
- (IBAction)reverseGeocodeCurrentLocation
{
self.reverseGeocoder =
[[[MKReverseGeocoder alloc] initWithCoordinate:mapView.userLocation.location.coordinate] autorelease];
reverseGeocoder.delegate = self;
[reverseGeocoder start];
}
我想知道分配对象时自动释放的功能是什么。 （reverseGeocoder 是 MapViewController 类中使用保留属性设置的 ivar。）我的应用程序中有与此类似的代码，并且它似乎可以以任何方式工作。
I am looking at this code lifted straight from the MapViewController.m file in the CurrentAddress sample available on Apple's web site:
- (void)dealloc
{
[reverseGeocoder release];
[mapView release];
[getAddressButton release];
[super dealloc];
}
- (IBAction)reverseGeocodeCurrentLocation
{
self.reverseGeocoder =
[[[MKReverseGeocoder alloc] initWithCoordinate:mapView.userLocation.location.coordinate] autorelease];
reverseGeocoder.delegate = self;
[reverseGeocoder start];
}
I am wondering what the function is of the autorelease when allocating the object. (The reverseGeocoder is an ivar in the MapViewController class set up with the retain property.) I have code similar to this in my application, and it seems to work either way.
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（1）
设置
reverseGeocoder属性会增加保留计数 (+1)，但由于您是使用alloc+init创建对象 (+1) ，您需要autorelease(-1)，这样您就不会得到 2 的保留计数。无论哪种方式它都可以工作，唯一的区别是，当您不
自动释放时，就会发生泄漏。确实如此，但请注意，当您使用
self.reverseGeocoder表单时，您不会直接访问 ivar - 相反，您正在调用相关的setReverseGeocoder:函数，可以由您自己编写，也可以由编译器@synthesized。请参阅：http://developer.apple.com /library/mac/#documentation/cocoa/conceptual/MemoryMgmt/MemoryMgmt.html
并且：
为声明的属性合成了哪些等效代码？
Setting your
reverseGeocoderproperty increments the retain count (+1), but since you're creating the object withalloc+init(+1), you need toautorelease(-1) so that you do not end up with a 2 retain count.It does work either way, the only difference is that when you do not
autorelease, you leak.It sure is, but note that when you're using the
self.reverseGeocoderform, you're not accessing the ivar directly - instead, you're calling the relevantsetReverseGeocoder:function, that is either written by yourself or @synthesized by the compiler.See: http://developer.apple.com/library/mac/#documentation/cocoa/conceptual/MemoryMgmt/MemoryMgmt.html
And:
What equivalent code is synthesized for a declared property?