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Incorrect decrement of the reference count of an object that is not owned at this point by the caller1
第一种情况
这种问题一般就是变量申请了内存并初始化了,但没有使用此变量,接着将此变量又重新赋值。如下:
NSString *imageString = [[NSString alloc] init];
imageString = @"HResout";
第二种情况
测出的问题提示是 Incorrect decrement of the reference count of an object that is not owned at this point by the caller
问题出现在这一行[self.tableView initWithFrame:self.view.bounds style:UITableViewStyleGrouped];
本人的这个类是继承UITableViewController的,所以它应该会有个成员是tableView的,我想初始化它风格的样式,但是这里出现了这个问题,原因应该是没有创建就初始化了,后来改成这个:
self.tableView =[[[UITableView alloc ]initWithFrame:self.view.boundsstyle:UITableViewStyleGrouped] autorelease];
第三种情况
LoginViewController *loginViewController = [[LoginViewController alloc] initwithLoginUrl: loginUrl];
CustomNavigationController *customNavigationController = [[CustomNavigationController alloc]initWithRootViewController: loginViewController];
customNavigationController.navigationBar.tintColor = NavgaitonBar_Color;
[self.navigationController presentModalViewController: customNavigationController animated: YES];
[loginViewController release];
[customNavigationController release];
红色为提示内存泄露的地方
只要把 LoginViewController *loginViewController = [[LoginViewController alloc] initwithLoginUrl: loginUrl];
修改为 LoginViewController *loginViewController = [[LoginViewController alloc] initWithLoginUrl: loginUrl];
就可以解决内存泄露(就一大小写的差别)
在dealloc方法中使用[self.xxx release]和[xxx release]的区别?
用Xcode的Analyze分析我的Project,会列出一堆如下的提示:
Incorrect decrement of the reference count of an object that is not owned at this point by the caller
仔细看了下代码,都是在dealloc方法中使用了[self.xxx release]这样的语句引起的,把代码改成了[xxx release]就没有问题了
但我不明白究竟原因为何?我的理解是:不管@property xxx这里设定了是retain, copy还是assign,影响的总是setter方法,getter方法不会边,就是简单地return xxx完事了。而self.xxx就是调用[self getXxx]一样的,那么为什么这样的代码会引起Xcode Analyze的警告呢?
比如这里http://blog.csdn.net/diyagoanyhacker/article/details/6996208
他是因为初始化方法拼写错误导致的。
self.xxx调用的是getter,而getter并非想当然的是 - (id) xxx{ return _xxx; }.
有可能是 - (id) xxx{ return [[xxx retain] autorelease]; }还有各种情况。这时候你发release就不只是你想的_xxx接收的了。
所以,在dealloc里面可以这样释放:
self.xxx = nil;
或者是 [_xxx release];
这边有两个帖子,我觉得不错:
链接1:stackoverflow.com/questions/7262268/why-shouldnt-i-use-the-getter-to-release-a-property-in-objective-c
链接2:developer.apple.com/library/ios/documentation/Cocoa/Conceptual/MemoryMgmt/Articles/mmPractical.html#//apple_ref/doc/uid/TP40004447-SW13
--- 查看Don’t Use Accessor Methods in Initializer Methods and dealloc
Incorrect decrement of the reference count of an object that is not owned at this point by the caller1