为什么使用 CFPropertyListCreateDeepCopy 时会出现泄漏？

Question

我正在创建字典的深度可变副本，但由于某种原因出现泄漏。我已经尝试过这个：

NSMutableDictionary *mutableCopy = (NSMutableDictionary *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, sectionedDictionaryByFirstLetter, kCFPropertyListMutableContainers);
self.copyOfSectionedDictionaryByFirstLetter = mutableCopy;
CFRelease(mutableCopy);

还有这个：

copyOfSectionedDictionaryByFirstLetter = (NSMutableDictionary *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, sectionedDictionaryByFirstLetter, kCFPropertyListMutableContainers);

两者都被界面生成器的泄漏设备标记。

有什么想法吗？

谢谢！

Answer 1

我的猜测是你正在保留字典中的对象之一。泄漏的字节数是多少？

Answer 2

你真的在你的dealloc方法中释放了copyOfSectionedDictionaryByFirstLetter吗？

您必须执行以下操作：

self.copyOfSectionedDictionaryByFirstLetter = nil;

或：

[copyOfSectionedDictionaryByFirstLetter release];
copyOfSectionedDictionaryByFirstLetter = nil; // Just for good style

Answer 3

我怀疑 NSMutableDictionary 的直接情况使分析器感到困惑。请尝试以下操作：

CFMutableDictionaryRef mutableCopy = CFPropertyListCreateDeepCopy(kCFAllocatorDefault, sectionedDictionaryByFirstLetter, kCFPropertyListMutableContainers);
if (mutableCopy) {
    // NOTE: you MUST check that CFPropertyListCreateDeepCopy() did not return NULL.
    // It can return NULL at any time, and then passing that NULL to CFRelease() will crash your app.
    self.copyOfSectionedDictionaryByFirstLetter = (NSMutableDictionary *)mutableCopy;
    CFRelease(mutableCopy);
}

Answer 4

如果您多次调用下面的部分：

NSMutableDictionary *mutableCopy = (NSMutableDictionary *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, sectionedDictionaryByFirstLetter, kCFPropertyListMutableContainers);
self.copyOfSectionedDictionaryByFirstLetter = mutableCopy;
CFRelease(mutableCopy);

您应该将其更改为：

NSMutableDictionary *mutableCopy = (NSMutableDictionary *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, sectionedDictionaryByFirstLetter, kCFPropertyListMutableContainers);
[self.copyOfSectionedDictionaryByFirstLetter release];
self.copyOfSectionedDictionaryByFirstLetter = mutableCopy;
CFRelease(mutableCopy);

我想这可能是泄漏的原因。