Objective C subStringToIndex 内存泄漏

Question

我使用 xcode 4.2 for 10.6 和 ios 5，当我使用 xcode 分析项目时，报告了这个奇怪的内存泄漏。

代码如下：

- (void) imagePickerController: (UIImagePickerController*) reader
didFinishPickingMediaWithInfo: (NSDictionary*) info
{
id<NSFastEnumeration> results = [info objectForKey: ZBarReaderControllerResults];
ZBarSymbol *symbol = nil;
for (symbol in results) break;
[reader dismissModalViewControllerAnimated: NO];

[self beep];
NSString *upcScanned = [NSString stringWithFormat:@"0%@", symbol.data]; //line 1
NSString * name = [self getItemName:upcScanned];
ProductNameDialog *dialog = [[ProductNameDialog alloc] initWithNibName:@"ProductNameDialog" bundle:nil];

//dialog.upcScanned = [upcScanned substringToIndex:[upcScanned length] - 1];//line 2
[name release];
[self presentModalViewController:dialog animated:YES];
[dialog release];        
}

line2 是报告内存泄漏的行。

Answer 1

最合乎逻辑、最可能的结论是方法 [self getItemName:upcScanned] 保留传入的字符串但不释放它。