程序接收到的信號：EXC_BAD_ACCESS

Question

我在我的UITableViewController子類下面的方法：

-(void)populateDataStorage{ 

NSString *path = [[NSBundle mainBundle] pathForResource:@"FakeData" ofType:@"plist"]; 

if(path){ 
    NSArray *plistData = [[NSArray alloc] initWithContentsOfFile:path]; 
    NSEnumerator *enumerator = [plistData objectEnumerator]; 

    NSArray *personResults; 

    Photo *photo; 
    Person *person; 

    id currItem = [enumerator nextObject]; 

    while (currItem != nil) { 
     photo = (Photo *)[NSEntityDescription insertNewObjectForEntityForName:@"Photo" inManagedObjectContext: [[FlickrFetcher sharedInstance] managedObjectContext]]; 

     photo.name = [currItem objectForKey:@"name"]; 
     photo.path = [currItem objectForKey:@"path"]; 

     NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name = %@", [currItem objectForKey:@"user"]]; 

     personResults = [[FlickrFetcher sharedInstance] fetchManagedObjectsForEntity:@"Person" withPredicate:predicate]; 

     if ([personResults count] > 0) { 
      person = [personResults objectAtIndex:0]; 
     } 
     else { 
      person = (Person *)[NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:[[FlickrFetcher sharedInstance] managedObjectContext]]; 
      person.name = [currItem objectForKey:@"user"]; 
     } 

     photo.person = person; 
     [person addPhotosObject:photo]; 

     NSLog(@"Photo %@ added for user %@", photo.name, person.name); 

     currItem = [enumerator nextObject]; 
    } 

    [plistData release]; 
} 

}

而且我把它在我的應用程序didFinishLaunchingWithOptions方法在我的AppDelegate，方法也是相同AppDelegate，當它被調用時，我得到它在調試時出現的錯誤，如果我不調試這條線，它將運行該方法並加載沒有問題。如果我根本不調試，它將不會調用該方法。

編輯：根據答案更改了代碼問題仍然保持不變，如果我只是運行沒有任何反應，但在調試時出現錯誤。當我調試整個方法時，不顯示錯誤。

Answer 1

您致電NSLog正嘗試訪問person變量的name財產。但是，當你聲明你的person變量時，你沒有初始化它，所以它指向垃圾。你只在else子句中給它一個有效值，所以有時你的NSLog正在訪問一個未初始化的對象。