CODE

Question

我正在申请,我收到了EXC_BAD_ACCESS错误。

CODE

@interface DNProjectsCategory : DNCategory {
  NSArray *projects;
}

@property(nonatomic, retain) NSArray *projects;

@end

而且:

@implementation DNProjectsCategory
@synthesize projects;

// MEM

- (void)dealloc {
  [projects release];
  
  [super dealloc];
}

// INIT.
- (id)init {
  if (self = [super init]) {
    title = NSLocalizedString(@"PROJECTS", nil);
    isSubCategory = NO;
    
    // Initialize projects
    //!!LINE 32 IS HERE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    projects = [NSArray arrayWithContentsOfFile:DNPROJECTSFILE];
  }
  
  return self;
}

// CATEGORIES

- (NSArray *)subCategories {
  NSMutableArray *projectsArray = [[[NSMutableArray alloc] init] autorelease];
  
  for (NSDictionary *project in projects) {
    DNCategory *projectCategory = [[DNCategory alloc] initWithTitle:[project valueForKey:@"title"]
                                                      subCategories:nil
                                                      isSubCategory:YES];
    
    [projectsArray addObject:projectCategory];
    [projectCategory release];
  }
  
  return projectsArray;
}

CONTENTS OF DNPROJECTSFILE

见。

CONSOLE & INSTRUMENTS

这是科索尔在跑时所说的话(SNSZombie被允许):

run
[Switching to process 41257]
Running…
2010-10-09 23:32:36.899 Done[41257:a0f] *** -[CFString isKindOfClass:]: message sent to deallocated instance 0x1001caab0
sharedlibrary apply-load-rules all

这里是乌克兰航天局试验中所说的:

Zombie Messaged

向地址:0x10012af80发送了目标C电文。

Stack Trace

   0 CoreFoundation _CFRuntimeCreateInstance
   1 CoreFoundation __CFStringCreateImmutableFunnel3
   2 CoreFoundation CFStringCreateWithBytes
   3 CoreFoundation _uniqueStringForCharacters
   4 CoreFoundation getString
   5 CoreFoundation parseXMLElement
   6 CoreFoundation parseXMLElement
   7 CoreFoundation parseArrayTag
   8 CoreFoundation parseXMLElement
   9 CoreFoundation parsePListTag
  10 CoreFoundation parseXMLElement
  11 CoreFoundation _CFPropertyListCreateFromXMLStringError
  12 CoreFoundation _CFPropertyListCreateWithData
  13 CoreFoundation CFPropertyListCreateFromXMLData
  14 Foundation _NSParseObjectFromASCIIPropertyListOrSerialization
  15 Foundation +[NSArray(NSArray) newWithContentsOf:immutable:]
  16 Foundation +[NSArray(NSArray) arrayWithContentsOfFile:]
  17 Done -[DNProjectsCategory init] /Users/rsonic/Developer/Done/DNProjectsCategory.m:32
  18 Done -[DNBindingsController categories] /Users/rsonic/Developer/Done/DNBindingsController.m:18
  19 Foundation -[NSObject(NSKeyValueCoding) valueForKey:]
  20 Foundation -[NSObject(NSKeyValueCoding) valueForKeyPath:]
  21 AppKit -[NSBinder valueForBinding:resolveMarkersToPlaceholders:]
  22 AppKit -[NSArrayDetailBinder _refreshDetailContentInBackground:]
  23 AppKit -[NSObject(NSKeyValueBindingCreation) bind:toObject:withKeyPath:options:]
  24 AppKit -[NSIBObjectData nibInstantiateWithOwner:topLevelObjects:]
  25 AppKit loadNib
  26 AppKit +[NSBundle(NSNibLoading) _loadNibFile:nameTable:withZone:ownerBundle:]
  27 AppKit +[NSBundle(NSNibLoading) loadNibNamed:owner:]
  28 AppKit NSApplicationMain
  29 Done main /Users/rsonic/Developer/Done/main.m:13
  30 Done start

QUESTION

我确实不知道如何确定这一双重释放。就我所知,除<代码>dealloc外,在任何地方均不发放<代码>项目。有些人能否帮助我? 感谢。

Answer 1

You are not using the accessor, so projects is never retained. Two choices f或your init method:

projects = [[NSArray arrayWithContentsOfFile:DNPROJECTSFILE] retain];

或

self.projects = [NSArray arrayWithContentsOfFile:DNPROJECTSFILE];

@property(nonatomic, retain) NSArray *projects;

the property "creates" two methods, a getter - (NSArray *)projects and a, in your case more important, setter - (void)setProjects:(NSArray*)a; The retain statement which you wrote in your property declaration only applies to the setter. If you set the variable directly with projects = foo; the setter is not used.
But self.projects = foo; is equivalent to [self setProject:foo], which is your dynamically created setter.
Your setter looks similar to this:

- (void)setProjects:(NSArray*)anArray {
    [anArray retain];
    [projects release];
    projects = anArray;
}

So if you use the setter, your autoreleased NSArray you got from arrayWithContentsOfFile: is retained.
Every call you make in Objective C that is not "alloc", "copy", "retain" 或anything starting with new returns an autoreleased object. You have to retain those if you want to use them later (i.e. after you left the method where they were created).

或许请大家再看。

CODE

CONTENTS OF DNPROJECTSFILE

CONSOLE & INSTRUMENTS

Zombie Messaged

Stack Trace

QUESTION

友情链接