ABRecordCopyValue可以返回什么？(解决不良访问)

Question

我正在使用这个简单的代码来获取ios 7中地址簿的所有联系人.我的地址中有155个联系人.当我记录人们的姓名时,我从我的地址簿中获取了34个正确的名字(显然是随机的),15个名称为null,然后在第50个项目上,一个糟糕的访问崩溃就行了

   NSString *firstNames = (__bridge NSString*)ABRecordCopyValue(person, kABPersonFirstNameProperty)

我试过登录姓氏,或图像没有变化.我试图避免对null对象进行ABRecordCopyValue而不进行任何更改.我尝试在项目> 50上执行ABRecordCopyValue,并在50到150的项目上得到相同的结果.我做错了什么？什么ABRecordCopyValue可以返回正确的值旁边和null？

+(NSArray *)getAllContactsAddress
{
CFErrorRef *error = nil;
ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, error);

// SUPPOSE access has been granted
BOOL accessGranted = true;

if (accessGranted) {
    ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, error);
    ABRecordRef source = ABAddressBookCopyDefaultSource(addressBook);
    CFArrayRef allPeople = ABAddressBookCopyArrayOfAllPeopleInSourceWithSortOrdering(addressBook, source, kABPersonSortByFirstName);
    CFIndex nPeople = ABAddressBookGetPersonCount(addressBook);
    NSMutableArray* items = [NSMutableArray arrayWithCapacity:nPeople];


    for (int i = 0; i < nPeople; i++)
    {
        ContactsData *contacts = [ContactsData new];

        ABRecordRef person = CFArrayGetValueAtIndex(allPeople, i);

        NSString *firstNames = (__bridge NSString*)ABRecordCopyValue(person, kABPersonFirstNameProperty);

        NSLog(@"%@",firstNames);
    }
}

Answer 1

我认为 ^{(我实际上很确定)}问题是nPeople错误的值并且与allPeople数组中的条目数不匹配,就像你想象的那样.nPeople当你CFArray已经提供了一种直接的方法时,你已经使用了一种奇怪的获取方法.

我认为这会起作用:

CFIndex nPeople = CFArrayGetCount(allPeople);

您还需要在使用之前检查是否person为非NULL:

ABRecordRef person = CFArrayGetValueAtIndex(allPeople, i);
NSAssert(person, @"Non-person detected!");