從ABAddressBookRequestAccessWithCompletion（）中獲取聯繫人數組給出無

Question

我試圖使用NSLog()將所有手機的聯繫人打印到控制檯。目前這個代碼只是打印(null)。

.H

@property (nonatomic, strong) NSMutableArray *contactsObjects; 

.M

@synthesize contactsObjects; 
//lazy instantiation. 
- (NSMutableArray *)contactsObjects 
{ 
    if(!contactsObjects) 
    { 
     contactsObjects = [[NSMutableArray alloc]init]; 
    } 

    return contactsObjects; 
} 

- (void)viewWillAppear:(BOOL)animated 
{ 
    CFErrorRef error = nil; 

    // Request authorization to Address Book 
    ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, &error); 

    if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusNotDetermined) { 
     ABAddressBookRequestAccessWithCompletion(addressBookRef, ^(bool granted, CFErrorRef error) { 
      if (granted) { 
       // First time access has been granted, add all the user's contacts to array. 
       CFMutableArrayRef contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 
      } else { 
       // User denied access. 
       // Display an alert telling user that they must allow access to proceed to the "invites" page. 
      } 
     }); 
    } 
    else if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusAuthorized) { 
     // The user has previously given access, add all the user's contacts to array. 
     CFMutableArrayRef contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 
    } 
    else { 
     // The user has previously denied access 
     // Send an alert telling user that they must allow access to proceed to the "invites" page. 
    } 

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

我來到這裏兩個警告：

我不知道我我應該這樣做才能正確地將我的聯繫人的姓名和號碼打印到控制檯。

如何打印我的聯繫人姓名和電話號碼？

Answer 1

你必須與你的代碼的範圍問題。 viewWillAppear:中的contactsObjects變量與您稱爲contactsObjects的ivar無關。您正在聲明使用相同名稱的新變量。另一方面，最後的NSLog()是伊娃。但是設置其他變量並沒有將任何東西放入伊娃，因此您會看到(null)，這是NSLog()代表「無對象」的方式。

通過不做新變量聲明，但使用伊娃來解決這個問題。

if (granted) { 
    contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 

else if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusAuthorized) { 
    contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 

您還需要轉換這些：（。此外，該函數不返回可變數組，所以你可能有麻煩下來，道路）

contactsObjects = (__bridge_transfer NSArray *)ABAddressBookCopyArrayOfAllPeople(addressBookRef); 

第二個問題是ABAddressBookRequestAccessWithCompletion()不停止並等待其完成Block運行。在請求訪問的同時，其餘的方法繼續進行，因此您在達到NSLog()之前實際設置contactsObjects。

Answer 2

你說它打印出null，你會得到一個錯誤。但這會解釋你的錯誤。

contactObjects在if塊和else if塊中定義。所以當你超出你的條件時，它就不再被定義。

試試這個

- (void)viewWillAppear:(BOOL)animated 
{ 
    CFErrorRef error = nil; 

    // Request authorization to Address Book 
    ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, &error); 

    if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusNotDetermined) { 
     ABAddressBookRequestAccessWithCompletion(addressBookRef, ^(bool granted, CFErrorRef error) { 
      if (granted) { 
       // First time access has been granted, add all the user's contacts to array. 
       contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 
      } else { 
       // User denied access. 
       // Display an alert telling user that they must allow access to proceed to the "invites" page. 
      } 
     }); 
    } 
    else if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusAuthorized) { 
     // The user has previously given access, add all the user's contacts to array. 
     contactsObjects = ABAddressBookCopyArrayOfAllPeople(addressBookRef); 
    } 
    else { 
     // The user has previously denied access 
     // Send an alert telling user that they must allow access to proceed to the "invites" page. 
    } 

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