navigationController:willShowViewController:animated:问题

Question

我的应用程序现在只适用于iOS 7和iOS 8，我对这种方法有一个问题：

-(void)navigationController:(UINavigationController *)navigationController 
    willShowViewController:(UIViewController *)viewController 
    animated:(BOOL)animated
{
     ...
}

这只在iOS 7中被调用，文档并没有说iOS 8或其他东西中不推荐这样做。怎么了，知道吗？

我在小牛中使用xcode版本6.0.1 (6A317)

我在另一个类中宣布代表：

ABPeoplePickerNavigationController *contactos = [[ABPeoplePickerNavigationController alloc] init];
contactos.displayedProperties = [NSArray arrayWithObject:[NSNumber numberWithInt:kABPersonPhoneProperty]];

// Delegate
pickerDelegate = [[PickerDelegate alloc] init];
contactos.peoplePickerDelegate  = pickerDelegate;
contactos.topViewController.navigationController.delegate = pickerDelegate;

PickerDelegate.h：

#import <Foundation/Foundation.h>
#import <AddressBook/AddressBook.h>
#import <AddressBookUI/AddressBookUI.h>

@interface PickerDelegate : NSObject <UINavigationControllerDelegate, ABPeoplePickerNavigationControllerDelegate, ABPersonViewControllerDelegate, ABNewPersonViewControllerDelegate>
{
    ...
}

Answer 1

问题是您没有设置ABPeoplePickerNavigationController的delegate (UINavigationControllerDelegate)。您正在设置它的pickerDelegate (ABPeoplePickerNavigationControllerDelegate)，但这不是一回事。