在ABPeoplePickerNavigationController中设置提示

Question

我无法获取此代码来设置提示：

// Create a PeoplePicker
ABPeoplePickerNavigationController *objPeoplePicker = [[ABPeoplePickerNavigationController alloc] init];
[objPeoplePicker setPeoplePickerDelegate:self];

// Customize colors
objPeoplePicker.topViewController.navigationController.navigationBar.tintColor = [UIColor colorWithRed:0.294 green:0.278 blue:0.247 alpha:1.0];
objPeoplePicker.topViewController.searchDisplayController.searchBar.tintColor = [UIColor colorWithRed:0.294 green:0.278 blue:0.247 alpha:1.0];

// Only display phone numbers
NSArray *displayedItems = [NSArray arrayWithObjects:[NSNumber numberWithInt:kABPersonPhoneProperty], nil];
objPeoplePicker.displayedProperties = displayedItems;

// Add a prompt
objPeoplePicker.navigationBar.topItem.prompt = @"Choose a contact to...";

// Show the picker
[self presentModalViewController:objPeoplePicker animated:YES];

“添加提示”部分似乎没有设置提示。有任何想法吗？这是输出的屏幕截图：

Answer 1

这个问题的关键信息，并不是很明显，你需要设置之后的行：

[self presentModalViewController:objPeoplePicker animated:YES];

所以，如果你这样做，它就有效：

[self presentModalViewController:objPeoplePicker animated:YES];
objPeoplePicker.navigationBar.topItem.prompt = @"Choose a contact to...";