如何使用Monotouch从IntPtr获取ABPerson

Question

Is there a way in Monotouch how to get ABPerson object from an IntPtr. I'm using ABPeoplePickerNavigationController and its ABPeoplePickerNavigationControllerDelegate. I have to read some properties of selected person in method ShouldContinue. My code looks like this:

ABPeoplePickerNavigationController nc = new ABPeoplePickerNavigationController();
nc.Delegate = new CustomABPeoplePickerNavigationControllerDelegate();

And my custom delegate looks like this:

public class CustomABPeoplePickerNavigationControllerDelegate : ABPeoplePickerNavigationControllerDelegate
{           
   public override bool ShouldContinue (ABPeoplePickerNavigationController peoplePicker, IntPtr selectedPerson)
   {
       // *** HERE I HAVE TO GET ABPerson FROM IntPtr ***
       peoplePicker.DismissModalViewControllerAnimated(false);
       return true;
   }
}   

Answer 1

Sadly the ABPerson constructor that accept an IntPtr is internal in MonoTouch. You can either:

• use reflection to call the .ctor
• use another API to retrieve the ABPerson instance

but you cannot use inheritance to solve this since the base (ABRecord) .ctor is also internal.

I'll look why this .ctor is internal (afaik many of such .ctor are public in MonoTouch) and, if possible (ie if there's no alternatives), fix this for upcoming releases.

EDIT: further reading suggest that you use the SelectPerson event on ABPeoplePickerNavigationController. This will use an internal delegate that will convert the IntPtr into a ABPerson instance, solving your issue :)

Answer 2

还没有尝试过，但是您可以：

ABPerson person = peoplePicker.AddressBook.SingleOrDefault(s => s.Handle == selectedPerson) as ABPerson;