The phone number chooser task is used to launch the built-in Contacts application and allows the user to select a contact. A phone number for the contact is then returned to your app.
To query the user’s contact list without requiring the user to select a contact, use the
Contacts class, described later in this chapter.
PhoneNumberChooserTask should be defined as a field in your class, like so:
readonly PhoneNumberChooserTask phoneNumberChooserTask = new PhoneNumberChooserTask();
Subscribe to the
PhoneNumberChooserTask.Completed event within your class constructor, as shown: