Your app can present an interface allowing the user to edit and send a mail message or an SMS message. Two view controller classes are provided by the Message UI framework; you’ll need to
import MessageUI. In addition, the Social framework lets you post to Twitter or Facebook on the user’s behalf. You’ll need to
import Social. The classes are:
UIActivityViewController (Chapter 13) also provides a unified interface for permitting the user to choose any of the built-in messaging milieus and to send a message through it. However, the Message UI framework and the Social framework remain important, because the user can be presented with a message form without having to pass through an activity view, and because you can fill in fields, such as the To field in a mail composition form, that UIActivityViewController doesn’t let you fill in.
New in iOS 8, you write your own share extension to appear in the top row of a UIActivityViewController in any app. This book doesn’t discuss how to write a share extension.
The MFMailComposeViewController class, a UINavigationController, allows the user to edit a mail message. The user can ...