Importing user's Facebook credentials into iOS6
问题 The documentation for the new Facebook SDK 3.0 tells us this: "In some cases, the iOS device won't have an access token for a user who has already connected an app to their Facebook account. This can happen when a user used an app's website or used the app on another mobile device. To use the iOS 6 native Auth Dialog, apps need to 'import' the user's credentials into the device and need to show the iOS 6 native Auth Dialog." (see http://developers.facebook.com/docs/howtos/ios-6/, tip 2) I'd