iOS Programming Cookbook

How to do it...

1. Create a new Xcode project with the Single View Application template and with name the TouchIDDemo.
2. The demo app will be very simple; we will have a screen with only one button that will notify the authenticating user.
3. Open Main.storyboard and change the layout of the screen to be as follows:

4. Link an IBAction to the button in ViewController.swift to perform the logic of Touch ID authentication:

      @IBAction func didClickOnAuthenticate(_ sender: Any) { 
      } 

5. Add the following import statement at the top of the source file:

      import LocalAuthentication 

6. In the action function, first add the following code to check whether Touch ...