VENTouchLock secures your app by requiring a Touch ID fingerprint scan or passcode to gain access when the app is launched cold or from the background. It is used in the official Venmo app.

Installation

The easiest way to get started is to use CocoaPods. Just add the following line to your Podfile:

pod 'VENTouchLock', '~> 1.0'

Usage

1. Create a splash view controller

VENTouchLock requires a custom splash view controller to hide the contents of your app during app-switch and present the Touch ID prompt or passcode view controller. In order to create one, subclass VENTouchLockSplashViewController and override its init function with any customization. The splash view controller is usually a good place to give your users the option to logout in case another user is attempting to sign in.

2. Start the framework

Add the VENTouchLock header file to your app delegate. Import this header in any of your implementation files to use the framework.

#import <VENTouchLock/VENTouchLock.h>

Add the following code to initialize VENTouchLock in your app delegate's application:didFinishLaunchingWithOptions: method.

[[VENTouchLock sharedInstance] setKeychainService:@"KEYCHAIN_SERVICE_NAME"
                                  keychainAccount:@"KEYCHAIN_ACCOUNT_NAME"
                                    touchIDReason:@"TOUCHID_REASON"
                             passcodeAttemptLimit:ATTEMPT_LIMIT
                        splashViewControllerClass:[CUSTOM_SPLASH_VIEW_CONTROLLER class]];

• KEYCHAIN_SERVICE_NAME: A service name used to set and return a passcode from Apple's Keychain Services interface. Example: Venmo
• KEYCHAIN_ACCOUNT_NAME: An account name used to set and return a passcode from Apple's Keychain Services interface. Example: [email protected]
• TOUCHID_REASON: A message displayed on the Touch ID prompt. Example: Scan your fingerprint to unlock
• ATTEMPT_LIMIT: The maximum number of passcode attempts before the splash view controller fails to authenticate (Your app should logout when the user reaches this limit)
• CUSTOM_SPLASH_VIEW_CONTROLLER: The name of the VENTouchLockSplashViewController subclass.

3. Set a passcode

In order for your users to enable Touch ID and / or a passcode, they must set a passcode. In the Venmo app, this option is in the settings page. To let your users create a passcode, use a VENTouchLockCreatePasscodeViewController.

4. Enable Touch ID

If the user's device supports Touch ID (i.e. [VENTouchLock canUseTouchID] returns YES), after setting a passcode prompt, allow the user to set an option to unlock with Touch ID. Set their preference with the VENTouchLock class method setShouldUseTouchID:(BOOL)preference

Sample Project

Check out the sample project in this repo for sample usage.

Contributing

We'd love to see your ideas for improving this library! The best way to contribute is by submitting a pull request. We'll do our best to respond to your patch as soon as possible. You can also submit a new Github issue if you find bugs or have questions.

Please make sure to follow our general coding style and add test coverage for new features!