CPLockController is UIViewController subclass that allows users to set a 4 digit passcode or enter one.

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1. Add CPLockController.h/.m to your project.

2. Import CPLockController.h to your class header

    #import "CPLockController.h"
   

3. Make your class follow the CPLockControllerDelegate protocol:

    @interface SampleAppViewController : UIViewController <CPLockControllerDelegate>
   

4. Implement CPLockControllerDelegate methods:

    #pragma mark CPLockControllerDelegate Methods
    
    - (void)lockControllerDidFinish:(NSString*)passcode {
    	//called when the controller is finished
    	//a passcode is passed only when setting a new code
    	if(passcode){
    		NSLog(@"new passcode: %@",passcode);
    	} else {
    		NSLog(@"passcode accepted!");
    	}
    }
    
    - (void)lockControllerDidCancel {
    	//called when user hits cancel button
    	NSLog(@"user cancelled auth");
    }
   

5. For setting a new passcode:

    CPLockController *lockController = [[CPLockController alloc]initWithStyle:CPLockControllerTypeSet];
    lockController.delegate = self;
   

6. For authorizing a user with a passcode:

    CPLockController *lockController = [[CPLockController alloc]initWithStyle:CPLockControllerTypeAuth];
    lockController.passcode = @"1234";  //this is the passcode the user needs to enter
    lockController.delegate = self;
   

6a. If using with an iPad, it is recommended to display using the UIModalPresentationFormSheet style lockController.modalPresentationStyle = UIModalPresentationFormSheet;

6b. If you want to delegate acceptance of the passcode to your own logic (e.g. comparing to a stored hash), implement the optional protocol: - (BOOL)lockController:(CPLockController *)lockController shouldAcceptPasscode:(NSString *)passcode;

7. That's it! Optional customization: //Customize the navigation item title lockController.title = @"Passcode is 1234";

    //Customize the passcode prompt
    lockController.prompt = @"Please enter your passcode";
    
    //Show passcode during entry- default is YES
    lockController.hideCode = NO;
   

8. If you need to localize the default prompts, they are located at the top of CPLockController.m

    #define kCPLCDefaultSetPrompt			@"Enter your new passcode"
    #define kCPLCDefaultAuthPrompt			@"Enter your passcode"
   
    #define kCPLCDefaultSetTitle			@"Set Passcode"
    #define kCPLCDefaultConfirmTitle		@"Confirm Passcode"
    #define kCPLCDefaultAuthTitle			@"Enter Passcode"
   
    #define kCPLCDefaultSetError			@"Passcodes did not match. Try again."
    #define kCPLCDefaultAuthError			@"Passcode incorrect. Try again."