iOS 官方 Demo

基础知识

支持系统和机型

iPhone 5s,最低支持系统为iOS 8,虽然安装iOS 7系统的5s机型可以使用系统提供的指纹解锁功能,但由于API并未开放,所以理论上第三方软件不可使用。

依赖框架

LocalAuthentication.framework

#import <LocalAuthentication/LocalAuthentication.h>


注意事项

iOS 8以下版本适配时,务必进行API验证,避免调用相关API引起崩溃。

使用类

LAContext

代码

- (void)authenticateUser
{
    //初始化上下文对象
    LAContext* context = [[LAContext alloc] init];
    //错误对象
    NSError* error = nil;
    NSString* result = @"Authentication is needed to access your notes.";
    
    //首先使用canEvaluatePolicy 判断设备支持状态
    if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {
        //支持指纹验证
        [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:result reply:^(BOOL success, NSError *error) {
            if (success) {
                //验证成功,主线程处理UI
            }
            else
            {
                NSLog(@"%@",error.localizedDescription);
                switch (error.code) {
                    case LAErrorSystemCancel:
                    {
                        NSLog(@"Authentication was cancelled by the system");
                        //切换到其他APP,系统取消验证Touch ID
                        break;
                    }
                    case LAErrorUserCancel:
                    {
                        NSLog(@"Authentication was cancelled by the user");
                        //用户取消验证Touch ID
                        break;
                    }
                    case LAErrorUserFallback:
                    {
                        NSLog(@"User selected to enter custom password");
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                            //用户选择输入密码,切换主线程处理
                        }];
                        break;
                    }
                    default:
                    {
                        [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                           //其他情况,切换主线程处理 
                        }];
                        break;
                    }
                }
            }
        }];
    }
    else
    {
        //不支持指纹识别,LOG出错误详情
        
        switch (error.code) {
            case LAErrorTouchIDNotEnrolled:
            {
                NSLog(@"TouchID is not enrolled");
                break;
            }
            case LAErrorPasscodeNotSet:
            {
                NSLog(@"A passcode has not been set");
                break;
            }
            default:
            {
                NSLog(@"TouchID not available");
                break;
            }
        }
        
        NSLog(@"%@",error.localizedDescription);
    }
}

  
  
 
 
   
   
 
 
   
    

   
   typedef NS_ENUM(NSInteger, LAError)
{
    //授权失败
    LAErrorAuthenticationFailed = kLAErrorAuthenticationFailed,
    
    //用户取消Touch ID授权
    LAErrorUserCancel           = kLAErrorUserCancel,
    
    //用户选择输入密码
    LAErrorUserFallback         = kLAErrorUserFallback,
    
    //系统取消授权(例如其他APP切入)
    LAErrorSystemCancel         = kLAErrorSystemCancel,
    
    //系统未设置密码
    LAErrorPasscodeNotSet       = kLAErrorPasscodeNotSet,

    //设备Touch ID不可用,例如未打开
    LAErrorTouchIDNotAvailable  = kLAErrorTouchIDNotAvailable,
    
    //设备Touch ID不可用,用户未录入
    LAErrorTouchIDNotEnrolled   = kLAErrorTouchIDNotEnrolled,
} NS_ENUM_AVAILABLE(10_10, 8_0);

操作流程

iOS 8及以上版本执行-(void)authenticateUser方法,方法自动判断设备是否支持和开启Touch ID

iOS 9

感谢秋儿指出iOS 9加入了三种新的错误类型。

/// Authentication was not successful, because there were too many failed Touch ID attempts and
    /// Touch ID is now locked. Passcode is required to unlock Touch ID, e.g. evaluating
    /// LAPolicyDeviceOwnerAuthenticationWithBiometrics will ask for passcode as a prerequisite.
    LAErrorTouchIDLockout   NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorTouchIDLockout,

    /// Authentication was canceled by application (e.g. invalidate was called while
    /// authentication was in progress).
    LAErrorAppCancel        NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorAppCancel,

    /// LAContext passed to this call has been previously invalidated.
    LAErrorInvalidContext   NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorInvalidContext
   
   
  
  
 /// Authentication was not successful, because there were too many failed Touch ID attempts and
    /// Touch ID is now locked. Passcode is required to unlock Touch ID, e.g. evaluating
    /// LAPolicyDeviceOwnerAuthenticationWithBiometrics will ask for passcode as a prerequisite.
    LAErrorTouchIDLockout   NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorTouchIDLockout,

    /// Authentication was canceled by application (e.g. invalidate was called while
    /// authentication was in progress).
    LAErrorAppCancel        NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorAppCancel,

    /// LAContext passed to this call has been previously invalidated.
    LAErrorInvalidContext   NS_ENUM_AVAILABLE(10_11, 9_0) = kLAErrorInvalidContext

LAErrorTouchIDLockout是在8.0中也会出现的情况,但并未归为单独的错误类型,这个错误出现,源自用户多次连续使用Touch ID失败,Touch ID被锁,需要用户输入密码解锁,这个错误的交互LocalAuthentication.framework已经封装好了,不需要开发者关心。LAErrorAppCancelLAErrorSystemCancel相似,都是当前软件被挂起取消了授权,但是前者是用户不能控制的挂起,例如突然来了电话,电话应用进入前台,APP被挂起。后者是用户自己切到了别的应用,例如按home键挂起。LAErrorInvalidContext很好理解,就是授权过程中,LAContext对象被释放掉了,造成的授权失败。

//
//  ViewController.m
//  test_ touch_ID_01
//
//  Created by admin on 2/15/16.
//  Copyright © 2016 jeffasd. All rights reserved.
//

#import "ViewController.h"

#import <LocalAuthentication/LocalAuthentication.h>

@interface ViewController ()

@property(nonatomic, strong) UIButton *authority;
@property(nonatomic, strong) UIButton *entryButton;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    _authority = [UIButton buttonWithType:UIButtonTypeCustom];
    _authority.frame = CGRectMake(100, 100, 200, 50);
    _authority.backgroundColor = [UIColor cyanColor];
    
    [_authority setTitle:@"是否支持" forState:UIControlStateNormal];
    
    [_authority addTarget:self action:@selector(canEvaluatePolicy) forControlEvents:UIControlEventTouchUpInside];
    
    [self.view addSubview:_authority];
    
}

#pragma mark - evaluatePolicy
- (void)canEvaluatePolicy{
    
    LAContext *context = [LAContext new];
    __block NSString *message;
    NSError *error;
    BOOL success;
    
    success = [context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error];
    if (success) {
        message = [NSString stringWithFormat:@"Touch ID is available"];
    }else{
        message = [NSString stringWithFormat:@"Touch ID is not available"];
        NSLog(@"%@", message);
        
        switch (error.code) {
            case LAErrorTouchIDNotEnrolled:
                NSLog(@"TouchID is not enrolled");
                break;
                
            case LAErrorPasscodeNotSet:
                NSLog(@"A passcode has not been set");
                break;
                
            default:
                NSLog(@"TouchID not available");
                break;
        }
        
        NSLog(@"localized %@",error.localizedDescription);
    }
    
    NSLog(@"%@", message);
}

- (IBAction)entryButton:(UIButton *)sender {
    
    LAContext *context = [LAContext new];
    __block NSString *message;
    
    // Set text for the localized fallback button.
//    context.localizedFallbackTitle = @"Enter Password 111";
//    context.localizedFallbackTitle = @"111";
//    context.localizedFallbackTitle = @"";
    
    //show the authentication UI with our reason string
    [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"Unlock access to locked feature" reply:^(BOOL success, NSError * _Nullable authenticationError) {
        if (success) {
            //验证成功,主线程处理UI
            message = @"evaluatePolicy : success";
        }else{
            message = [NSString stringWithFormat:@"evaluatePolicy %@", authenticationError.localizedDescription];
            NSLog(@"%@", message);
            
            NSLog(@"%@",authenticationError.localizedDescription);
            switch (authenticationError.code) {
                case LAErrorSystemCancel:
                {
                    NSLog(@"Authentication was cancelled by the system");
                    //切换到其他APP,系统取消验证Touch ID
                    break;
                }
                case LAErrorUserCancel:
                {
                    NSLog(@"Authentication was cancelled by the user");
                    //用户取消验证Touch ID
                    break;
                }
                case LAErrorUserFallback:
                {
                    NSLog(@"User selected to enter custom password");
                    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                        //用户选择输入密码,切换主线程处理
                        UIView *view = [UIView new];
                        view.frame = self.view.bounds;
                        view.backgroundColor = [UIColor yellowColor];
                        
                        [self.view addSubview:view];
                    }];
                    break;
                }
                case LAErrorAuthenticationFailed:
                {
                    NSLog(@"User kLAErrorAuthenticationFailed");
                    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                        //用户选择输入密码,切换主线程处理
                    }];
                    break;
                }
                    
                default:
                {
                    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
                        //其他情况,切换主线程处理
                    }];
                    break;
                }
            }
        }
        
        NSLog(@"%@", message);
    }];
}









- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end