IOS开发-指纹识别

1. 简介

• iPhone 5S 开始支持
• iOS 8.0 开放了 Touch ID 的接口

2. 代码准备

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    [self inputUserinfo];
}

///  输入用户信息
- (void)inputUserinfo {
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"提示" message:@"购买" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"购买", nil];
    alertView.alertViewStyle = UIAlertViewStyleLoginAndPasswordInput;

    [alertView show];
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
    NSLog(@"%zd", buttonIndex);

    if (buttonIndex == 0) {
        return;
    }

    UITextField *usernameText = [alertView textFieldAtIndex:0];
    UITextField *pwdText = [alertView textFieldAtIndex:1];

    if ([usernameText.text isEqualToString:@"zhang"] && [pwdText.text isEqualToString:@"123"]) {
        [self purchase];
    } else {
        [[[UIAlertView alloc] initWithTitle:@"提示" message:@"用户名或密码错误" delegate:nil cancelButtonTitle:@"取消" otherButtonTitles:nil, nil] show];
    }
}

///  购买
- (void)purchase {
    NSLog(@"购买");
}

3. 指纹识别

头文件

#import <LocalAuthentication/LocalAuthentication.h>

判断是否支持指纹识别

// 检查版本
if ([UIDevice currentDevice].systemVersion.floatValue < 8.0) {
    [self inputUserinfo];
    return;
}

// 检查是否支持指纹识别
LAContext *ctx = [[LAContext alloc] init];

if ([ctx canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:NULL]) {
    NSLog(@"支持指纹识别");

    // 异步输入指纹
    [ctx evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:@"购买" reply:^(BOOL success, NSError *error) {
        NSLog(@"%d %@ %@", success, error, [NSThread currentThread]);
        if (success) {
            [self purchase];
        } else if (error.code == LAErrorUserFallback) {
            dispatch_async(dispatch_get_main_queue(), ^{
                [self inputUserinfo];
            });
        }
    }];
    NSLog(@"come here");
} else {
    [self inputUserinfo];
}

4. 错误代号