iOS8使用TouchID

iOS8新增了LocalAuthentication框架，用于TouchID的授权使用。亲測，眼下须要用户的设备支持指纹识别并已设置锁屏，并且实际測试过程中反馈比較慢。不能直接跟第三方账号password绑定，假设须要实现第三方应用直接指纹识别登录，须要在本地存储账号信息，指纹识别通过之后再从本地读取账号信息登录。总之。眼下的指纹识别是跟设备、设备锁屏password绑定的。

測试代码：

///使用TouchID
-(void)usingTouchID
{
LAContext *myContext = [[[LAContext alloc] init] autorelease];
NSError *authError = nil;
NSString *myLocalizedReasonString = @"用于指纹登录";
if ([myContext canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&authError]) {
[myContext evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics
localizedReason:myLocalizedReasonString
reply:^(BOOL success, NSError *error) {
if (success) {
// User authenticated successfully, take appropriate action
NSLog(@"成功");
UIAlertView *alertView = [[[UIAlertView alloc] initWithTitle:@"Suceess" message:@"已通过指纹识别。" delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil] autorelease];
[alertView show];
} else {
// User did not authenticate successfully, look at error and take appropriate action
NSLog(@"fail with error:%@",error);
UIAlertView *alertView = [[[UIAlertView alloc] initWithTitle:@"Failed" message:[error localizedDescription] delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil] autorelease];
[alertView show];
}
}];
} else {
// Could not evaluate policy; look at authError and present an appropriate message to user
NSLog(@"auth with error:%@",authError);
UIAlertView *alertView = [[[UIAlertView alloc] initWithTitle:@"Failed" message:[authError localizedDescription] delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil] autorelease];
[alertView show];
}
}