Cannot read property 'isSensorAvailable' of undefined

[sagarmph]

I have encountered this below error after importing the package and trying to use it in my react native application. Request for the solution for below. The error is : Uncaught TypeError: Cannot read property 'isSensorAvailable' of undefined

I have tried with this both snippets from below, But unable to get the promise resolved or get the expected the expected console.

1. useEffect(() => { const rnBiometrics = new ReactNativeBiometrics(); rnBiometrics.isSensorAvailable().then((resultObject) => { const { available, biometryType } = resultObject;

   if (available && biometryType === BiometryTypes.TouchID) { console.log('TouchID is supported'); } else if (available && biometryType === BiometryTypes.FaceID) { console.log('FaceID is supported'); } else if (available && biometryType === BiometryTypes.Biometrics) { console.log('Biometrics is supported'); } else { console.log('Biometrics not supported'); } }); }, []);

2. const isBiometricSupport = async () => { let {available, biometryType} = await ReactNativeBiometrics.isSensorAvailable(); if (available && biometryType === ReactNativeBiometrics.TouchID) { console.log('TouchID is supported', biometryType); } else if (available && biometryType === ReactNativeBiometrics.FaceID) { console.log('FaceID is supported', biometryType); } else if (available && biometryType === ReactNativeBiometrics.Biometrics) { console.log('Biometrics is supported', biometryType); } else { console.log('Biometrics not supported', biometryType); } }; useEffect(() => { isBiometricSupport(); }, []);

React native version : >0.60.0 react-native-biometrics: 3.0.1 Trying to run on Android Phone in debug mode.

[Zcehtro]

I'm having the same issue. I tried using the examples provided in the README and then looked up a few tutorials and found the same one @sagarmph is following:

https://blog.logrocket.com/implementing-react-native-biometric-authentication-expo/#Using-react-native-biometrics

I'm always stuck with an unhandled promise rejection.

[sagarmph]

@Zcehtro The problem was with the package linking. I was able to use it when I had done the linking from the description of older version of package https://www.npmjs.com/package/react-native-biometrics/v/1.7.1

Also, Do pass the allowDeviceCredentials: true while initalizing. const rnBiometrics = new ReactNativeBiometrics({ allowDeviceCredentials: true })

[Zcehtro]

Thank you for your reply!

I think the problem in my situation is that I'm writing a React Native app using Expo. And the documentation for react-native-biometrics doesn't indicate if it's compatible with Expo or not.

From what I understand about what you shared, I'd need to run react-native link react-native-biometrics or it's equivalent in Expo... but Expo doesn't allow running react-native link and doesn't offer an equivalent.

How are you fairing with this?

[maniteja-emmadi]

I am getting a similar error saying [TypeError: Cannot read property 'isSensorAvailable' of null] for the exact same code that you've written except that I did not put the code snippet in useEffect I'm calling enableTouchId method on press of a TouchableOpacity

[asfaqehussain]

I got the solution for this.

You have to add allowDeviceCredentials in initialization

import ReactNativeBiometrics, { BiometryTypes } from 'react-native-biometrics'
 const rnBiometrics = new ReactNativeBiometrics({ allowDeviceCredentials: true })

       rnBiometrics.isSensorAvailable()
                .then((resultObject) => {
                    const { available, biometryType } = resultObject
                    console.log(' available ----> ', available);
                    console.log(' biometryType ----> ', biometryType);

                    if (available && biometryType === BiometryTypes.TouchID) {
                        console.log('TouchID is supported')
                    } else if (available && biometryType === BiometryTypes.FaceID) {
                        console.log('FaceID is supported')
                    } else if (available && biometryType === BiometryTypes.Biometrics) {
                        console.log('Biometrics is supported')
                    } else {
                        console.log('Biometrics not supported')
                    }
                })```

[hoanguyen3006]

I got the same error above on simulator Ios, but working on simualtor Android.

[hoanguyen3006]

I got the same error above on simulator Ios, but working on simualtor Android.

I have a solution. add <uses-permission android:name="android.permission.USE_FINGERPRINT"/> to AndroidManifest.xml for ANDROID add <key>NSFaceIDUsageDescription</key> <string>Enabling Face ID allows you quick and secure access to your account.</string> to Info.plist for IOS

[FoRavel]

The FaceID will work only if user has configured it on his device Settings.

If user has not configured is FaceID, it will fallback to the simple passcode verification (the code you enter to unlock your phone) when allowDeviceCredentials: true .

If you did not set allowDeviceCredientals to true and user has not enabled the FaceID on his phone of course, nothing will happen and new ReactNativeBiometrics(); will be undefined.

[hoanguyen3006]

The FaceID will work only if user has configured it on his device Settings.

If user has not configured is FaceID, it will fallback to the simple passcode verification (the code you enter to unlock your phone) when allowDeviceCredentials: true .

If you did not set allowDeviceCredientals to true and user has not enabled the FaceID on his phone of course, nothing will happen and new ReactNativeBiometrics(); will be undefined.

Thanks for reply, I have noted the problem.