Fingerprint Authentication Helper

Finger print authentication helper is an android library to simplify the authentication with finger print process. This will provide a common platform for finger print authentication for all the android versions.

##Screenshot

##Dependency

• Add the dependencies to your app level build.gradle file:

dependencies {
    compile 'com.multidots:fingerprint-auth:1.0.1'
}

##Usage

• Inside your activity or fragment create FingerPrintAuthHelper instance and call startAuth() in the onResume() to enable finger print scanning.

@Override
protected void onCreate(Bundle savedInstanceState) {
    mFingerPrintAuthHelper = FingerPrintAuthHelper.getHelper(this, this);
    //.... 
    //....        
}
   
@Override
protected void onResume() {
    super.onResume();
    //start finger print authentication
    mFingerPrintAuthHelper.startAuth();
}

• Don't forget to disable the finger print scanner in onPause() of your activity/fragment.

@Override
protected void onPause() {
    super.onPause();
    mFingerPrintAuthHelper.stopAuth();
}

Callbacks

• You need to implement FingerPrintAuthCallback in your activity/fragment to receive the callbacks from the helper class.

@Override
public void onNoFingerPrintHardwareFound() {
    //Device does not have finger print scanner.
}

@Override
public void onNoFingerPrintRegistered() {
    //There are no finger prints registered on this device.
}

@Override
public void onBelowMarshmallow() {
    //Device running below API 23 version of android that does not support finger print authentication.
}

@Override
public void onAuthSuccess(FingerprintManager.CryptoObject cryptoObject) {
    //Authentication sucessful.
}

@Override
public void onAuthFailed(int errorCode, String errorMessage) {
    switch (errorCode) {    //Parse the error code for recoverable/non recoverable error.
        case AuthErrorCodes.CANNOT_RECOGNIZE_ERROR:
            //Cannot recognize the fingerprint scanned.
            break;
        case AuthErrorCodes.NON_RECOVERABLE_ERROR:
            //This is not recoverable error. Try other options for user authentication. like pin, password.
            break;
        case AuthErrorCodes.RECOVERABLE_ERROR:
            //Any recoverable error. Display message to the user.
            break;
    }
}

##Demo application Here is the link to the demo application.

##Questions?

• If you have some problems with using this library or something doesn't work correctly, feel free to open an issue.

##How to contribute? ####Simple 3 step to contribute into this repo:

1. Fork the project.
2. Make required changes and commit.
3. Generate pull request. Mention all the required description regarding changes you made.

###Medium Article