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.

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