Can I maintain a single apk to handle fingerprint scanning on Android?

Question

While going through the Android Compatibility Definition for Android 6.0

I see the line: Device implementations with a secure lock screen SHOULD include a fingerprint sensor.

Does this mean I can't have a single version of my app which at runtime determines if the device has a finger print scanner or not? If it determines, that it has a scanner, it will launch the fingerprint scanning dialog else just ask for the PIN/Password.

Also can I use the same apk for Android versions lower than API 23?

Answer 1

You have to check

• device SDK version
• fingerprint hardware present

• fingerprint authentication ready (fingerprints already enrolled)

  if (Build.VERSION.SDK_INT < 23) {
      // Handle the mechanism where the SDK is older.
  }else{
      // Handle the mechanism where the SDK is 23 or later.
      FingerprintManager fingerprintManager = (FingerprintManager) context.getSystemService(Context.FINGERPRINT_SERVICE);
      if (!fingerprintManager.isHardwareDetected()) {
          // Device doesn't support fingerprint authentication     
      } else if (!fingerprintManager.hasEnrolledFingerprints()) {
          // User hasn't enrolled any fingerprints to authenticate with 
      } else {
          // Everything is ready for fingerprint authentication 
      }
  }