How to use android.support.v4.hardware.fingerprint

  return;
FingerprintManagerCompat managerCompat = FingerprintManagerCompat.from(context);
if (!managerCompat.isHardwareDetected()) { //判断设备是否支持
  if (listener != null)
    listener.onSupportFailed();
if (!managerCompat.hasEnrolledFingerprints()) { //判断设备是否已经注册过指纹
  if (listener != null)
managerCompat.authenticate(null, 0, cancellationSignal, new FingerprintManagerCompat.AuthenticationCallback() {

public boolean isFingerprintAuthAvailable() {
  // The line below prevents the false positive inspection from Android Studio
  // noinspection ResourceType
  return mFingerprintManager.isHardwareDetected()
      && mFingerprintManager.hasEnrolledFingerprints();
}

  /**
   * Check if the device have supported hardware fir the finger print scanner.
   *
   * @param context instance of the caller.
   * @return true if device have the hardware.
   */
  public static boolean isSupportedHardware(Context context) {
    FingerprintManagerCompat fingerprintManager = FingerprintManagerCompat.from(context);
    return fingerprintManager.isHardwareDetected();
  }
}

/**
 * Check if the finger print hardware is available.
 *
 * @param context instance of the caller.
 * @return true if finger print authentication is supported.
 */
private boolean checkFingerPrintAvailability(@NonNull Context context) {
  // Check if we're running on Android 6.0 (M) or higher
  if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    //Fingerprint API only available on from Android 6.0 (M)
    FingerprintManagerCompat fingerprintManager = FingerprintManagerCompat.from(context);
    if (!fingerprintManager.isHardwareDetected()) {
      // Device doesn't support fingerprint authentication
      mCallback.onNoFingerPrintHardwareFound();
      return false;
    } else if (!fingerprintManager.hasEnrolledFingerprints()) {
      // User hasn't enrolled any fingerprints to authenticate with
      mCallback.onNoFingerPrintRegistered();
      return false;
    }
    return true;
  } else {
    mCallback.onBelowMarshmallow();
    return false;
  }
}

private boolean isFingerPrintReady(Context context) {
  return FingerprintManagerCompat.from(context).hasEnrolledFingerprints();
}

@Provides
public FingerprintManagerCompat providesFingerprintManager(Context context) {
  return FingerprintManagerCompat.from(context);
}

public void startListening(FingerprintManagerCompat.CryptoObject cryptoObject) {
  if (!isFingerprintAuthAvailable()) {
    return;
  }
  mCancellationSignal = new CancellationSignal();
  mSelfCancelled = false;
  // The line below prevents the false positive inspection from Android Studio
  // noinspection ResourceType
  mFingerprintManager.authenticate(
      cryptoObject, 0, mCancellationSignal, this, null);
  mIcon.setImageResource(R.drawable.ic_fp_40px_pf);
}

public FingerprintManagerCompat.CryptoObject buildCryptoObject() throws Exception
{
  Cipher cipher = createCipher(true);
  return new FingerprintManagerCompat.CryptoObject(cipher);
}

@Override
public void onAuthenticationError(int errMsgId, CharSequence errString) {
  super.onAuthenticationError(errMsgId, errString);
  if (handler != null) {
    handler.obtainMessage(MainActivity.MSG_AUTH_ERROR, errMsgId, 0).sendToTarget();
  }
}

@Override
public void onAuthenticationSucceeded(FingerprintManagerCompat.AuthenticationResult result) {
  super.onAuthenticationSucceeded(result);
  if (handler != null) {
    handler.obtainMessage(MainActivity.MSG_AUTH_SUCCESS).sendToTarget();
  }
}

@Override
public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
  super.onAuthenticationHelp(helpMsgId, helpString);
  if (handler != null) {
    handler.obtainMessage(MainActivity.MSG_AUTH_HELP, helpMsgId, 0).sendToTarget();
  }
}

  @Override
  public void onAuthenticationFailed() {
    super.onAuthenticationFailed();

    if (handler != null) {
      handler.obtainMessage(MainActivity.MSG_AUTH_FAILED).sendToTarget();
    }
  }
}

private boolean isFingerprintApiAvailable(Context context) {
  return FingerprintManagerCompat.from(context).isHardwareDetected();
}

public boolean isFingerprintAuthAvailable() {
  return mFingerprintManager.isHardwareDetected()
      && mFingerprintManager.hasEnrolledFingerprints();
}

private boolean isFingerprintsExists(Context context) {
  return FingerprintManagerCompat.from(context).hasEnrolledFingerprints();
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
             Bundle savedInstanceState) {
  getDialog().setTitle(getString(R.string.sign_in_pf));
  View v = inflater.inflate(R.layout.view_pf_fingerprint_dialog_container, container,
      false);
  mCancelButton = v.findViewById(R.id.cancel_button);
  mCancelButton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
      dismiss();
    }
  });
  mFingerprintContent = v.findViewById(R.id.fingerprint_container);
  FingerprintManagerCompat manager = FingerprintManagerCompat.from(getContext());
  mFingerprintCallback = new PFFingerprintUIHelper(manager,
      (ImageView) v.findViewById(R.id.fingerprint_icon),
      (TextView) v.findViewById(R.id.fingerprint_status),
      mAuthListener);
  updateStage();
  return v;
}

public void startListening(FingerprintManagerCompat.CryptoObject cryptoObject) {
  if (!isFingerprintAuthAvailable()) {
    return;
  }
  mCancellationSignal = new CancellationSignal();
  mSelfCancelled = false;
  mFingerprintManager
      .authenticate(cryptoObject, 0 /* flags */, mCancellationSignal, this, null);
  mIcon.setImageResource(R.drawable.ic_fp_40px);
}

  @Override
  public void onClick(View v) {
    findViewById(R.id.confirmation_message).setVisibility(View.GONE);
    findViewById(R.id.encrypted_message).setVisibility(View.GONE);
    // 署名クラスが初期化できたら認証ダイアログを出します。
    if (initSignature()) {
      mFragment.setCryptoObject(new FingerprintManagerCompat.CryptoObject(mSignature));
      boolean useFingerprintPreference = mSharedPreferences.getBoolean(getString(R.string.use_fingerprint_to_authenticate_key), true);
      if (useFingerprintPreference) {
        mFragment.setStage(FingerprintAuthenticationDialogFragment.Stage.FINGERPRINT);
      } else {
        mFragment.setStage(FingerprintAuthenticationDialogFragment.Stage.PASSWORD);
      }
      mFragment.show(getFragmentManager(), DIALOG_FRAGMENT_TAG);
    } else {
      // 鍵のペアを生成後、ロック画面が無効になった場合、もしくは鍵のペアを生成後、新たに指紋が登録された場合
      mFragment.setStage(FingerprintAuthenticationDialogFragment.Stage.NEW_FINGERPRINT_ENROLLED);
      mFragment.show(getFragmentManager(), DIALOG_FRAGMENT_TAG);
    }
  }
});

private boolean isFingerPrintAvailable(Context context) {
  return FingerprintManagerCompat.from(context).isHardwareDetected();
}

  @Override
  public void onClick(View v) {
    // reset result info.
    mResultInfo.setText(R.string.fingerprint_hint);
    mResultInfo.setTextColor(getColor(R.color.hint_color));
    // start fingerprint auth here.
    try {
      CryptoObjectHelper cryptoObjectHelper = new CryptoObjectHelper();
      if (cancellationSignal == null) {
        cancellationSignal = new CancellationSignal();
      }
      fingerprintManager.authenticate(cryptoObjectHelper.buildCryptoObject(), 0,
          cancellationSignal, myAuthCallback, null);
      // set button state.
      mStartBtn.setEnabled(false);
      mCancelBtn.setEnabled(true);
    } catch (Exception e) {
      e.printStackTrace();
      Toast.makeText(MainActivity.this, "Fingerprint init failed! Try again!", Toast.LENGTH_SHORT).show();
    }
  }
});