/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License
*/
package com.example.android.fingerprintdialog;
import android.app.Activity;
import android.app.DialogFragment;
import android.content.SharedPreferences;
import android.hardware.fingerprint.FingerprintManager;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
/**
* A dialog which uses fingerprint APIs to authenticate the user, and falls back to password
* authentication if fingerprint is not available.
*/
public class FingerprintAuthenticationDialogFragment extends DialogFragment
implements TextView.OnEditorActionListener, FingerprintUiHelper.Callback {
private Button mCancelButton;
private Button mSecondDialogButton;
private View mFingerprintContent;
private View mBackupContent;
private EditText mPassword;
private CheckBox mUseFingerprintFutureCheckBox;
private TextView mPasswordDescriptionTextView;
private TextView mNewFingerprintEnrolledTextView;
private Stage mStage = Stage.FINGERPRINT;
private FingerprintManager.CryptoObject mCryptoObject;
private FingerprintUiHelper mFingerprintUiHelper;
private MainActivity mActivity;
private InputMethodManager mInputMethodManager;
private SharedPreferences mSharedPreferences;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Do not create a new Fragment when the Activity is re-created such as orientation changes.
setRetainInstance(true);
setStyle(DialogFragment.STYLE_NORMAL, android.R.style.Theme_Material_Light_Dialog);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
getDialog().setTitle(getString(R.string.sign_in));
View v = inflater.inflate(R.layout.fingerprint_dialog_container, container, false);
mCancelButton = (Button) v.findViewById(R.id.cancel_button);
mCancelButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
dismiss();
}
});
mSecondDialogButton = (Button) v.findViewById(R.id.second_dialog_button);
mSecondDialogButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mStage == Stage.FINGERPRINT) {
goToBackup();
} else {
verifyPassword();
}
}
});
mFingerprintContent = v.findViewById(R.id.fingerprint_container);
mBackupContent = v.findViewById(R.id.backup_container);
mPassword = (EditText) v.findViewById(R.id.password);
mPassword.setOnEditorActionListener(this);
mPasswordDescriptionTextView = (TextView) v.findViewById(R.id.password_description);
mUseFingerprintFutureCheckBox = (CheckBox)
v.findViewById(R.id.use_fingerprint_in_future_check);
mNewFingerprintEnrolledTextView = (TextView)
v.findViewById(R.id.new_fingerprint_enrolled_description);
mFingerprintUiHelper = new FingerprintUiHelper(
mActivity.getSystemService(FingerprintManager.class),
(ImageView) v.findViewById(R.id.fingerprint_icon),
(TextView) v.findViewById(R.id.fingerprint_status), this);
updateStage();
// If fingerprint authentication is not available, switch immediately to the backup
// (password) screen.
if (!mFingerprintUiHelper.isFingerprintAuthAvailable()) {
goToBackup();
}
return v;
}
@Override
public void onResume() {
super.onResume();
if (mStage == Stage.FINGERPRINT) {
mFingerprintUiHelper.startListening(mCryptoObject);
}
}
public void setStage(Stage stage) {
mStage = stage;
}
@Override
public void onPause() {
super.onPause();
mFingerprintUiHelper.stopListening();
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
mActivity = (MainActivity) activity;
mInputMethodManager = mActivity.getSystemService(InputMethodManager.class);
mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(mActivity);
}
/**
* Sets the crypto object to be passed in when authenticating with fingerprint.
*/
public void setCryptoObject(FingerprintManager.CryptoObject cryptoObject) {
mCryptoObject = cryptoObject;
}
/**
* Switches to backup (password) screen. This either can happen when fingerprint is not
* available or the user chooses to use the password authentication method by pressing the
* button. This can also happen when the user had too many fingerprint attempts.
*/
private void goToBackup() {
mStage = Stage.PASSWORD;
updateStage();
mPassword.requestFocus();
// Show the keyboard.
mPassword.postDelayed(mShowKeyboardRunnable, 500);
// Fingerprint is not used anymore. Stop listening for it.
mFingerprintUiHelper.stopListening();
}
/**
* Checks whether the current entered password is correct, and dismisses the the dialog and
* let's the activity know about the result.
*/
private void verifyPassword() {
if (!checkPassword(mPassword.getText().toString())) {
return;
}
if (mStage == Stage.NEW_FINGERPRINT_ENROLLED) {
SharedPreferences.Editor editor = mSharedPreferences.edit();
editor.putBoolean(getString(R.string.use_fingerprint_to_authenticate_key),
mUseFingerprintFutureCheckBox.isChecked());
editor.apply();
if (mUseFingerprintFutureCheckBox.isChecked()) {
// Re-create the key so that fingerprints including new ones are validated.
mActivity.createKey();
mStage = Stage.FINGERPRINT;
}
}
mPassword.setText("");
mActivity.onPurchased(false /* without Fingerprint */);
dismiss();
}
/**
* @return true if {@code password} is correct, false otherwise
*/
private boolean checkPassword(String password) {
// Assume the password is always correct.
// In the real world situation, the password needs to be verified in the server side.
return password.length() > 0;
}
private final Runnable mShowKeyboardRunnable = new Runnable() {
@Override
public void run() {
mInputMethodManager.showSoftInput(mPassword, 0);
}
};
private void updateStage() {
switch (mStage) {
case FINGERPRINT:
mCancelButton.setText(R.string.cancel);
mSecondDialogButton.setText(R.string.use_password);
mFingerprintContent.setVisibility(View.VISIBLE);
mBackupContent.setVisibility(View.GONE);
break;
case NEW_FINGERPRINT_ENROLLED:
// Intentional fall through
case PASSWORD:
mCancelButton.setText(R.string.cancel);
mSecondDialogButton.setText(R.string.ok);
mFingerprintContent.setVisibility(View.GONE);
mBackupContent.setVisibility(View.VISIBLE);
if (mStage == Stage.NEW_FINGERPRINT_ENROLLED) {
mPasswordDescriptionTextView.setVisibility(View.GONE);
mNewFingerprintEnrolledTextView.setVisibility(View.VISIBLE);
mUseFingerprintFutureCheckBox.setVisibility(View.VISIBLE);
}
break;
}
}
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_GO) {
verifyPassword();
return true;
}
return false;
}
@Override
public void onAuthenticated() {
// Callback from FingerprintUiHelper. Let the activity know that authentication was
// successful.
mActivity.onPurchased(true /* withFingerprint */);
dismiss();
}
@Override
public void onError() {
goToBackup();
}
/**
* Enumeration to indicate which authentication method the user is trying to authenticate with.
*/
public enum Stage {
FINGERPRINT,
NEW_FINGERPRINT_ENROLLED,
PASSWORD
}
}