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      1 /*
      2  * Copyright (C) 2015 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License
     15  */
     16 
     17 package com.android.settings.fingerprint;
     18 
     19 import android.hardware.fingerprint.FingerprintManager;
     20 import android.os.CancellationSignal;
     21 import android.view.View;
     22 import android.widget.ImageView;
     23 import android.widget.TextView;
     24 
     25 import com.android.settings.R;
     26 import com.android.settings.Utils;
     27 
     28 /**
     29  * Small helper class to manage text/icon around fingerprint authentication UI.
     30  */
     31 public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallback {
     32 
     33     private static final long ERROR_TIMEOUT = 1300;
     34 
     35     private ImageView mIcon;
     36     private TextView mErrorTextView;
     37     private CancellationSignal mCancellationSignal;
     38     private int mUserId;
     39 
     40     private Callback mCallback;
     41     private FingerprintManager mFingerprintManager;
     42 
     43     public FingerprintUiHelper(ImageView icon, TextView errorTextView, Callback callback,
     44             int userId) {
     45         mFingerprintManager = Utils.getFingerprintManagerOrNull(icon.getContext());
     46         mIcon = icon;
     47         mErrorTextView = errorTextView;
     48         mCallback = callback;
     49         mUserId = userId;
     50     }
     51 
     52     public void startListening() {
     53         if (mFingerprintManager != null && mFingerprintManager.isHardwareDetected()
     54                 && mFingerprintManager.getEnrolledFingerprints(mUserId).size() > 0) {
     55             mCancellationSignal = new CancellationSignal();
     56             mFingerprintManager.setActiveUser(mUserId);
     57             mFingerprintManager.authenticate(
     58                     null, mCancellationSignal, 0 /* flags */, this, null, mUserId);
     59             setFingerprintIconVisibility(true);
     60             mIcon.setImageResource(R.drawable.ic_fingerprint);
     61         }
     62     }
     63 
     64     public void stopListening() {
     65         if (mCancellationSignal != null) {
     66             mCancellationSignal.cancel();
     67             mCancellationSignal = null;
     68         }
     69     }
     70 
     71     public boolean isListening() {
     72         return mCancellationSignal != null && !mCancellationSignal.isCanceled();
     73     }
     74 
     75     private void setFingerprintIconVisibility(boolean visible) {
     76         mIcon.setVisibility(visible ? View.VISIBLE : View.GONE);
     77         mCallback.onFingerprintIconVisibilityChanged(visible);
     78     }
     79 
     80     @Override
     81     public void onAuthenticationError(int errMsgId, CharSequence errString) {
     82         if (errMsgId == FingerprintManager.FINGERPRINT_ERROR_CANCELED) {
     83             // Only happens if we get preempted by another activity. Ignored.
     84             return;
     85         }
     86         showError(errString);
     87         setFingerprintIconVisibility(false);
     88     }
     89 
     90     @Override
     91     public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
     92         showError(helpString);
     93     }
     94 
     95     @Override
     96     public void onAuthenticationFailed() {
     97         showError(mIcon.getResources().getString(
     98                 R.string.fingerprint_not_recognized));
     99     }
    100 
    101     @Override
    102     public void onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result) {
    103         mIcon.setImageResource(R.drawable.ic_fingerprint_success);
    104         mCallback.onAuthenticated();
    105     }
    106 
    107     private void showError(CharSequence error) {
    108         if (!isListening()) {
    109             return;
    110         }
    111 
    112         mIcon.setImageResource(R.drawable.ic_fingerprint_error);
    113         mErrorTextView.setText(error);
    114         mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
    115         mErrorTextView.postDelayed(mResetErrorTextRunnable, ERROR_TIMEOUT);
    116     }
    117 
    118     private Runnable mResetErrorTextRunnable = new Runnable() {
    119         @Override
    120         public void run() {
    121             mErrorTextView.setText("");
    122             mIcon.setImageResource(R.drawable.ic_fingerprint);
    123         }
    124     };
    125 
    126     public interface Callback {
    127         void onAuthenticated();
    128         void onFingerprintIconVisibilityChanged(boolean visible);
    129     }
    130 }
    131