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 
27 /**
28  * Small helper class to manage text/icon around fingerprint authentication UI.
29  */
30 public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallback {
31 
32     private static final long ERROR_TIMEOUT = 1300;
33 
34     private ImageView mIcon;
35     private TextView mErrorTextView;
36     private CancellationSignal mCancellationSignal;
37     private int mUserId;
38 
39     private Callback mCallback;
40     private FingerprintManager mFingerprintManager;
41 
FingerprintUiHelper(ImageView icon, TextView errorTextView, Callback callback, int userId)42     public FingerprintUiHelper(ImageView icon, TextView errorTextView, Callback callback,
43             int userId) {
44         mFingerprintManager = icon.getContext().getSystemService(FingerprintManager.class);
45         mIcon = icon;
46         mErrorTextView = errorTextView;
47         mCallback = callback;
48         mUserId = userId;
49     }
50 
startListening()51     public void startListening() {
52         if (mFingerprintManager != null && mFingerprintManager.isHardwareDetected()
53                 && mFingerprintManager.getEnrolledFingerprints(mUserId).size() > 0) {
54             mCancellationSignal = new CancellationSignal();
55             mFingerprintManager.setActiveUser(mUserId);
56             mFingerprintManager.authenticate(
57                     null, mCancellationSignal, 0 /* flags */, this, null, mUserId);
58             setFingerprintIconVisibility(true);
59             mIcon.setImageResource(R.drawable.ic_fingerprint);
60         }
61     }
62 
stopListening()63     public void stopListening() {
64         if (mCancellationSignal != null) {
65             mCancellationSignal.cancel();
66             mCancellationSignal = null;
67         }
68     }
69 
isListening()70     private boolean isListening() {
71         return mCancellationSignal != null && !mCancellationSignal.isCanceled();
72     }
73 
setFingerprintIconVisibility(boolean visible)74     private void setFingerprintIconVisibility(boolean visible) {
75         mIcon.setVisibility(visible ? View.VISIBLE : View.GONE);
76         mCallback.onFingerprintIconVisibilityChanged(visible);
77     }
78 
79     @Override
onAuthenticationError(int errMsgId, CharSequence errString)80     public void onAuthenticationError(int errMsgId, CharSequence errString) {
81         showError(errString);
82         setFingerprintIconVisibility(false);
83     }
84 
85     @Override
onAuthenticationHelp(int helpMsgId, CharSequence helpString)86     public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
87         showError(helpString);
88     }
89 
90     @Override
onAuthenticationFailed()91     public void onAuthenticationFailed() {
92         showError(mIcon.getResources().getString(
93                 R.string.fingerprint_not_recognized));
94     }
95 
96     @Override
onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result)97     public void onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result) {
98         mIcon.setImageResource(R.drawable.ic_fingerprint_success);
99         mCallback.onAuthenticated();
100     }
101 
showError(CharSequence error)102     private void showError(CharSequence error) {
103         if (!isListening()) {
104             return;
105         }
106 
107         mIcon.setImageResource(R.drawable.ic_fingerprint_error);
108         mErrorTextView.setText(error);
109         mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
110         mErrorTextView.postDelayed(mResetErrorTextRunnable, ERROR_TIMEOUT);
111     }
112 
113     private Runnable mResetErrorTextRunnable = new Runnable() {
114         @Override
115         public void run() {
116             mErrorTextView.setText("");
117             mIcon.setImageResource(R.drawable.ic_fingerprint);
118         }
119     };
120 
121     public interface Callback {
onAuthenticated()122         void onAuthenticated();
onFingerprintIconVisibilityChanged(boolean visible)123         void onFingerprintIconVisibilityChanged(boolean visible);
124     }
125 }
126