com.github.brandon.fingerprintauthenticationdialog.FingerprintUiHelper.java Source code

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Here is the source code for com.github.brandon.fingerprintauthenticationdialog.FingerprintUiHelper.java

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/*
 * 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.github.brandon.fingerprintauthenticationdialog;

import android.Manifest;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.pm.PackageManager;
import android.hardware.fingerprint.FingerprintManager;
import android.os.Build;
import android.os.CancellationSignal;
import android.support.v4.content.ContextCompat;
import android.widget.ImageView;
import android.widget.TextView;

/**
 * Small helper class to manage text/icon around fingerprint authentication UI.
 */
@TargetApi(Build.VERSION_CODES.M)
public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallback {

    static final long ERROR_TIMEOUT_MILLIS = 1000;
    static final long SUCCESS_DELAY_MILLIS = 1000;

    private final FingerprintManager mFingerprintManager;
    private final ImageView mIcon;
    private final TextView mErrorTextView;
    private final FingerprintCallback mCallback;
    private CancellationSignal mCancellationSignal;
    private Activity mActivity;

    /**
     * Builder class for {@link FingerprintUiHelper} in which injected fields from Dagger
     * holds its fields and takes other arguments in the {@link #build} method.
     */
    public static class FingerprintUiHelperBuilder {
        private final FingerprintManager mFingerPrintManager;

        public FingerprintUiHelperBuilder(FingerprintManager fingerprintManager) {
            mFingerPrintManager = fingerprintManager;
        }

        public FingerprintUiHelper build(Activity activity, ImageView icon, TextView errorTextView,
                FingerprintCallback callback) {
            return new FingerprintUiHelper(activity, mFingerPrintManager, icon, errorTextView, callback);
        }
    }

    /**
     * Constructor for {@link FingerprintUiHelper}. This method is expected to be called from
     * only the {@link FingerprintUiHelperBuilder} class.
     */
    private FingerprintUiHelper(Activity activity, FingerprintManager fingerprintManager, ImageView icon,
            TextView errorTextView, FingerprintCallback callback) {
        mActivity = activity;
        mFingerprintManager = fingerprintManager;
        mIcon = icon;
        mErrorTextView = errorTextView;
        mCallback = callback;
    }

    public void startListening(FingerprintManager.CryptoObject cryptoObject) {
        if (cryptoObject == null)
            return;
        mCancellationSignal = new CancellationSignal();
        if (ContextCompat.checkSelfPermission(mActivity,
                Manifest.permission.USE_FINGERPRINT) == PackageManager.PERMISSION_GRANTED) {
            mFingerprintManager.authenticate(cryptoObject, mCancellationSignal, 0 /* flags */, this, null);
        }
        mIcon.setImageResource(R.drawable.ic_fp_40px);
    }

    public void stopListening() {
        if (mCancellationSignal != null) {
            mCancellationSignal.cancel();
            mCancellationSignal = null;
        }
    }

    @Override
    public void onAuthenticationError(final int errMsgId, CharSequence errString) {
        showError(errString);
        mIcon.postDelayed(new Runnable() {
            @Override
            public void run() {
                mCallback.onError(errMsgId);
            }
        }, ERROR_TIMEOUT_MILLIS);
    }

    @Override
    public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
        showError(helpString);
    }

    @Override
    public void onAuthenticationFailed() {
        showError(mIcon.getResources().getString(R.string.fingerprint_not_recognized));
    }

    @Override
    public void onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result) {
        mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
        mIcon.setImageResource(R.drawable.ic_fingerprint_success);
        mErrorTextView
                .setTextColor(mErrorTextView.getResources().getColor(R.color.fingerprint_success_color, null));
        mErrorTextView.setText(mErrorTextView.getResources().getString(R.string.fingerprint_success));
        mIcon.postDelayed(new Runnable() {
            @Override
            public void run() {
                mCallback.onAuthenticated();
            }
        }, SUCCESS_DELAY_MILLIS);
    }

    private void showError(CharSequence error) {
        mIcon.setImageResource(R.drawable.ic_fingerprint_error);
        mErrorTextView.setText(error);
        mErrorTextView
                .setTextColor(mErrorTextView.getResources().getColor(R.color.fingerprint_warning_color, null));
        mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
        mErrorTextView.postDelayed(mResetErrorTextRunnable, ERROR_TIMEOUT_MILLIS);
    }

    Runnable mResetErrorTextRunnable = new Runnable() {
        @Override
        public void run() {
            mErrorTextView
                    .setTextColor(mErrorTextView.getResources().getColor(R.color.fingerprint_hint_color, null));
            mErrorTextView.setText(mErrorTextView.getResources().getString(R.string.fingerprint_hint));
            mIcon.setImageResource(R.drawable.ic_fp_40px);
        }
    };
}