Move fingerprint enroll logic into sidecar fragment

So enroll can continue across configuration changes.

Bug: 20495507
Change-Id: I021f2f3e376fcd12c7a698f5fb7f862733cb720a
(cherry picked from commit 64e9c4cb2c)

src/com/android/settings/fingerprint/FingerprintEnrollSidecar.java

@@ -0,0 +1,157 @@
+/*
+ * 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.android.settings.fingerprint;
+
+import android.annotation.Nullable;
+import android.app.Activity;
+import android.app.Fragment;
+import android.hardware.fingerprint.FingerprintManager;
+import android.os.Bundle;
+import android.os.CancellationSignal;
+import android.os.Handler;
+import android.os.PowerManager;
+import android.os.SystemClock;
+
+import com.android.settings.ChooseLockSettingsHelper;
+
+/**
+ * Sidecar fragment to handle the state around fingerprint enrollment.
+ */
+public class FingerprintEnrollSidecar extends Fragment {
+
+    private int mEnrollmentSteps = -1;
+    private int mEnrollmentRemaining = 0;
+    private Listener mListener;
+    private PowerManager mPowerManager;
+    private boolean mEnrolling;
+    private CancellationSignal mEnrollmentCancel;
+    private Handler mHandler = new Handler();
+    private byte[] mToken;
+    private boolean mDone;
+
+    @Override
+    public void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setRetainInstance(true);
+    }
+
+    @Override
+    public void onAttach(Activity activity) {
+        super.onAttach(activity);
+        mPowerManager = activity.getSystemService(PowerManager.class);
+        mToken = activity.getIntent().getByteArrayExtra(
+                ChooseLockSettingsHelper.EXTRA_KEY_CHALLENGE_TOKEN);
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
+        if (!mEnrolling) {
+            startEnrollment();
+        }
+    }
+
+    @Override
+    public void onStop() {
+        super.onStop();
+        if (!getActivity().isChangingConfigurations()) {
+            cancelEnrollment();
+        }
+    }
+
+    private void startEnrollment() {
+        mHandler.removeCallbacks(mTimeoutRunnable);
+        mEnrollmentSteps = -1;
+        mEnrollmentCancel = new CancellationSignal();
+        getActivity().getSystemService(FingerprintManager.class).enroll(mToken, mEnrollmentCancel,
+                mEnrollmentCallback, 0);
+        mEnrolling = true;
+    }
+
+    private void cancelEnrollment() {
+        mHandler.removeCallbacks(mTimeoutRunnable);
+        if (mEnrolling) {
+            mEnrollmentCancel.cancel();
+            mEnrolling = false;
+            mEnrollmentSteps = -1;
+        }
+    }
+
+    public void setListener(Listener listener) {
+        mListener = listener;
+    }
+
+    public int getEnrollmentSteps() {
+        return mEnrollmentSteps;
+    }
+
+    public int getEnrollmentRemaining() {
+        return mEnrollmentRemaining;
+    }
+
+    public boolean isDone() {
+        return mDone;
+    }
+
+    private FingerprintManager.EnrollmentCallback mEnrollmentCallback
+            = new FingerprintManager.EnrollmentCallback() {
+
+        @Override
+        public void onEnrollmentProgress(int remaining) {
+            if (mEnrollmentSteps == -1) {
+                mEnrollmentSteps = remaining;
+            }
+            mEnrollmentRemaining = remaining;
+            mDone = remaining == 0;
+            if (mListener != null) {
+                mListener.onEnrollmentProgressChange(mEnrollmentSteps, remaining);
+            }
+
+            // Treat fingerprint like a touch event
+            mPowerManager.userActivity(SystemClock.uptimeMillis(),
+                    PowerManager.USER_ACTIVITY_EVENT_OTHER,
+                    PowerManager.USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS);
+        }
+
+        @Override
+        public void onEnrollmentHelp(int helpMsgId, CharSequence helpString) {
+            if (mListener != null) {
+                mListener.onEnrollmentHelp(helpString);
+            }
+        }
+
+        @Override
+        public void onEnrollmentError(int errMsgId, CharSequence errString) {
+            if (mListener != null) {
+                mListener.onEnrollmentError(errString);
+            }
+        }
+    };
+
+    private final Runnable mTimeoutRunnable = new Runnable() {
+        @Override
+        public void run() {
+            cancelEnrollment();
+        }
+    };
+
+    public interface Listener {
+        void onEnrollmentHelp(CharSequence helpString);
+        void onEnrollmentError(CharSequence errString);
+        void onEnrollmentProgressChange(int steps, int remaining);
+    }
+}