Check for sidecar null-ness before removing

Test: cd tests/robotests && mma
Bug: 36681116
Change-Id: Id48113502c538b607d92700d3e58943614cfc150
diff --git a/src/com/android/settings/Utils.java b/src/com/android/settings/Utils.java
index f6f980a..0142ea2 100644
--- a/src/com/android/settings/Utils.java
+++ b/src/com/android/settings/Utils.java
@@ -103,6 +103,8 @@
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.UserIcons;
 import com.android.internal.widget.LockPatternUtils;
+import com.android.settings.password.FingerprintManagerWrapper;
+import com.android.settings.password.IFingerprintManager;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -1197,6 +1199,15 @@
         }
     }
 
+    public static IFingerprintManager getFingerprintManagerWrapperOrNull(Context context) {
+        FingerprintManager fingerprintManager = getFingerprintManagerOrNull(context);
+        if (fingerprintManager != null) {
+            return new FingerprintManagerWrapper(fingerprintManager);
+        } else {
+            return null;
+        }
+    }
+
     /**
      * Launches an intent which may optionally have a user id defined.
      * @param fragment Fragment to use to launch the activity.
diff --git a/src/com/android/settings/fingerprint/FingerprintEnrollFindSensor.java b/src/com/android/settings/fingerprint/FingerprintEnrollFindSensor.java
index 510e953..107838c 100644
--- a/src/com/android/settings/fingerprint/FingerprintEnrollFindSensor.java
+++ b/src/com/android/settings/fingerprint/FingerprintEnrollFindSensor.java
@@ -82,9 +82,7 @@
             @Override
             public void onEnrollmentProgressChange(int steps, int remaining) {
                 mNextClicked = true;
-                if (!mSidecar.cancelEnrollment()) {
-                    proceedToEnrolling();
-                }
+                proceedToEnrolling(true /* cancelEnrollment */);
             }
 
             @Override
@@ -95,7 +93,7 @@
             public void onEnrollmentError(int errMsgId, CharSequence errString) {
                 if (mNextClicked && errMsgId == FingerprintManager.FINGERPRINT_ERROR_CANCELED) {
                     mNextClicked = false;
-                    proceedToEnrolling();
+                    proceedToEnrolling(false /* cancelEnrollment */);
                 }
             }
         });
@@ -123,15 +121,23 @@
     @Override
     protected void onNextButtonClick() {
         mNextClicked = true;
-        if (mSidecar == null || (mSidecar != null && !mSidecar.cancelEnrollment())) {
-            proceedToEnrolling();
-        }
+        proceedToEnrolling(true /* cancelEnrollment */);
     }
 
-    private void proceedToEnrolling() {
-        getFragmentManager().beginTransaction().remove(mSidecar).commit();
-        mSidecar = null;
-        startActivityForResult(getEnrollingIntent(), ENROLLING);
+    private void proceedToEnrolling(boolean cancelEnrollment) {
+        if (mSidecar != null) {
+            if (cancelEnrollment) {
+                if (mSidecar.cancelEnrollment()) {
+                    // Enrollment cancel requested. When the cancellation is successful,
+                    // onEnrollmentError will be called with FINGERPRINT_ERROR_CANCELED, calling
+                    // this again.
+                    return;
+                }
+            }
+            getFragmentManager().beginTransaction().remove(mSidecar).commit();
+            mSidecar = null;
+            startActivityForResult(getEnrollingIntent(), ENROLLING);
+        }
     }
 
     @Override
diff --git a/src/com/android/settings/fingerprint/FingerprintEnrollSidecar.java b/src/com/android/settings/fingerprint/FingerprintEnrollSidecar.java
index e0c5d65..7fc7a04 100644
--- a/src/com/android/settings/fingerprint/FingerprintEnrollSidecar.java
+++ b/src/com/android/settings/fingerprint/FingerprintEnrollSidecar.java
@@ -28,12 +28,13 @@
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
 import com.android.settings.ChooseLockSettingsHelper;
 import com.android.settings.Utils;
-import com.android.settings.core.InstrumentedPreferenceFragment;
+import com.android.settings.core.InstrumentedFragment;
+import com.android.settings.password.IFingerprintManager;
 
 /**
  * Sidecar fragment to handle the state around fingerprint enrollment.
  */
-public class FingerprintEnrollSidecar extends InstrumentedPreferenceFragment {
+public class FingerprintEnrollSidecar extends InstrumentedFragment {
 
     private int mEnrollmentSteps = -1;
     private int mEnrollmentRemaining = 0;
@@ -44,7 +45,7 @@
     private byte[] mToken;
     private boolean mDone;
     private int mUserId;
-    private FingerprintManager mFingerprintManager;
+    private IFingerprintManager mFingerprintManager;
 
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
@@ -55,7 +56,7 @@
     @Override
     public void onAttach(Activity activity) {
         super.onAttach(activity);
-        mFingerprintManager = Utils.getFingerprintManagerOrNull(activity);
+        mFingerprintManager = Utils.getFingerprintManagerWrapperOrNull(activity);
         mToken = activity.getIntent().getByteArrayExtra(
                 ChooseLockSettingsHelper.EXTRA_KEY_CHALLENGE_TOKEN);
         mUserId = activity.getIntent().getIntExtra(Intent.EXTRA_USER_ID, UserHandle.USER_NULL);
diff --git a/src/com/android/settings/password/FingerprintManagerWrapper.java b/src/com/android/settings/password/FingerprintManagerWrapper.java
index b00f786..51b31af 100644
--- a/src/com/android/settings/password/FingerprintManagerWrapper.java
+++ b/src/com/android/settings/password/FingerprintManagerWrapper.java
@@ -18,6 +18,8 @@
 
 import android.annotation.NonNull;
 import android.hardware.fingerprint.FingerprintManager;
+import android.hardware.fingerprint.FingerprintManager.EnrollmentCallback;
+import android.os.CancellationSignal;
 
 import com.android.internal.util.Preconditions;
 
@@ -33,15 +35,33 @@
         mFingerprintManager = fingerprintManager;
     }
 
+    @Override
     public boolean isHardwareDetected() {
         return mFingerprintManager.isHardwareDetected();
     }
 
+    @Override
     public boolean hasEnrolledFingerprints(int userId) {
         return mFingerprintManager.hasEnrolledFingerprints(userId);
     }
 
+    @Override
     public long preEnroll() {
         return mFingerprintManager.preEnroll();
     }
+
+    @Override
+    public void setActiveUser(int userId) {
+        mFingerprintManager.setActiveUser(userId);
+    }
+
+    @Override
+    public void enroll(
+            byte[] token,
+            CancellationSignal cancel,
+            int flags,
+            int userId,
+            EnrollmentCallback callback) {
+        mFingerprintManager.enroll(token, cancel, flags, userId, callback);
+    }
 }
diff --git a/src/com/android/settings/password/IFingerprintManager.java b/src/com/android/settings/password/IFingerprintManager.java
index 15a9242..9402146 100644
--- a/src/com/android/settings/password/IFingerprintManager.java
+++ b/src/com/android/settings/password/IFingerprintManager.java
@@ -16,6 +16,9 @@
 
 package com.android.settings.password;
 
+import android.hardware.fingerprint.FingerprintManager.EnrollmentCallback;
+import android.os.CancellationSignal;
+
 /**
  * This is the workaround to allow us test {@link SetNewPasswordController} which uses a new hidden
  * API {@link android.hardware.fingerprint.FingerprintManager#hasEnrolledFingerprints(int)} that
@@ -28,4 +31,9 @@
     boolean hasEnrolledFingerprints(int userId);
 
     long preEnroll();
+
+    void setActiveUser(int userId);
+
+    void enroll(byte [] token, CancellationSignal cancel, int flags,
+            int userId, EnrollmentCallback callback);
 }