Check FingerprintManager null

app/src/main/java/com/hippo/ehviewer/ui/SetSecurityActivity.java

@@ -62,7 +62,7 @@ public class SetSecurityActivity extends ToolbarActivity implements View.OnClick
             FingerprintManager fingerprintManager = getSystemService(FingerprintManager.class);
             // The line below prevents the false positive inspection from Android Studio
             // noinspection ResourceType
-            if (fingerprintManager.hasEnrolledFingerprints()) {
+            if (fingerprintManager != null && fingerprintManager.hasEnrolledFingerprints()) {
                 mFingerprint.setVisibility(View.VISIBLE);
                 mFingerprint.setChecked(Settings.getEnableFingerprint());
             }

app/src/main/java/com/hippo/ehviewer/ui/scene/SecurityScene.java

@@ -55,6 +55,7 @@ public class SecurityScene extends SolidScene implements
     private SensorManager mSensorManager;
     private Sensor mAccelerometer;
     private ShakeDetector mShakeDetector;
+    @Nullable
     private FingerprintManager mFingerprintManager;
 
     private CancellationSignal mFingerprintCancellationSignal;