diff --git a/wear/src/main/java/info/nightscout/androidaps/complications/BaseComplicationProviderService.java b/wear/src/main/java/info/nightscout/androidaps/complications/BaseComplicationProviderService.java
index 0db70ad7e1..c7648bed92 100644
--- a/wear/src/main/java/info/nightscout/androidaps/complications/BaseComplicationProviderService.java
+++ b/wear/src/main/java/info/nightscout/androidaps/complications/BaseComplicationProviderService.java
@@ -13,6 +13,8 @@ import android.support.wearable.complications.ComplicationProviderService;
 import android.support.wearable.complications.ComplicationText;
 import android.support.wearable.complications.ProviderUpdateRequester;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 
 import java.util.HashSet;
@@ -67,9 +69,9 @@ public abstract class BaseComplicationProviderService extends ComplicationProvid
     // ABSTRACT COMPLICATION INTERFACE
     //==============================================================================================
 
-    public abstract ComplicationData buildComplicationData(int dataType, RawDisplayData raw, PendingIntent complicationPendingIntent);
+    public abstract @Nullable ComplicationData buildComplicationData(int dataType, RawDisplayData raw, PendingIntent complicationPendingIntent);
 
-    public abstract String getProviderCanonicalName();
+    public abstract @NonNull String getProviderCanonicalName();
 
     public ComplicationAction getComplicationAction() {
         return ComplicationAction.MENU;
diff --git a/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.java b/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.java
deleted file mode 100644
index 8934a8df2d..0000000000
--- a/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.java
+++ /dev/null
@@ -1,58 +0,0 @@
-package info.nightscout.androidaps.complications;
-
-import android.app.PendingIntent;
-import android.support.wearable.complications.ComplicationData;
-import android.support.wearable.complications.ComplicationText;
-
-import javax.inject.Inject;
-
-import dagger.android.AndroidInjection;
-import info.nightscout.androidaps.data.RawDisplayData;
-import info.nightscout.androidaps.interaction.utils.DisplayFormat;
-import info.nightscout.shared.logging.LTag;
-
-/*
- * Created by dlvoy on 2019-11-12
- */
-@SuppressWarnings("deprecation")
-public class SgvComplication extends BaseComplicationProviderService {
-
-    @Inject DisplayFormat displayFormat;
-
-    // Not derived from DaggerService, do injection here
-    @Override
-    public void onCreate() {
-        AndroidInjection.inject(this);
-        super.onCreate();
-    }
-
-    public ComplicationData buildComplicationData(int dataType, RawDisplayData raw, PendingIntent complicationPendingIntent) {
-
-        ComplicationData complicationData = null;
-
-        switch (dataType) {
-            case ComplicationData.TYPE_SHORT_TEXT:
-                final ComplicationData.Builder builder = new ComplicationData.Builder(ComplicationData.TYPE_SHORT_TEXT)
-                        .setShortText(ComplicationText.plainText(raw.getSingleBg().getSgvString() + raw.getSingleBg().getSlopeArrow() +
-                                "\uFE0E"))
-                        .setShortTitle(ComplicationText.plainText(displayFormat.shortTrend(raw)))
-                        .setTapAction(complicationPendingIntent);
-
-                complicationData = builder.build();
-                break;
-            default:
-                aapsLogger.warn(LTag.WEAR, "Unexpected complication type " + dataType);
-        }
-        return complicationData;
-    }
-
-    @Override
-    public String getProviderCanonicalName() {
-        return SgvComplication.class.getCanonicalName();
-    }
-
-    @Override
-    protected boolean usesSinceField() {
-        return true;
-    }
-}
diff --git a/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.kt b/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.kt
new file mode 100644
index 0000000000..b692eeb17d
--- /dev/null
+++ b/wear/src/main/java/info/nightscout/androidaps/complications/SgvComplication.kt
@@ -0,0 +1,41 @@
+@file:Suppress("DEPRECATION")
+
+package info.nightscout.androidaps.complications
+
+import android.app.PendingIntent
+import android.support.wearable.complications.ComplicationData
+import android.support.wearable.complications.ComplicationText
+import dagger.android.AndroidInjection
+import info.nightscout.androidaps.data.RawDisplayData
+import info.nightscout.shared.logging.LTag
+
+/*
+ * Created by dlvoy on 2019-11-12
+ */
+class SgvComplication : BaseComplicationProviderService() {
+
+    // Not derived from DaggerService, do injection here
+    override fun onCreate() {
+        AndroidInjection.inject(this)
+        super.onCreate()
+    }
+
+    override fun buildComplicationData(dataType: Int, raw: RawDisplayData, complicationPendingIntent: PendingIntent): ComplicationData? {
+        var complicationData: ComplicationData? = null
+        when (dataType) {
+            ComplicationData.TYPE_SHORT_TEXT -> {
+                val builder = ComplicationData.Builder(ComplicationData.TYPE_SHORT_TEXT)
+                    .setShortText(ComplicationText.plainText(raw.singleBg.sgvString + raw.singleBg.slopeArrow + "\uFE0E"))
+                    .setShortTitle(ComplicationText.plainText(displayFormat.shortTrend(raw)))
+                    .setTapAction(complicationPendingIntent)
+                complicationData = builder.build()
+            }
+
+            else                             -> aapsLogger.warn(LTag.WEAR, "Unexpected complication type $dataType")
+        }
+        return complicationData
+    }
+
+    override fun getProviderCanonicalName(): String = SgvComplication::class.java.canonicalName!!
+    override fun usesSinceField(): Boolean = true
+}
\ No newline at end of file