Elevation gain: make it optional as Float.

So if no sensor data is provided, it is not stored in the database and not exported.

src/androidTest/java/de/dennisguse/opentracks/services/sensors/ElevationSumManagerTest.java

@@ -24,6 +24,9 @@ public class ElevationSumManagerTest {
 
     @Test
     public void getElevationGainLoss_downhill() {
+        // given
+        elevationSumManager.setConnected(true);
+
         // then
         addSensorValue(elevationSumManager, new float[]{1015f, 1015.01f, 1015.02f, 1015.03f, 1015.04f, 1015.05f, 1015.06f, 1015.07f, 1015.08f, 1015.09f, 1015.10f, 1015.11f, 1015.12f, 1015.13f, 1015.14f, 1015.15f});
 
@@ -31,4 +34,17 @@ public class ElevationSumManagerTest {
         Assert.assertEquals(0f, elevationSumManager.getElevationGain_m(), 0.01);
         Assert.assertEquals(-48.0, elevationSumManager.getElevationLoss_m(), 0.01);
     }
+
+    @Test
+    public void sensorUnavailable() {
+        // given
+        elevationSumManager.setConnected(false);
+
+        // then
+        elevationSumManager.onSensorValueChanged(999f);
+
+        // then
+        Assert.assertNull(elevationSumManager.getElevationGain_m());
+        Assert.assertNull(elevationSumManager.getElevationLoss_m());
+    }
 }

src/main/java/de/dennisguse/opentracks/content/data/TrackPoint.java

@@ -32,7 +32,7 @@ public class TrackPoint {
     private Float heartRate_bpm = null;
     private Float cyclingCadence_rpm = null;
     private Float power = null;
-    private float elevationGain = Float.NaN;
+    private Float elevationGain = null;
 
     public TrackPoint() {
         this.location = new Location("");
@@ -94,14 +94,14 @@ public class TrackPoint {
     }
 
     public boolean hasElevationGain() {
-        return !Float.isNaN(elevationGain);
+        return elevationGain != null;
     }
 
     public float getElevationGain() {
         return elevationGain;
     }
 
-    public void setElevationGain(float elevationGain) {
+    public void setElevationGain(Float elevationGain) {
         this.elevationGain = elevationGain;
     }
 

src/main/java/de/dennisguse/opentracks/services/sensors/ElevationSumManager.java

@@ -7,6 +7,7 @@ import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 
 import de.dennisguse.opentracks.util.PressureSensorUtils;
@@ -37,9 +38,10 @@ public class ElevationSumManager implements SensorEventListener {
         if (pressureSensor == null) {
             Log.w(TAG, "No pressure sensor available.");
             isConnected = false;
+        } else {
+            isConnected = sensorManager.registerListener(this, pressureSensor, SAMPLING_RATE);
         }
 
-        isConnected = sensorManager.registerListener(this, pressureSensor, SAMPLING_RATE);
         lastAcceptedPressureValue_hPa = Float.NaN;
         reset();
     }
@@ -58,12 +60,19 @@ public class ElevationSumManager implements SensorEventListener {
         return isConnected;
     }
 
-    public float getElevationGain_m() {
-        return elevationGain_m;
+    @VisibleForTesting
+    public void setConnected(boolean isConnected) {
+        this.isConnected = isConnected;
     }
 
-    public float getElevationLoss_m() {
-        return elevationLoss_m;
+    public @Nullable
+    Float getElevationGain_m() {
+        return isConnected ? elevationGain_m : null;
+    }
+
+    public @Nullable
+    Float getElevationLoss_m() {
+        return isConnected ? elevationLoss_m : null;
     }
 
     public void reset() {
@@ -79,6 +88,10 @@ public class ElevationSumManager implements SensorEventListener {
 
     @Override
     public void onSensorChanged(SensorEvent event) {
+        if (!isConnected) {
+            Log.w(TAG, "Not connected to sensor, cannot process data.");
+            return;
+        }
         onSensorValueChanged(event.values[0]);
     }
 

src/main/res/values/settings.xml

@@ -5,7 +5,7 @@
     <bool name="stats_show_coordinate_default" translatable="false">false</bool>
 
     <string name="stats_show_grade_elevation_key" translatable="false">statsShowGradeElevation</string>
-    <bool name="stats_show_elevation_default" translatable="false">false</bool>
+    <bool name="stats_show_elevation_default" translatable="false">true</bool>
 
     <string name="stats_show_on_lockscreen_while_recording_key" translatable="false">trackdetail_show_on_lockscreen_while_recording</string>
     <bool name="stats_show_on_lockscreen_while_recording_default" translatable="false">false</bool>