Added elevation loss via barometer (like elevation gain). Fixes #547.

src/main/java/de/dennisguse/opentracks/io/file/exporter/KmlTrackWriter.java

@@ -51,6 +51,7 @@ public class KmlTrackWriter implements TrackWriter {
     public static final String EXTENDED_DATA_TYPE_HEART_RATE = "heart_rate";
     public static final String EXTENDED_DATA_TYPE_POWER = "power";
     public static final String EXTENDED_DATA_TYPE_ELEVATION_GAIN = "elevation_gain";
+    public static final String EXTENDED_DATA_TYPE_ELEVATION_LOSS = "elevation_loss";
 
     private static final String MARKER_ICON = "http://maps.google.com/mapfiles/kml/pushpin/blue-pushpin.png";
     private static final String START_ICON = "http://maps.google.com/mapfiles/kml/paddle/grn-circle.png";
@@ -70,6 +71,7 @@ public class KmlTrackWriter implements TrackWriter {
     private final List<Float> cadenceList = new ArrayList<>();
     private final List<Float> heartRateList = new ArrayList<>();
     private final List<Float> elevationGainList = new ArrayList<>();
+    private final List<Float> elevationLossList = new ArrayList<>();
 
     private TrackPoint startTrackPoint;
 
@@ -262,6 +264,9 @@ public class KmlTrackWriter implements TrackWriter {
                 if (elevationGainList.size() > 0) {
                     writeSimpleArrayData(elevationGainList, EXTENDED_DATA_TYPE_ELEVATION_GAIN);
                 }
+                if (elevationLossList.size() > 0) {
+                    writeSimpleArrayData(elevationLossList, EXTENDED_DATA_TYPE_ELEVATION_LOSS);
+                }
             }
             printWriter.println("</SchemaData>");
             printWriter.println("</ExtendedData>");
@@ -295,6 +300,9 @@ public class KmlTrackWriter implements TrackWriter {
                 if (trackPoint.hasElevationGain()) {
                     elevationGainList.add(trackPoint.getElevationGain());
                 }
+                if (trackPoint.hasElevationLoss()) {
+                    elevationLossList.add(trackPoint.getElevationLoss());
+                }
             }
         }
     }

src/main/java/de/dennisguse/opentracks/io/file/importer/KmlFileTrackImporter.java

@@ -69,6 +69,7 @@ public class KmlFileTrackImporter extends AbstractFileTrackImporter {
     private final ArrayList<Float> heartRateList = new ArrayList<>();
     private final ArrayList<Float> powerList = new ArrayList<>();
     private final ArrayList<Float> elevationGainList = new ArrayList<>();
+    private final ArrayList<Float> elevationLossList = new ArrayList<>();
 
     public KmlFileTrackImporter(Context context) {
         this(context, new ContentProviderUtils(context));
@@ -217,6 +218,7 @@ public class KmlFileTrackImporter extends AbstractFileTrackImporter {
         cadenceList.clear();
         powerList.clear();
         elevationGainList.clear();
+        elevationLossList.clear();
     }
 
     /**
@@ -242,6 +244,9 @@ public class KmlFileTrackImporter extends AbstractFileTrackImporter {
             if (i < elevationGainList.size()) {
                 trackPoint.setElevationGain(elevationGainList.get(i));
             }
+            if (i < elevationLossList.size()) {
+                trackPoint.setElevationLoss(elevationLossList.get(i));
+            }
 
             insertTrackPoint(trackPoint);
         }
@@ -311,6 +316,9 @@ public class KmlFileTrackImporter extends AbstractFileTrackImporter {
             case KmlTrackWriter.EXTENDED_DATA_TYPE_ELEVATION_GAIN:
                 elevationGainList.add(value);
                 break;
+            case KmlTrackWriter.EXTENDED_DATA_TYPE_ELEVATION_LOSS:
+                elevationLossList.add(value);
+                break;
             default:
                 Log.w(TAG, "Data from extended data " + extendedDataType + " is not (yet) supported.");
         }