Elevation now visible in statistics sheet - works for new tracks only (see #28)

app/src/main/java/org/y20k/trackbook/MainActivityTrackFragment.java

@@ -27,6 +27,7 @@ import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.constraint.ConstraintLayout;
+import android.support.constraint.Group;
 import android.support.design.widget.BottomSheetBehavior;
 import android.support.v4.app.DialogFragment;
 import android.support.v4.app.Fragment;
@@ -41,6 +42,7 @@ import android.widget.ImageButton;
 import android.widget.LinearLayout;
 import android.widget.Spinner;
 import android.widget.TextView;
+import android.widget.Toast;
 
 import org.osmdroid.api.IMapController;
 import org.osmdroid.tileprovider.tilesource.TileSourceFactory;
@@ -89,6 +91,11 @@ public class MainActivityTrackFragment extends Fragment implements AdapterView.O
     private TextView mDurationView;
     private TextView mRecordingStartView;
     private TextView mRecordingStopView;
+    private TextView mMaxAltitudeView;
+    private TextView mMinAltitudeView;
+    private TextView mPositiveElevationView;
+    private TextView mNegativeElevationView;
+    private Group mElevationDataViews;
     private BottomSheetBehavior mStatisticsSheetBehavior;
     private int mCurrentTrack;
     private Track mTrack;
@@ -204,6 +211,14 @@ public class MainActivityTrackFragment extends Fragment implements AdapterView.O
         mDurationView = (TextView) mRootView.findViewById(R.id.statistics_data_duration);
         mRecordingStartView = (TextView) mRootView.findViewById(R.id.statistics_data_recording_start);
         mRecordingStopView = (TextView) mRootView.findViewById(R.id.statistics_data_recording_stop);
+        mMaxAltitudeView = (TextView) mRootView.findViewById(R.id.statistics_data_max_altitude);
+        mMinAltitudeView = (TextView) mRootView.findViewById(R.id.statistics_data_min_altitude);
+        mPositiveElevationView = (TextView) mRootView.findViewById(R.id.statistics_data_positive_elevation);
+        mNegativeElevationView = (TextView) mRootView.findViewById(R.id.statistics_data_negative_elevation);
+        mElevationDataViews = (Group) mRootView.findViewById(R.id.elevation_data);
+
+        // attach listners for taps on elevation views
+        attachTapListeners();
 
         // display map and statistics
         if (savedInstanceState != null) {
@@ -359,9 +374,23 @@ public class MainActivityTrackFragment extends Fragment implements AdapterView.O
             mDurationView.setText(mTrack.getTrackDurationString());
             mRecordingStartView.setText(recordingStart);
             mRecordingStopView.setText(recordingStop);
+            mPositiveElevationView.setText(mTrack.getPositiveElevationString());
+            mNegativeElevationView.setText(mTrack.getNegativeElevationString());
+            mMaxAltitudeView.setText(mTrack.getMaxAltitudeString());
+            mMinAltitudeView.setText(mTrack.getMinAltitudeString());
+
+            // show/hide elevation views depending on file format version
+            if (mTrack.getTrackFormatVersion() > 1 || mTrack.getMinAltitude() > 0) {
+                // show elevation views
+                mElevationDataViews.setVisibility(View.VISIBLE);
+            } else {
+                // hide elevation views
+                mElevationDataViews.setVisibility(View.GONE);
+            }
 
             // draw track on map
             drawTrackOverlay(mTrack);
+
         } else {
             position = new GeoPoint(DEFAULT_LATITUDE, DEFAULT_LONGITUDE);
         }
@@ -531,6 +560,21 @@ public class MainActivityTrackFragment extends Fragment implements AdapterView.O
     }
 
 
+    /* Add tap listners to elevation data views */
+    private void attachTapListeners() {
+        int referencedIds[] = mElevationDataViews.getReferencedIds();
+        for (int id : referencedIds) {
+            mRootView.findViewById(id).setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View view) {
+                    // inform user about possible issues with altitude measurements
+                    Toast.makeText(mActivity, R.string.toast_message_elevation_info, Toast.LENGTH_LONG).show();
+                }
+            });
+        }
+    }
+
+
     /**
      * Inner class: Loads track from external storage using AsyncTask
      */
@@ -559,10 +603,6 @@ public class MainActivityTrackFragment extends Fragment implements AdapterView.O
         protected void onPostExecute(Void aVoid) {
             super.onPostExecute(aVoid);
 
-            // todo remove
-            StorageHelper storageHelper = new StorageHelper(mActivity);
-            storageHelper.calculateTrackElevation(mTrack);
-
             // display track on map
             displayTrack();
         }

app/src/main/java/org/y20k/trackbook/core/Track.java

@@ -49,6 +49,32 @@ public class Track implements TrackbookKeys, Parcelable {
     private float mStepCount;
     private final Date mRecordingStart;
     private Date mRecordingStop;
+    private double mMaxAltitude;
+    private double mMinAltitude;
+    private double mPositiveElevation;
+    private double mNegativeElevation;
+
+
+    /* Generic Constructor */
+    public Track(int trackFormatVersion, List<WayPoint> wayPoints, float trackLength, long duration, float stepCount, Date recordingStart, Date recordingStop, double maxAltitude, double minAltitude, double positiveElevation, double negativeElevation) {
+        mTrackFormatVersion = trackFormatVersion;
+        mWayPoints = wayPoints;
+        mTrackLength = trackLength;
+        mDuration = duration;
+        mStepCount = stepCount;
+        mRecordingStart = recordingStart;
+        mRecordingStop = recordingStop;
+        mMaxAltitude = maxAltitude;
+        mMinAltitude = minAltitude;
+        mPositiveElevation = positiveElevation;
+        mNegativeElevation = negativeElevation;
+    }
+
+
+    /* Copy Constructor */
+    public Track(Track track) {
+        this(track.getTrackFormatVersion(), track.getWayPoints(), track.getTrackLength(), track.getTrackDuration(), track.getStepCount(), track.getRecordingStart(), track.getRecordingStop(), track.getMaxAltitude(), track.getMinAltitude(), track.getPositiveElevation(), track.getNegativeElevation());
+    }
 
 
     /* Constructor */
@@ -60,6 +86,10 @@ public class Track implements TrackbookKeys, Parcelable {
         mStepCount = 0f;
         mRecordingStart = GregorianCalendar.getInstance().getTime();
         mRecordingStop = mRecordingStart;
+        mMaxAltitude = 0f;
+        mMinAltitude = 0f;
+        mPositiveElevation = 0f;
+        mNegativeElevation = 0f;
     }
 
 
@@ -72,6 +102,10 @@ public class Track implements TrackbookKeys, Parcelable {
         mStepCount = in.readFloat();
         mRecordingStart = new Date(in.readLong());
         mRecordingStop = new Date(in.readLong());
+        mMaxAltitude = in.readDouble();
+        mMinAltitude = in.readDouble();
+        mPositiveElevation = in.readDouble();
+        mNegativeElevation = in.readDouble();
     }
 
 
@@ -136,6 +170,36 @@ public class Track implements TrackbookKeys, Parcelable {
     }
 
 
+    /* Setter for maximum altitude of recording */
+    public void setMaxAltitude(double maxAltitude) {
+        mMaxAltitude = maxAltitude;
+    }
+
+
+    /* Setter for lowest altitude of recording */
+    public void setMinAltitude(double minAltitude) {
+        mMinAltitude = minAltitude;
+    }
+
+
+    /* Setter for positive elevation of recording (cumulative altitude difference) */
+    public void setPositiveElevation(double positiveElevation) {
+        mPositiveElevation = positiveElevation;
+    }
+
+
+    /* Setter for negative elevation of recording (cumulative altitude difference) */
+    public void setNegativeElevation(double megativeElevation) {
+        mNegativeElevation = megativeElevation;
+    }
+
+
+    /* Getter for file/track fornat version */
+    public int getTrackFormatVersion() {
+        return mTrackFormatVersion;
+    }
+
+
     /* Getter for mWayPoints */
     public List<WayPoint> getWayPoints() {
         return mWayPoints;
@@ -148,6 +212,12 @@ public class Track implements TrackbookKeys, Parcelable {
     }
 
 
+    /* Getter for track length */
+    public float getTrackLength() {
+        return mTrackLength;
+    }
+
+
     /* Getter for duration of track */
     public long getTrackDuration() {
         return mDuration;
@@ -171,26 +241,64 @@ public class Track implements TrackbookKeys, Parcelable {
     }
 
 
+    /* Getter for maximum altitude of recording */
+    public double getMaxAltitude() {
+        return mMaxAltitude;
+    }
+
+
+    /* Getter for lowest altitude of recording */
+    public double getMinAltitude() {
+        return mMinAltitude;
+    }
+
+
+    /* Getter for positive elevation of recording (cumulative altitude difference) */
+    public double getPositiveElevation() {
+        return mPositiveElevation;
+    }
+
+
+    /* Getter for negative elevation of recording (cumulative altitude difference) */
+    public double getNegativeElevation() {
+        return mNegativeElevation;
+    }
+
+
+    /* Getter for string representation of maximum altitude of recording */
+    public String getMaxAltitudeString() {
+        return convertDistanceToString(mMaxAltitude);
+    }
+
+
+    /* Getter for string representation of lowest altitude of recording */
+    public String getMinAltitudeString() {
+        return convertDistanceToString(mMinAltitude);
+    }
+
+
+    /* Getter for string representation of positive elevation of recording (cumulative altitude difference) */
+    public String getPositiveElevationString() {
+        return convertDistanceToString(mPositiveElevation);
+    }
+
+
+    /* Getter for string representation of negative elevation of recording (cumulative altitude difference) */
+    public String getNegativeElevationString() {
+        return convertDistanceToString(mNegativeElevation);
+    }
+
+
     /* Getter for string representation of track duration */
     public String getTrackDurationString() {
         return LocationHelper.convertToReadableTime(mDuration, true);
     }
 
+
     /* Getter for string representation of track distance */
     public String getTrackDistanceString() {
-        float trackDistance;
+        double trackDistance = (double) mWayPoints.get(mWayPoints.size()-1).getDistanceToStartingPoint();
-        String unit;
+        return convertDistanceToString(trackDistance);
-
-        if (getUnitSystem(Locale.getDefault()) == IMPERIAL) {
-            // get track distance and convert to feet
-            trackDistance = mWayPoints.get(mWayPoints.size()-1).getDistanceToStartingPoint() * 3.28084f;
-            unit = "ft";
-        } else {
-            // get track distance
-            trackDistance = mWayPoints.get(mWayPoints.size()-1).getDistanceToStartingPoint();
-            unit = "m";
-        }
-        return String.format (Locale.ENGLISH, "%.0f", trackDistance) + unit;
     }
 
 
@@ -216,6 +324,23 @@ public class Track implements TrackbookKeys, Parcelable {
     }
 
 
+    /* Converts a given distance value to a readable string */
+    private String convertDistanceToString(double distance) {
+        // check for locale and set unit system accordingly
+        String unit;
+        if (getUnitSystem(Locale.getDefault()) == IMPERIAL) {
+            // convert distance to feet
+            distance = distance * 3.28084f;
+            // set measurement unit
+            unit = "ft";
+        } else {
+            // set measurement unit
+            unit = "m";
+        }
+        return String.format (Locale.ENGLISH, "%.0f", distance) + unit;
+    }
+
+
     /* Determines which unit system the device is using (metric or imperial) */
     private int getUnitSystem(Locale locale) {
         // America (US), Liberia (LR), Myanmar(MM) use the imperial system
@@ -245,8 +370,11 @@ public class Track implements TrackbookKeys, Parcelable {
         parcel.writeFloat(mStepCount);
         parcel.writeLong(mRecordingStart.getTime());
         parcel.writeLong(mRecordingStop.getTime());
+        parcel.writeDouble(mMaxAltitude);
+        parcel.writeDouble(mMinAltitude);
+        parcel.writeDouble(mPositiveElevation);
+        parcel.writeDouble(mNegativeElevation);
     }
 
 
-
 }

app/src/main/java/org/y20k/trackbook/core/TrackBuilder.java

@@ -0,0 +1,80 @@
+/**
+ * TrackBuilder.java
+ * Implements a builder for the Track class
+ * A TrackBuilder can build a track object depending on the version of its file format
+ *
+ * This file is part of
+ * TRACKBOOK - Movement Recorder for Android
+ *
+ * Copyright (c) 2016-18 - Y20K.org
+ * Licensed under the MIT-License
+ * http://opensource.org/licenses/MIT
+ *
+ * Trackbook uses osmdroid - OpenStreetMap-Tools for Android
+ * https://github.com/osmdroid/osmdroid
+ */
+
+
+package org.y20k.trackbook.core;
+
+import org.y20k.trackbook.helpers.LogHelper;
+
+import java.util.Date;
+import java.util.List;
+
+
+/**
+ * TrackBuilder class
+ */
+public class TrackBuilder {
+
+    /* Define log tag */
+    private static final String LOG_TAG = TrackBuilder.class.getSimpleName();
+
+
+    /* Main class variables */
+    private final int mTrackFormatVersion;
+    private final List<WayPoint> mWayPoints;
+    private float mTrackLength;
+    private long mDuration;
+    private float mStepCount;
+    private final Date mRecordingStart;
+    private Date mRecordingStop;
+    private double mMaxAltitude;
+    private double mMinAltitude;
+    private double mPositiveElevation;
+    private double mNegativeElevation;
+
+
+    /* Generic Constructor */
+    public TrackBuilder(int trackFormatVersion, List<WayPoint> wayPoints, float trackLength, long duration, float stepCount, Date recordingStart, Date recordingStop, double maxAltitude, double minAltitude, double positiveElevation, double negativeElevation) {
+        mTrackFormatVersion = trackFormatVersion;
+        mWayPoints = wayPoints;
+        mTrackLength = trackLength;
+        mDuration = duration;
+        mStepCount = stepCount;
+        mRecordingStart = recordingStart;
+        mRecordingStop = recordingStop;
+        mMaxAltitude = maxAltitude;
+        mMinAltitude = minAltitude;
+        mPositiveElevation = positiveElevation;
+        mNegativeElevation = negativeElevation;
+    }
+
+
+    /* Builds and return a Track object */
+    public Track toTrack() {
+        switch (mTrackFormatVersion) {
+            case 1:
+                // file format version 1 - does not have elevation data stored
+                return new Track(mTrackFormatVersion, mWayPoints, mTrackLength, mDuration, mStepCount, mRecordingStart, mRecordingStop, 0f, 0f, 0f, 0f);
+            case 2:
+                // file format version 2 (current version)
+                return new Track(mTrackFormatVersion, mWayPoints, mTrackLength, mDuration, mStepCount, mRecordingStart, mRecordingStop, mMaxAltitude, mMinAltitude, mPositiveElevation, mNegativeElevation);
+            default:
+                LogHelper.e(LOG_TAG, "Unknown file format version: " + mTrackFormatVersion);
+                return null;
+        }
+    }
+
+}

app/src/main/java/org/y20k/trackbook/helpers/StorageHelper.java

@@ -17,7 +17,6 @@
 package org.y20k.trackbook.helpers;
 
 import android.content.Context;
-import android.location.Location;
 import android.os.Environment;
 import android.support.annotation.Nullable;
 import android.support.v4.os.EnvironmentCompat;
@@ -28,6 +27,7 @@ import com.google.gson.GsonBuilder;
 
 import org.y20k.trackbook.R;
 import org.y20k.trackbook.core.Track;
+import org.y20k.trackbook.core.TrackBuilder;
 
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
@@ -101,6 +101,9 @@ public class StorageHelper implements TrackbookKeys {
         }
 
         if (mFolder != null && mFolder.exists() && mFolder.isDirectory() && mFolder.canWrite() && recordingStart != null && track != null) {
+            // calculate elevation and store it in track
+            track = calculateElevation(track);
+
             // create file object
             String fileName;
             if (fileType == FILE_TEMP_TRACK) {
@@ -221,22 +224,19 @@ public class StorageHelper implements TrackbookKeys {
         try (BufferedReader br = new BufferedReader(new FileReader(file))) {
             LogHelper.v(LOG_TAG, "Loading track from external storage: " + file.toString());
 
+            // read until last line reached
             String line;
             StringBuilder sb = new StringBuilder("");
-
-            // read until last line reached
             while ((line = br.readLine()) != null) {
                 sb.append(line);
                 sb.append("\n");
             }
 
-            // TODO implement a format version check before handing the file to GSON
+            // prepare GsonBuilder and return Track object
-
-            // get track from JSON
             GsonBuilder gsonBuilder = new GsonBuilder();
             gsonBuilder.setDateFormat("M/d/yy hh:mm a");
             Gson gson = gsonBuilder.create();
-            return gson.fromJson(sb.toString(), Track.class);
+            return gson.fromJson(sb.toString(), TrackBuilder.class).toTrack();
 
         } catch (IOException e) {
             LogHelper.e(LOG_TAG, "Unable to read file from external storage: " + file.toString());
@@ -360,38 +360,105 @@ public class StorageHelper implements TrackbookKeys {
     }
 
 
-    /* Calculates positive and negative elevation of track */ // todo make private
+    /* Calculates positive and negative elevation of track */
-    public Track calculateTrackElevation(@Nullable Track track) {
+    private Track calculateElevation(@Nullable Track track) {
+        double maxAltitude = 0;
+        double minAltitude = 0;
         double positiveElevation = 0;
         double negativeElevation = 0;
-        double LIKELY_MEASUREMENT_ERROR = 25; // move to TrackbookKeys
 
         if (track != null && track.getWayPoints().size() > 0 && track.getWayPointLocation(0).getAltitude() != 0) {
-            Location previousLocation;
+            double previousLocationHeight;
-            Location nextLocation;
+            double currentLocationHeight;
+            long previousTimeStamp;
+            long currentTimeStamp;
+
+            // initial values for max height and min height - first waypoint
+            maxAltitude = track.getWayPointLocation(0).getAltitude();
+            minAltitude = maxAltitude;
+
+            // apply filter & smooth data
+//            track = lowPass(track, 15f, 35f);
 
             // iterate over track
-            for (int i = 0; i < track.getWayPoints().size() - 1; i++ ) {
+            for (int i = 1; i < track.getWayPoints().size(); i++ ) {
-                // calculate elevation difference
-                previousLocation = track.getWayPointLocation(i);
-                nextLocation = track.getWayPointLocation(i + 1);
-                double difference = nextLocation.getAltitude() - previousLocation.getAltitude();
-                LogHelper.i(LOG_TAG, "next:" + nextLocation.getAltitude() + " | prev:" + previousLocation.getAltitude() + " | diff:" + difference); // todo remove
 
-                // add difference to elevation
+                // get time difference
-                if (difference > 0 && difference < LIKELY_MEASUREMENT_ERROR) {
+                previousTimeStamp = track.getWayPointLocation(i -1).getTime();
-                    positiveElevation = positiveElevation + difference;
+                currentTimeStamp = track.getWayPointLocation(i).getTime();
-                } else if (difference < 0 && difference > -LIKELY_MEASUREMENT_ERROR) {
+                double timeDiff = (currentTimeStamp - previousTimeStamp);
-                    negativeElevation = negativeElevation + difference;
+
+                // factor is bigger than 1 if the time stamp difference is larger than the movement recording interval (usually 15 seconds)
+                double timeDiffFactor = timeDiff / FIFTEEN_SECONDS_IN_MILLISECONDS;
+
+                // height of previous and current waypoints
+                previousLocationHeight = track.getWayPointLocation(i -1).getAltitude();
+                currentLocationHeight = track.getWayPointLocation(i).getAltitude();
+
+                // check for new min and max heights
+                if (currentLocationHeight > maxAltitude) {
+                    maxAltitude = currentLocationHeight;
+                } else if (minAltitude == 0 || currentLocationHeight < minAltitude) {
+                    minAltitude = currentLocationHeight;
+                }
+
+                // get elevation difference and sum it up
+                double altitudeDiff = currentLocationHeight - previousLocationHeight;
+                if (altitudeDiff > 0 && altitudeDiff < MEASUREMENT_ERROR_THRESHOLD * timeDiffFactor && currentLocationHeight != 0) {
+                    positiveElevation = positiveElevation + altitudeDiff;
+                } else if (altitudeDiff < 0 && altitudeDiff > -MEASUREMENT_ERROR_THRESHOLD * timeDiffFactor && currentLocationHeight != 0) {
+                    negativeElevation = negativeElevation + altitudeDiff;
                 }
             }
 
-            String toastString = "Calculated elevation: +" +  positiveElevation + " / " + negativeElevation + " meters"; // todo remove
+            // store elevation data in track
-            Toast.makeText(mContext, toastString, Toast.LENGTH_LONG).show(); // todo remove
+            track.setMaxAltitude(maxAltitude);
-            LogHelper.i(LOG_TAG, toastString); // todo remove
+            track.setMinAltitude(minAltitude);
+            track.setPositiveElevation(positiveElevation);
+            track.setNegativeElevation(negativeElevation);
         }
         return track;
     }
 
+    /* Tries to smooth the elevation data using a low pass filter */
+    private Track lowPass(Track input, float dt, float rc) {
+        /* The following code is adapted from https://en.wikipedia.org/wiki/Low-pass_filter
+          *
+          * // Return RC low-pass filter output samples, given input samples,
+          * // time interval dt, and time constant RC
+          * function lowpass(real[0..n] x, real dt, real RC)
+          *     var real[0..n] y
+          *     var real α := dt / (RC + dt)
+          *     y[0] := α * x[0]
+          *     for i from 1 to n
+          *         y[i] := α * x[i] + (1-α) * y[i-1]
+          *     return y
+          */
+
+        // copy input track
+        Track output = new Track(input);
+
+        // calculate alpha
+        float alpha = dt / (rc + dt);
+
+        // set initial value for first waypoint
+        double outputInitialAltituteValue = alpha * input.getWayPoints().get(0).getLocation().getAltitude();
+        output.getWayPoints().get(0).getLocation().setAltitude(outputInitialAltituteValue);
+
+        double inputCurrentAltitudeValue;
+        double outputPreviousAltitudeValue;
+        double outputCurrentAltitudeValue;
+        for (int i = 1; i < input.getSize(); i++) {
+            inputCurrentAltitudeValue = input.getWayPoints().get(i).getLocation().getAltitude();
+            outputPreviousAltitudeValue = output.getWayPoints().get(i-1).getLocation().getAltitude();
+
+            outputCurrentAltitudeValue = alpha * inputCurrentAltitudeValue + (1 - alpha) * outputPreviousAltitudeValue;
+
+            output.getWayPoints().get(i).getLocation().setAltitude(outputCurrentAltitudeValue);
+        }
+
+        return output;
+    }
+
 
 }

app/src/main/java/org/y20k/trackbook/helpers/TrackbookKeys.java

@@ -111,10 +111,10 @@ public interface TrackbookKeys {
     String NOTIFICATION_CHANEL_ID_RECORDING_CHANNEL ="notificationChannelIdRecordingChannel";
 
     /* MISC */
+    int CURRENT_TRACK_FORMAT_VERSION = 2; // incremental version number to prevent issues in case the Track format evolves
     double DEFAULT_LATITUDE = 49.41667; // latitude Nordkapp, Norway
     double DEFAULT_LONGITUDE = 8.67201; // longitude Nordkapp, Norway
-    int CURRENT_TRACK_FORMAT_VERSION = 1; // incremental version number to prevent issues in case the Track format evolves
+    int MEASUREMENT_ERROR_THRESHOLD = 10; // altitude changes of 10 meter or more (per 15 seconds) are being discarded
     int REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS = 124;
-    int INFOSHEET_CONTENT_ABOUT = 1;
 
 }

app/src/main/res/layout/fragment_main_track_statistics.xml

@@ -5,6 +5,12 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content">
 
+    <android.support.constraint.Group
+        android:id="@+id/elevation_data"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        app:constraint_referenced_ids="statistics_p_positive_elevation, statistics_data_positive_elevation, statistics_p_negative_elevation, statistics_data_negative_elevation, statistics_p_max_altitude, statistics_data_max_altitude, statistics_p_min_altitude, statistics_data_min_altitude" />
+
     <TextView
         android:id="@+id/statistics_headline"
         android:layout_width="0dp"
@@ -148,11 +154,9 @@
         android:id="@+id/statistics_p_recording_stop"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginBottom="16dp"
         android:layout_marginTop="16dp"
         android:contentDescription="@string/descr_statistics_sheet_p_recording_end"
         android:text="@string/statistics_sheet_p_recording_stop"
-        app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintStart_toStartOf="@+id/statistics_p_recording_start"
         app:layout_constraintTop_toBottomOf="@+id/statistics_p_recording_start" />
 
@@ -168,4 +172,90 @@
         app:layout_constraintStart_toEndOf="@+id/statistics_p_recording_stop"
         app:layout_constraintTop_toTopOf="@+id/statistics_p_recording_stop" />
 
+    <TextView
+        android:id="@+id/statistics_p_positive_elevation"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:contentDescription="@string/descr_statistics_sheet_p_positive_elevation"
+        android:text="@string/statistics_sheet_p_positive_elevation"
+        app:layout_constraintStart_toStartOf="@+id/statistics_p_recording_stop"
+        app:layout_constraintTop_toBottomOf="@+id/statistics_p_recording_stop" />
+
+    <TextView
+        android:id="@+id/statistics_data_positive_elevation"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:text="@string/statistics_sheet_p_default_data"
+        android:textAppearance="@android:style/TextAppearance.Material.Medium"
+        app:layout_constraintBottom_toBottomOf="@+id/statistics_p_positive_elevation"
+        app:layout_constraintStart_toEndOf="@+id/statistics_p_positive_elevation"
+        app:layout_constraintTop_toTopOf="@+id/statistics_p_positive_elevation" />
+
+    <TextView
+        android:id="@+id/statistics_p_negative_elevation"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:contentDescription="@string/descr_statistics_sheet_p_negative_elevation"
+        android:text="@string/statistics_sheet_p_negative_elevation"
+        app:layout_constraintStart_toStartOf="@+id/statistics_p_positive_elevation"
+        app:layout_constraintTop_toBottomOf="@+id/statistics_p_positive_elevation" />
+
+    <TextView
+        android:id="@+id/statistics_data_negative_elevation"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:text="@string/statistics_sheet_p_default_data"
+        android:textAppearance="@android:style/TextAppearance.Material.Medium"
+        app:layout_constraintBottom_toBottomOf="@+id/statistics_p_negative_elevation"
+        app:layout_constraintStart_toEndOf="@+id/statistics_p_negative_elevation"
+        app:layout_constraintTop_toTopOf="@+id/statistics_p_negative_elevation" />
+
+    <TextView
+        android:id="@+id/statistics_p_max_altitude"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:contentDescription="@string/descr_statistics_sheet_p_max_altitude"
+        android:text="@string/statistics_sheet_p_max_altitude"
+        app:layout_constraintStart_toStartOf="@+id/statistics_p_negative_elevation"
+        app:layout_constraintTop_toBottomOf="@+id/statistics_p_negative_elevation" />
+
+    <TextView
+        android:id="@+id/statistics_data_max_altitude"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:text="@string/statistics_sheet_p_default_data"
+        android:textAppearance="@android:style/TextAppearance.Material.Medium"
+        app:layout_constraintBottom_toBottomOf="@+id/statistics_p_max_altitude"
+        app:layout_constraintStart_toEndOf="@+id/statistics_p_max_altitude"
+        app:layout_constraintTop_toTopOf="@+id/statistics_p_max_altitude" />
+
+    <TextView
+        android:id="@+id/statistics_p_min_altitude"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginBottom="16dp"
+        android:layout_marginTop="16dp"
+        android:contentDescription="@string/descr_statistics_sheet_p_min_altitude"
+        android:text="@string/statistics_sheet_p_min_altitude"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintStart_toStartOf="@+id/statistics_p_max_altitude"
+        app:layout_constraintTop_toBottomOf="@+id/statistics_p_max_altitude" />
+
+    <TextView
+        android:id="@+id/statistics_data_min_altitude"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:text="@string/statistics_sheet_p_default_data"
+        android:textAppearance="@android:style/TextAppearance.Material.Medium"
+        app:layout_constraintBottom_toBottomOf="@+id/statistics_p_min_altitude"
+        app:layout_constraintStart_toEndOf="@+id/statistics_p_min_altitude"
+        app:layout_constraintTop_toTopOf="@+id/statistics_p_min_altitude" />
+
 </android.support.constraint.ConstraintLayout>

app/src/main/res/values-de/strings.xml

@@ -56,8 +56,9 @@
     <string name="toast_message_save_track">Aufzeichnung wird gespeichert.</string>
     <string name="toast_message_last_location_age_one_hour">über eine Stunde</string>
     <string name="toast_message_track_clear">Aufzeichnung zurückgesetzt.</string>
-    <string name="toast_message_export_success">GPX export successful:</string>
+    <string name="toast_message_export_success">GPX-Export erfolgreich:</string>
-    <string name="toast_message_export_fail">GPX export failed:</string>
+    <string name="toast_message_export_fail">GPX-Export fehlgeschlagen:</string>
+    <string name="toast_message_elevation_info">Hinweis: Die Genauogkeit der Höhenmeter-Werte ist geräteabhängig. Gemessen werden die Steigungen und Gefälle der Gesamtstrecke.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Quelle</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Dauer (gesamt):</string>
     <string name="statistics_sheet_p_recording_start">Start der Aufzeichnung:</string>
     <string name="statistics_sheet_p_recording_stop">Ende der Aufzeichnung:</string>
+    <string name="statistics_sheet_p_max_altitude">Höchster Wegpunkt:</string>
+    <string name="statistics_sheet_p_min_altitude">Tiefster Wegpunkt:</string>
+    <string name="statistics_sheet_p_positive_elevation">Höhenmeter (bergauf):</string>
+    <string name="statistics_sheet_p_negative_elevation">Höhenmeter (bergab):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Hallo</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">Wert: Dauer</string>
     <string name="descr_statistics_sheet_p_recording_start_value">Wert: Start der Aufzeichnung</string>
     <string name="descr_statistics_sheet_p_recording_end_value">Wert: Ende der Aufzeichnung</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Wert: Höchster Wegpunkt</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Wert: Tiefster Wegpunkt:</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Wert: Höhenmeter (bergauf)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Wert Höhenmeter (bergab)</string>
     <string name="descr_track_selector">Auswahl-Menü für weitere Aufzeichnungen</string>
     <string name="descr_export_button">Button Track Exportierem</string>
     <string name="descr_delete_button">Button Track Löschen</string>

app/src/main/res/values-id/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">Current track data removed.</string>
     <string name="toast_message_export_success">GPX export successful:</string>
     <string name="toast_message_export_fail">GPX export failed:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Source</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Total duration:</string>
     <string name="statistics_sheet_p_recording_start">Recording started:</string>
     <string name="statistics_sheet_p_recording_stop">Recording stopped:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Hello</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">Value: Duration</string>
     <string name="descr_statistics_sheet_p_recording_start_value">Value: Start of recording</string>
     <string name="descr_statistics_sheet_p_recording_end_value">Value: End of recording</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Value: Highest waypoint</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Value: Lowest waypoint</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Value: Elevation (uphill)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Value: Elevation (downhill)</string>
     <string name="descr_track_selector">Dropdown menu for further tracks</string>
     <string name="descr_export_button">Track export button</string>
     <string name="descr_delete_button">Track delete button</string>

app/src/main/res/values-it/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">Dati della traccia corrente rimossi.</string>
     <string name="toast_message_export_success">L\'esportazione GPX è riuscita:</string>
     <string name="toast_message_export_fail">L\'esportazione GPX non è riuscita:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Fonte</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Durata totale:</string>
     <string name="statistics_sheet_p_recording_start">Registrazione avviata il:</string>
     <string name="statistics_sheet_p_recording_stop">Registrazione interrotta il:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Ciao</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">Valore: Durata</string>
     <string name="descr_statistics_sheet_p_recording_start_value">Valore: Inizio della registrazione</string>
     <string name="descr_statistics_sheet_p_recording_end_value">Valore: Fine della registrazione</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Value: Highest waypoint</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Value: Lowest waypoint</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Value: Elevation (uphill)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Value: Elevation (downhill)</string>
     <string name="descr_track_selector">Elenco registrazioni</string>
     <string name="descr_export_button">Pulsante di esportazione della traccia</string>
     <string name="descr_delete_button">Pulsante di eliminazione della traccia</string>

app/src/main/res/values-ja/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">現在のトレース データを削除しました。</string>
     <string name="toast_message_export_success">GPX export successful:</string>
     <string name="toast_message_export_fail">GPX export failed:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">ソース</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">合計時間:</string>
     <string name="statistics_sheet_p_recording_start">記録の開始:</string>
     <string name="statistics_sheet_p_recording_stop">記録の停止:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">こんにちは</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">値: 期間</string>
     <string name="descr_statistics_sheet_p_recording_start_value">値: 記録の開始</string>
     <string name="descr_statistics_sheet_p_recording_end_value">値: 記録の終了</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Value: Highest waypoint</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Value: Lowest waypoint</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Value: Elevation (uphill)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Value: Elevation (downhill)</string>
     <string name="descr_track_selector">ドロップダウン メニューでさらにトレース</string>
     <string name="descr_export_button">Track export button</string>
     <string name="descr_delete_button">トレース削除ボタン</string>

app/src/main/res/values-nb-rNO/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">Nåværende turdata fjernet.</string>
     <string name="toast_message_export_success">GPX-eksportering vellykket:</string>
     <string name="toast_message_export_fail">GPX-eksportering mislyktes:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Kilde</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Total varighet:</string>
     <string name="statistics_sheet_p_recording_start">Opptak startet:</string>
     <string name="statistics_sheet_p_recording_stop">Opptak stoppet:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Hallo</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">Verdi: Varighet</string>
     <string name="descr_statistics_sheet_p_recording_start_value">Verdi: Opptaksstart</string>
     <string name="descr_statistics_sheet_p_recording_end_value">Verdi: Opptaksslutt</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Value: Highest waypoint</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Value: Lowest waypoint</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Value: Elevation (uphill)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Value: Elevation (downhill)</string>
     <string name="descr_track_selector">Nedtrekksmeny for ytterligere turer</string>
     <string name="descr_export_button">Tureksportknapp</string>
     <string name="descr_delete_button">Turslettingsknapp</string>

app/src/main/res/values-nl/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">Huidige baangegevens verwijderd.</string>
     <string name="toast_message_export_success">GPX export successful:</string>
     <string name="toast_message_export_fail">GPX export failed:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Bron</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Totale duur:</string>
     <string name="statistics_sheet_p_recording_start">Bijhouden gestart:</string>
     <string name="statistics_sheet_p_recording_stop">Bijhouden gestopt:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Hallo</string>

app/src/main/res/values/strings.xml

@@ -58,6 +58,7 @@
     <string name="toast_message_track_clear">Current track data removed.</string>
     <string name="toast_message_export_success">GPX export successful:</string>
     <string name="toast_message_export_fail">GPX export failed:</string>
+    <string name="toast_message_elevation_info">Hint: The accuracy of elevation data depends on your device. The uphill and downhill elevation of the whole route is measured.</string>
 
     <!-- map markers -->
     <string name="marker_description_source">Source</string>
@@ -74,6 +75,10 @@
     <string name="statistics_sheet_p_duration">Total duration:</string>
     <string name="statistics_sheet_p_recording_start">Recording started:</string>
     <string name="statistics_sheet_p_recording_stop">Recording stopped:</string>
+    <string name="statistics_sheet_p_max_altitude">Highest waypoint:</string>
+    <string name="statistics_sheet_p_min_altitude">Lowest waypoint:</string>
+    <string name="statistics_sheet_p_positive_elevation">Elevation (uphill):</string>
+    <string name="statistics_sheet_p_negative_elevation">Elevation (downhill):</string>
 
     <!-- onboarding layout -->
     <string name="layout_onboarding_h1_welcome">Hello</string>
@@ -114,6 +119,10 @@
     <string name="descr_statistics_sheet_p_duration_value">Value: Duration</string>
     <string name="descr_statistics_sheet_p_recording_start_value">Value: Start of recording</string>
     <string name="descr_statistics_sheet_p_recording_end_value">Value: End of recording</string>
+    <string name="descr_statistics_sheet_p_max_altitude">Value: Highest waypoint</string>
+    <string name="descr_statistics_sheet_p_min_altitude">Value: Lowest waypoint</string>
+    <string name="descr_statistics_sheet_p_positive_elevation">Value: Elevation (uphill)</string>
+    <string name="descr_statistics_sheet_p_negative_elevation">Value: Elevation (downhill)</string>
     <string name="descr_track_selector">Dropdown menu for further tracks</string>
     <string name="descr_export_button">Track export button</string>
     <string name="descr_delete_button">Track delete button</string>