Release v3.2.7

Also removed configuration option.

.idea/render.experimental.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RenderSettings">
+    <option name="showDecorations" value="true" />
+  </component>
+</project>

fastlane/metadata/android/de-DE/full_description.txt

@@ -1,4 +1,4 @@
-Open Tracks – ein GPS-Tracker, der deine Daten für sich behält.
+OpenTracks – ein GPS-Tracker, der deine Daten für sich behält.
 Erfasst deine Kilometer, ohne dass es jemand anderes tut.
 
 Funktionen & Features:

fastlane/metadata/android/de-DE/short_description.txt

@@ -1 +1 @@
-Open Tracks – ein GPS-Tracker, der deine Daten für sich behält.
+OpenTracks – ein GPS-Tracker, der deine Daten für sich behält.

fastlane/metadata/android/en-US/changelogs/3149.txt

@@ -0,0 +1,10 @@
+v3.2.7: OpenTracks
+
+Changes:
+- Notification show GPS accuracy
+- Show heads-up notification if GPS accuracy drops beyond threshold
+- Always show chart by time as well as by distance
+- Added help (in Settings)
+
+Bugfix:
+- TrackDetailActivity: disabled non-working landscape mode (temporary)

fastlane/metadata/android/es-ES/full_description.txt

@@ -0,0 +1,8 @@
+OpenTracks es un tracker deportivo que respeta tu privacidad.
+
+Funciones:
+* Tracker deportivo: haz un seguimiento de tus actividades al aire libre
+* Marca lugares de interés, incluso agrega fotos a los marcadores
+* Pulsómetro (compatible con dispositivos Bluetooth LE)
+* Exporta tus rutas como KML o GPX
+* Completamente offline, no necesitas internet

fastlane/metadata/android/es-ES/short_description.txt

@@ -0,0 +1 @@
+OpenTracks es un tracker deportivo que respeta tu privacidad.

fastlane/metadata/android/es-ES/title.txt

@@ -0,0 +1 @@
+OpenTracks

src/androidTest/java/de/dennisguse/opentracks/fragments/ChartFragmentTest.java

@@ -46,8 +46,10 @@ public class ChartFragmentTest {
 
     @Before
     public void setUp() {
-        chartFragment = new ChartFragment();
-        chartFragment.setChartView(new ChartView(ApplicationProvider.getApplicationContext()));
+        boolean chartByDistance = false;
+        chartFragment = new ChartFragment(chartByDistance) {
+        };
+        chartFragment.setChartView(new ChartView(ApplicationProvider.getApplicationContext(), chartByDistance));
         chartFragment.setTripStatisticsUpdater(TrackStubUtils.INITIAL_TIME);
     }
 

src/androidTest/java/de/dennisguse/opentracks/services/TrackRecordingServiceNotificationManagerTest.java

@@ -0,0 +1,54 @@
+package de.dennisguse.opentracks.services;
+
+import android.app.NotificationManager;
+import android.content.Context;
+import android.location.Location;
+
+import androidx.core.app.NotificationCompat;
+import androidx.test.core.app.ApplicationProvider;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@RunWith(MockitoJUnitRunner.class)
+public class TrackRecordingServiceNotificationManagerTest {
+
+    private Context context = ApplicationProvider.getApplicationContext();
+
+    @Mock
+    private Location locationMock;
+
+    @Mock
+    private NotificationCompat.Builder notificationCompatBuilder;
+
+    @Mock
+    private NotificationManager notificationManager;
+
+    @Test
+    public void updateLocation_triggersAlertOnlyOnFirstInaccurateLocation() {
+        when(locationMock.hasAccuracy()).thenReturn(true);
+        when(locationMock.getAccuracy()).thenReturn(999f);
+        when(notificationCompatBuilder.setContentText(anyString())).thenReturn(notificationCompatBuilder);
+        when(notificationCompatBuilder.setOnlyAlertOnce(anyBoolean())).thenReturn(notificationCompatBuilder);
+
+        TrackRecordingServiceNotificationManager subject = new TrackRecordingServiceNotificationManager(notificationManager, notificationCompatBuilder);
+
+        // when
+        subject.updateLocation(context, locationMock, 100);
+        subject.updateLocation(context, locationMock, 100);
+        subject.updateLocation(context, locationMock, 1000);
+        subject.updateLocation(context, locationMock, 100);
+
+        // then
+        verify(notificationCompatBuilder, times(6)).setOnlyAlertOnce(true);
+        verify(notificationCompatBuilder, times(2)).setOnlyAlertOnce(false);
+    }
+}

src/main/AndroidManifest.xml

@@ -16,8 +16,8 @@ limitations under the License.
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="de.dennisguse.opentracks"
     android:installLocation="auto"
-    android:versionCode="3137"
-    android:versionName="v3.2.6"> <!-- For FDroid. -->
+    android:versionCode="3149"
+    android:versionName="v3.2.7"> <!-- For FDroid. -->
     <!-- Permission to initialize services -->
     <application
         android:name=".Startup"
@@ -32,6 +32,10 @@ limitations under the License.
 
         <activity android:name=".DeleteActivity" />
 
+        <activity
+            android:name=".HelpActivity"
+            android:label="@string/menu_help" />
+
         <activity
             android:name=".io.file.importer.ImportActivity"
             android:theme="@style/ThemeCustomTransparent">
@@ -50,10 +54,10 @@ limitations under the License.
             </intent-filter>
         </activity>
 
-        <activity android:name=".MarkerEditActivity" />
-
         <activity android:name=".MarkerDetailActivity" />
 
+        <activity android:name=".MarkerEditActivity" />
+
         <activity
             android:name=".MarkerListActivity"
             android:label="@string/menu_markers">
@@ -79,7 +83,9 @@ limitations under the License.
 
         <activity android:name=".TrackEditActivity" />
 
-        <activity android:name=".TrackListActivity">
+        <activity
+            android:name=".TrackListActivity"
+            android:screenOrientation="userPortrait">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />

src/main/java/de/dennisguse/opentracks/AbstractActivity.java

@@ -17,11 +17,12 @@
 package de.dennisguse.opentracks;
 
 import android.os.Bundle;
-import android.speech.tts.TextToSpeech;
 
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
 
+import de.dennisguse.opentracks.util.TTSUtils;
+
 /**
  * @author Jimmy Shih
  */
@@ -32,7 +33,7 @@ public abstract class AbstractActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
 
         // Set volume control stream for text to speech
-        setVolumeControlStream(TextToSpeech.Engine.DEFAULT_STREAM);
+        setVolumeControlStream(TTSUtils.getTTSStream());
 
         setContentView(getLayoutResId());
 

src/main/java/de/dennisguse/opentracks/ChartView.java

@@ -107,7 +107,7 @@ public class ChartView extends View {
     private int effectiveWidth = 0;
     private int effectiveHeight = 0;
 
-    private boolean chartByDistance = true;
+    private boolean chartByDistance;
     private boolean metricUnits = true;
     private boolean reportSpeed = true;
     private boolean showPointer = false;
@@ -117,8 +117,9 @@ public class ChartView extends View {
      *
      * @param context the context
      */
-    public ChartView(Context context) {
+    public ChartView(Context context, boolean chartByDistance) {
         super(context);
+        this.chartByDistance = chartByDistance;
 
         series[ELEVATION_SERIES] = new ChartValueSeries(context,
                 Integer.MIN_VALUE,

src/main/java/de/dennisguse/opentracks/HelpActivity.java

@@ -0,0 +1,9 @@
+package de.dennisguse.opentracks;
+
+public class HelpActivity extends AbstractActivity {
+
+    @Override
+    protected int getLayoutResId() {
+        return R.layout.help;
+    }
+}

src/main/java/de/dennisguse/opentracks/TrackDetailActivity.java

@@ -45,7 +45,8 @@ import de.dennisguse.opentracks.content.TrackDataHub;
 import de.dennisguse.opentracks.content.Waypoint;
 import de.dennisguse.opentracks.content.Waypoint.WaypointType;
 import de.dennisguse.opentracks.content.WaypointCreationRequest;
-import de.dennisguse.opentracks.fragments.ChartFragment;
+import de.dennisguse.opentracks.fragments.ChartDistanceFragment;
+import de.dennisguse.opentracks.fragments.ChartTimeFragment;
 import de.dennisguse.opentracks.fragments.ChooseActivityTypeDialogFragment;
 import de.dennisguse.opentracks.fragments.ConfirmDeleteDialogFragment;
 import de.dennisguse.opentracks.fragments.StatsFragment;
@@ -205,8 +206,11 @@ public class TrackDetailActivity extends AbstractListActivity implements ChooseA
         TabSpec statsTabSpec = tabHost.newTabSpec(StatsFragment.STATS_FRAGMENT_TAG).setIndicator(getString(R.string.track_detail_stats_tab));
         tabsAdapter.addTab(statsTabSpec, StatsFragment.class, null);
 
-        TabSpec chartTabSpec = tabHost.newTabSpec(ChartFragment.CHART_FRAGMENT_TAG).setIndicator(getString(R.string.track_detail_chart_tab));
-        tabsAdapter.addTab(chartTabSpec, ChartFragment.class, null);
+        TabSpec chartTimeTabSpec = tabHost.newTabSpec(ChartTimeFragment.CHART_FRAGMENT_TAG).setIndicator(getString(R.string.settings_chart_by_time));
+        tabsAdapter.addTab(chartTimeTabSpec, ChartTimeFragment.class, null);
+
+        TabSpec chartDistanceTabSpec = tabHost.newTabSpec(ChartDistanceFragment.CHART_FRAGMENT_TAG).setIndicator(getString(R.string.settings_chart_by_distance));
+        tabsAdapter.addTab(chartDistanceTabSpec, ChartDistanceFragment.class, null);
 
         if (savedInstanceState != null) {
             tabHost.setCurrentTabByTag(savedInstanceState.getString(CURRENT_TAB_TAG_KEY));

src/main/java/de/dennisguse/opentracks/fragments/ChartDistanceFragment.java

@@ -0,0 +1,10 @@
+package de.dennisguse.opentracks.fragments;
+
+public class ChartDistanceFragment extends ChartFragment {
+
+    public static final String CHART_FRAGMENT_TAG = ChartDistanceFragment.class.getSimpleName();
+
+    public ChartDistanceFragment() {
+        super(true);
+    }
+}

src/main/java/de/dennisguse/opentracks/fragments/ChartFragment.java

@@ -25,6 +25,7 @@ import android.view.ViewGroup.LayoutParams;
 import android.widget.ZoomControls;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentActivity;
@@ -54,9 +55,9 @@ import de.dennisguse.opentracks.util.UnitConversions;
  * @author Sandor Dornbush
  * @author Rodrigo Damazio
  */
-public class ChartFragment extends Fragment implements TrackDataListener {
+public abstract class ChartFragment extends Fragment implements TrackDataListener {
 
-    public static final String CHART_FRAGMENT_TAG = "chartFragment";
+    private static final String STATE_CHART_VIEW_BY_DISTANCE_KEY = "chartViewByDistance";
 
     private final ArrayList<double[]> pendingPoints = new ArrayList<>();
 
@@ -71,7 +72,7 @@ public class ChartFragment extends Fragment implements TrackDataListener {
     private int recordingDistanceInterval;
 
     // Modes of operation
-    private boolean chartByDistance = true;
+    private boolean chartByDistance;
     private boolean[] chartShow = new boolean[]{true, true, true, true, true, true};
 
     // UI elements
@@ -95,16 +96,18 @@ public class ChartFragment extends Fragment implements TrackDataListener {
         }
     };
 
+    public ChartFragment(boolean chartByDistance) {
+        this.chartByDistance = chartByDistance;
+    }
+
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
         recordingDistanceInterval = PreferencesUtils.getRecordingDistanceIntervalDefault(getContext());
 
-        /*
-         * Create a chartView here to store data thus won't need to reload all the data on every onStart or onResume.
-         */
-        chartView = new ChartView(getActivity());
+        // Create a chartView here to store data thus won't need to reload all the data on every onStart or onResume.
+        chartView = new ChartView(getActivity(), chartByDistance);
     }
 
     @Override
@@ -129,7 +132,7 @@ public class ChartFragment extends Fragment implements TrackDataListener {
     @Override
     public void onStart() {
         super.onStart();
-        ViewGroup layout = getActivity().findViewById(R.id.chart_view_layout);
+        ViewGroup layout = getView().findViewById(R.id.chart_view_layout);
         LayoutParams layoutParams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
         layout.addView(chartView, layoutParams);
     }
@@ -151,10 +154,24 @@ public class ChartFragment extends Fragment implements TrackDataListener {
     @Override
     public void onStop() {
         super.onStop();
-        ViewGroup layout = getActivity().findViewById(R.id.chart_view_layout);
+        ViewGroup layout = getView().findViewById(R.id.chart_view_layout);
         layout.removeView(chartView);
     }
 
+    @Override
+    public void onSaveInstanceState(@NonNull Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putBoolean(STATE_CHART_VIEW_BY_DISTANCE_KEY, chartByDistance);
+    }
+
+    @Override
+    public void onViewStateRestored(@Nullable Bundle savedInstanceState) {
+        super.onViewStateRestored(savedInstanceState);
+        if (savedInstanceState != null) {
+            chartByDistance = savedInstanceState.getBoolean(STATE_CHART_VIEW_BY_DISTANCE_KEY);
+        }
+    }
+
     @Override
     public void onTrackUpdated(Track track) {
         if (isResumed()) {
@@ -304,12 +321,6 @@ public class ChartFragment extends Fragment implements TrackDataListener {
      */
     private void checkChartSettings() {
         boolean needUpdate = false;
-        if (chartByDistance != PreferencesUtils.isChartByDistance(getActivity())) {
-            chartByDistance = !chartByDistance;
-            chartView.setChartByDistance(chartByDistance);
-            reloadTrackDataHub();
-            needUpdate = true;
-        }
         if (setSeriesEnabled(ChartView.ELEVATION_SERIES, PreferencesUtils.shouldChartShowElevation(getActivity()))) {
             needUpdate = true;
         }

src/main/java/de/dennisguse/opentracks/fragments/ChartTimeFragment.java

@@ -0,0 +1,10 @@
+package de.dennisguse.opentracks.fragments;
+
+public class ChartTimeFragment extends ChartFragment {
+
+    public static final String CHART_FRAGMENT_TAG = ChartTimeFragment.class.getSimpleName();
+
+    public ChartTimeFragment() {
+        super(false);
+    }
+}

src/main/java/de/dennisguse/opentracks/services/LocationManagerConnector.java

@@ -33,10 +33,6 @@ public class LocationManagerConnector {
     private final Handler handler;
     private final LocationManager locationManager;
 
-    private LocationListener requestLocationUpdates;
-    private float requestLocationUpdatesDistance;
-    private long requestLocationUpdatesTime;
-
     public LocationManagerConnector(Context context, Looper looper) {
         this.handler = new Handler(looper);
 
@@ -55,10 +51,7 @@ public class LocationManagerConnector {
             @Override
             @SuppressLint("MissingPermission")
             public void run() {
-                requestLocationUpdatesTime = minTime;
-                requestLocationUpdatesDistance = minDistance;
-                requestLocationUpdates = locationListener;
-                locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, requestLocationUpdatesTime, requestLocationUpdatesDistance, locationListener);
+                locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, minTime, minDistance, locationListener);
             }
         });
     }
@@ -70,6 +63,5 @@ public class LocationManagerConnector {
      */
     public void removeLocationUpdates(final LocationListener locationListener) {
         locationManager.removeUpdates(locationListener);
-        requestLocationUpdates = null;
     }
 }

src/main/java/de/dennisguse/opentracks/services/TrackRecordingService.java

@@ -16,9 +16,6 @@
 
 package de.dennisguse.opentracks.services;
 
-import android.app.Notification;
-import android.app.NotificationChannel;
-import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.app.Service;
 import android.content.Context;
@@ -30,7 +27,6 @@ import android.location.Location;
 import android.location.LocationListener;
 import android.location.LocationManager;
 import android.net.Uri;
-import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
@@ -38,7 +34,6 @@ import android.os.PowerManager.WakeLock;
 import android.util.Log;
 
 import androidx.annotation.VisibleForTesting;
-import androidx.core.app.NotificationCompat;
 import androidx.core.app.TaskStackBuilder;
 
 import java.util.concurrent.ExecutorService;
@@ -80,13 +75,13 @@ import de.dennisguse.opentracks.util.UnitConversions;
 public class TrackRecordingService extends Service {
 
     // The name of extra intent property to indicate whether we want to resume a previously recorded track.
-    public static final String RESUME_TRACK_EXTRA_NAME = "de.dennisguse.opentracks.RESUME_TRACK";
+    public static final String RESUME_TRACK_EXTRA_NAME = "RESUME_TRACK";
+    private static final int NOTIFICATION_ID = 123;
 
     public static final double PAUSE_LATITUDE = 100.0;
     public static final double RESUME_LATITUDE = 200.0;
 
     // Anything faster than that (in meters per second) will be considered moving.
-
     public static final double MAX_NO_MOVEMENT_SPEED = 0.224;
     @VisibleForTesting
     static final int MAX_AUTO_RESUME_TRACK_RETRY_ATTEMPTS = 3;
@@ -95,13 +90,13 @@ public class TrackRecordingService extends Service {
     private static final long ONE_MINUTE = (long) (UnitConversions.MIN_TO_S * UnitConversions.S_TO_MS);
     // The following variables are set in onCreate:
     private ExecutorService executorService;
-    private Context context;
     private ContentProviderUtils contentProviderUtils;
     private Handler handler;
     private LocationManagerConnector locationManagerConnector;
     private PeriodicTaskExecutor voiceExecutor;
     private PeriodicTaskExecutor splitExecutor;
     private SharedPreferences sharedPreferences;
+    private TrackRecordingServiceNotificationManager notificationManager;
     private long recordingTrackId;
     private boolean recordingTrackPaused;
     private LocationListenerPolicy locationListenerPolicy;
@@ -117,10 +112,11 @@ public class TrackRecordingService extends Service {
     private final OnSharedPreferenceChangeListener sharedPreferenceChangeListener = new OnSharedPreferenceChangeListener() {
         @Override
         public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
-            if (PreferencesUtils.isKey(context, R.string.recording_track_id_key, key)) {
+            Context context = TrackRecordingService.this;
+            if (PreferencesUtils.isKey(TrackRecordingService.this, R.string.recording_track_id_key, key)) {
                 // Only through the TrackRecordingService can one stop a recording and set the recordingTrackId to -1L.
-                if (PreferencesUtils.isRecording(context)) {
-                    recordingTrackId = PreferencesUtils.getRecordingTrackId(context);
+                if (PreferencesUtils.isRecording(TrackRecordingService.this)) {
+                    recordingTrackId = PreferencesUtils.getRecordingTrackId(TrackRecordingService.this);
                 }
             }
             if (PreferencesUtils.isKey(context, R.string.recording_track_paused_key, key)) {
@@ -218,7 +214,6 @@ public class TrackRecordingService extends Service {
     public void onCreate() {
         super.onCreate();
         executorService = Executors.newSingleThreadExecutor();
-        context = this;
         contentProviderUtils = ContentProviderUtils.Factory.get(this);
         handler = new Handler();
         locationManagerConnector = new LocationManagerConnector(this, handler.getLooper());
@@ -226,6 +221,7 @@ public class TrackRecordingService extends Service {
         splitExecutor = new PeriodicTaskExecutor(this, new SplitPeriodicTaskFactory());
         sharedPreferences = PreferencesUtils.getSharedPreferences(this);
         sharedPreferences.registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener);
+        notificationManager = new TrackRecordingServiceNotificationManager(this);
 
         // onSharedPreferenceChanged might not set recordingTrackId.
         recordingTrackId = PreferencesUtils.RECORDING_TRACK_ID_DEFAULT;
@@ -267,7 +263,7 @@ public class TrackRecordingService extends Service {
         }
 
         // Reverse order from onCreate
-        showNotification(false);
+        showNotification(false); //TODO Why?
 
         handler.removeCallbacks(registerLocationRunnable);
         unregisterLocationListener();
@@ -400,40 +396,6 @@ public class TrackRecordingService extends Service {
         return Long.parseLong(uri.getLastPathSegment());
     }
 
-    /**
-     * Starts the service as a foreground service.
-     *
-     * @param pendingIntent the notification pending intent
-     * @param messageId     the notification message id
-     */
-    @VisibleForTesting
-    protected void startForegroundService(PendingIntent pendingIntent, int messageId) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-            NotificationChannel notificationChannel = new NotificationChannel(getString(R.string.app_name), getString(R.string.app_name), NotificationManager.IMPORTANCE_DEFAULT);
-            NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
-            if (manager != null) {
-                manager.createNotificationChannel(notificationChannel);
-            }
-        }
-        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, getString(R.string.app_name))
-                .setContentIntent(pendingIntent)
-                .setContentText(getString(messageId))
-                .setContentTitle(getString(R.string.app_name))
-                .setOngoing(true)
-                .setSmallIcon(R.drawable.ic_logo_color_24dp)
-                .setCategory(Notification.CATEGORY_SERVICE)
-                .setWhen(System.currentTimeMillis());
-        startForeground(1, builder.build());
-    }
-
-    /**
-     * Stops the service as a foreground service.
-     */
-    @VisibleForTesting
-    protected void stopForegroundService() {
-        stopForeground(true);
-    }
-
     /**
      * Handles start command.
      *
@@ -468,12 +430,12 @@ public class TrackRecordingService extends Service {
         }
         PreferencesUtils.incrementAutoResumeTrackCurrentRetryDefault(this);
 
-        if (autoResumeTrackTimeout == Integer.parseInt(context.getResources().getString(R.string.auto_resume_track_timeout_never))) {
+        if (autoResumeTrackTimeout == Integer.parseInt(getResources().getString(R.string.auto_resume_track_timeout_never))) {
             Log.d(TAG, "Not resuming. Auto-resume track timeout set to never.");
             return false;
         }
 
-        if (autoResumeTrackTimeout == Integer.parseInt(context.getResources().getString(R.string.auto_resume_track_timeout_always))) {
+        if (autoResumeTrackTimeout == Integer.parseInt(getResources().getString(R.string.auto_resume_track_timeout_always))) {
             Log.d(TAG, "Resuming. Auto-resume track timeout set to always.");
             return true;
         }
@@ -677,6 +639,8 @@ public class TrackRecordingService extends Service {
         }
 
         endRecording(false, recordingTrackId);
+
+        notificationManager.updateContent(getString(R.string.generic_paused));
     }
 
     /**
@@ -763,6 +727,8 @@ public class TrackRecordingService extends Service {
                 return;
             }
 
+            notificationManager.updateLocation(this, location, recordingGpsAccuracy);
+
             if (!location.hasAccuracy() || location.getAccuracy() >= recordingGpsAccuracy) {
                 Log.d(TAG, "Ignore onLocationChangedAsync. Poor accuracy.");
                 return;
@@ -798,10 +764,7 @@ public class TrackRecordingService extends Service {
             }
 
             if (!LocationUtils.isValidLocation(lastValidTrackPoint)) {
-                /*
-                 * Should not happen. The current segment should have a location. Just
-                 * insert the current location.
-                 */
+                // Should not happen. The current segment should have a location. Just insert the current location.
                 insertLocation(track, location, null);
                 lastLocation = location;
                 return;
@@ -948,33 +911,33 @@ public class TrackRecordingService extends Service {
         }
     }
 
-    /**
-     * Shows the notification.
-     *
-     * @param isGpsStarted true if GPS is started
-     */
     private void showNotification(boolean isGpsStarted) {
-        if (isRecording()) {
-            if (isPaused()) {
-                stopForegroundService();
-            } else {
-                Intent intent = IntentUtils.newIntent(this, TrackDetailActivity.class)
-                        .putExtra(TrackDetailActivity.EXTRA_TRACK_ID, recordingTrackId);
-                PendingIntent pendingIntent = TaskStackBuilder.create(this)
-                        .addParentStack(TrackDetailActivity.class).addNextIntent(intent)
-                        .getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
-                startForegroundService(pendingIntent, R.string.track_record_notification);
-            }
-        } else {
-            // Not recording
-            if (isGpsStarted) {
-                Intent intent = IntentUtils.newIntent(this, TrackListActivity.class);
-                PendingIntent pendingIntent = TaskStackBuilder.create(this)
-                        .addNextIntent(intent).getPendingIntent(0, 0);
-                startForegroundService(pendingIntent, R.string.gps_starting);
-            } else {
-                stopForegroundService();
-            }
+        if ((isRecording() && isPaused()) || (!isRecording() && !isGpsStarted)) {
+            stopForeground(true);
+        }
+
+        if (isRecording() && !isPaused()) {
+            Intent intent = IntentUtils.newIntent(this, TrackDetailActivity.class)
+                    .putExtra(TrackDetailActivity.EXTRA_TRACK_ID, recordingTrackId);
+            PendingIntent pendingIntent = TaskStackBuilder.create(this)
+                    .addParentStack(TrackDetailActivity.class)
+                    .addNextIntent(intent)
+                    .getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
+
+            notificationManager.updatePendingIntent(pendingIntent);
+            notificationManager.updateContent(getString(R.string.gps_starting));
+            startForeground(NOTIFICATION_ID, notificationManager.getNotification());
+        }
+        if (!isRecording() && isGpsStarted) {
+            Intent intent = IntentUtils.newIntent(this, TrackListActivity.class);
+            PendingIntent pendingIntent = TaskStackBuilder.create(this)
+                    .addNextIntent(intent)
+                    .getPendingIntent(0, 0);
+
+            notificationManager.updatePendingIntent(pendingIntent);
+            notificationManager.updateContent(getString(R.string.gps_starting));
+
+            startForeground(NOTIFICATION_ID, notificationManager.getNotification());
         }
     }
 

src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceNotificationManager.java

@@ -0,0 +1,94 @@
+package de.dennisguse.opentracks.services;
+
+import android.app.Notification;
+import android.app.NotificationChannel;
+import android.app.NotificationManager;
+import android.app.PendingIntent;
+import android.content.Context;
+import android.location.Location;
+import android.os.Build;
+
+import androidx.annotation.VisibleForTesting;
+import androidx.core.app.NotificationCompat;
+
+import de.dennisguse.opentracks.R;
+import de.dennisguse.opentracks.util.PreferencesUtils;
+import de.dennisguse.opentracks.util.StringUtils;
+
+/**
+ * Manages the content of the notification shown by {@link TrackRecordingService}.
+ */
+class TrackRecordingServiceNotificationManager {
+
+    private final static int NOTIFICATION_ID = 123;
+
+    private final static String CHANNEL_ID = TrackRecordingServiceNotificationManager.class.getSimpleName();
+
+    private NotificationCompat.Builder notificationBuilder;
+
+    private NotificationManager notificationManager;
+
+    private boolean previousLocationWasAccurate = true;
+
+    TrackRecordingServiceNotificationManager(Context context) {
+        notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            NotificationChannel notificationChannel = new NotificationChannel(CHANNEL_ID, context.getString(R.string.app_name), NotificationManager.IMPORTANCE_HIGH);
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+                notificationChannel.setAllowBubbles(true);
+            }
+
+            notificationManager.createNotificationChannel(notificationChannel);
+        }
+
+        notificationBuilder = new NotificationCompat.Builder(context, CHANNEL_ID);
+        notificationBuilder
+                .setDefaults(NotificationCompat.DEFAULT_ALL)
+                .setPriority(NotificationCompat.PRIORITY_MAX)
+                .setOnlyAlertOnce(true)
+                .setOngoing(true)
+                .setCategory(NotificationCompat.CATEGORY_SERVICE)
+                .setContentTitle(context.getString(R.string.app_name))
+                .setSmallIcon(R.drawable.ic_logo_color_24dp);
+    }
+
+    @VisibleForTesting
+    TrackRecordingServiceNotificationManager(NotificationManager notificationManager, NotificationCompat.Builder notificationBuilder) {
+        this.notificationManager = notificationManager;
+        this.notificationBuilder = notificationBuilder;
+    }
+
+    void updateContent(String content) {
+        notificationBuilder.setContentText(content);
+        updateNotification();
+    }
+
+    void updateLocation(Context context, Location location, int recordingGpsAccuracy) {
+        String formattedAccuracy = context.getString(R.string.value_none);
+        if (location.hasAccuracy()) {
+            formattedAccuracy = StringUtils.formatDistance(context, location.getAccuracy(), PreferencesUtils.isMetricUnits(context));
+
+            boolean currentLocationWasAccurate = location.getAccuracy() < recordingGpsAccuracy;
+            boolean shouldAlert = !currentLocationWasAccurate && previousLocationWasAccurate;
+            notificationBuilder.setOnlyAlertOnce(!shouldAlert);
+            previousLocationWasAccurate = currentLocationWasAccurate;
+        }
+
+        notificationBuilder.setContentText(context.getString(R.string.track_recording_notification_accuracy, formattedAccuracy));
+        updateNotification();
+        notificationBuilder.setOnlyAlertOnce(true);
+    }
+
+    void updatePendingIntent(PendingIntent pendingIntent) {
+        notificationBuilder.setContentIntent(pendingIntent);
+        updateNotification();
+    }
+
+    Notification getNotification() {
+        return notificationBuilder.build();
+    }
+
+    private void updateNotification() {
+        notificationManager.notify(NOTIFICATION_ID, getNotification());
+    }
+}

src/main/java/de/dennisguse/opentracks/services/tasks/AnnouncementPeriodicTask.java

@@ -34,6 +34,7 @@ import de.dennisguse.opentracks.services.TrackRecordingService;
 import de.dennisguse.opentracks.stats.TripStatistics;
 import de.dennisguse.opentracks.util.PreferencesUtils;
 import de.dennisguse.opentracks.util.StringUtils;
+import de.dennisguse.opentracks.util.TTSUtils;
 import de.dennisguse.opentracks.util.UnitConversions;
 
 /**
@@ -193,7 +194,7 @@ public class AnnouncementPeriodicTask implements PeriodicTask {
      * @param announcement the announcement
      */
     private void speakAnnouncement(String announcement) {
-        int result = audioManager.requestAudioFocus(null, TextToSpeech.Engine.DEFAULT_STREAM, AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK);
+        int result = audioManager.requestAudioFocus(null, TTSUtils.getTTSStream(), AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK);
         if (result == AudioManager.AUDIOFOCUS_REQUEST_FAILED) {
             Log.w(TAG, "Failed to request audio focus.");
         }

src/main/java/de/dennisguse/opentracks/util/LocationUtils.java

@@ -157,7 +157,7 @@ public class LocationUtils {
     }
 
     /**
-     * Checks if a given location is a valid (i.e. physically possible) locationon Earth.
+     * Checks if a given location is a valid (i.e. physically possible) location on Earth.
      * Note: The special separator locations (which have latitude = 100) will not qualify as valid.
      * Neither will locations with lat=0 and lng=0 as these are most likely "bad" measurements which often cause trouble.
      *

src/main/java/de/dennisguse/opentracks/util/PreferencesUtils.java

@@ -259,11 +259,6 @@ public class PreferencesUtils {
         return PreferencesUtils.getString(context, R.string.settings_sensor_bluetooth_heart_rate_key, PreferencesUtils.BLUETOOTH_SENSOR_DEFAULT);
     }
 
-    public static boolean isChartByDistance(Context context) {
-        final String CHART_X_AXIS_DEFAULT = context.getString(R.string.chart_x_axis_default);
-        return CHART_X_AXIS_DEFAULT.equals(getString(context, R.string.chart_x_axis_key, CHART_X_AXIS_DEFAULT));
-    }
-
     public static boolean shouldChartShowCadence(Context context) {
         final boolean CHART_SHOW_CADENCE = context.getResources().getBoolean(R.bool.chart_show_cadence_default);
         return PreferencesUtils.getBoolean(context, R.string.chart_show_cadence_key, CHART_SHOW_CADENCE);

src/main/java/de/dennisguse/opentracks/util/TTSUtils.java

@@ -0,0 +1,13 @@
+package de.dennisguse.opentracks.util;
+
+import android.speech.tts.TextToSpeech;
+
+public class TTSUtils {
+
+    private TTSUtils() {
+    }
+
+    public static int getTTSStream() {
+        return TextToSpeech.Engine.DEFAULT_STREAM;
+    }
+}

src/main/res/layout/help.xml

@@ -0,0 +1,188 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <include layout="@layout/toolbar" />
+
+    <ScrollView
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical"
+            android:padding="20dp">
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_feature_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_feature_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_track_map_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:linksClickable="true"
+                android:text="@string/help_track_map_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_data_statistics_customized_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_data_statistics_customized_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_recording_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_recording_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_gps_imprecise_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_gps_imprecise_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_heart_rate_sensors_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_heart_rate_sensors_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_storage_pictures_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_storage_pictures_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_track_export_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_track_export_content" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_data_upload_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/generic_no" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_data_google_play_services_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/generic_no" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_data_online_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/generic_no" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dp"
+                android:text="@string/help_data_storage_title"
+                android:textStyle="bold" />
+
+            <TextView
+                style="@style/TextMedium"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:text="@string/help_data_storage_content" />
+        </LinearLayout>
+    </ScrollView>
+
+</LinearLayout>

src/main/res/values/settings.xml

@@ -114,19 +114,6 @@
         <item>@string/auto_resume_track_timeout_always</item>
     </string-array>
 
-    <string name="chart_x_axis_key" translatable="false">chartXAxis</string>
-    <string name="chart_x_axis_default" translatable="false">@string/chart_x_axis_distance</string>
-    <string-array name="chart_x_axis_values">
-        <item>@string/chart_x_axis_distance</item>
-        <item>@string/chart_x_axis_time</item>
-    </string-array>
-    <string name="chart_x_axis_time" translatable="false">TIME</string>
-    <string name="chart_x_axis_distance" translatable="false">DISTANCE</string>
-    <string-array name="chart_x_axis_options">
-        <item>@string/settings_chart_by_distance</item>
-        <item>@string/settings_chart_by_time</item>
-    </string-array>
-
     <string name="split_frequency_key" translatable="false">splitFrequency</string>
     <string name="split_frequency_default" translatable="false">@string/frequency_off</string>
     <string name="voice_frequency_key" translatable="false">voiceFrequency</string>

src/main/res/values/settings_deprecated.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- This file contains old and now unused settings. -->
+    <!-- It is recommended not to reuse the keys. -->
+
+    <string name="chart_x_axis_key" translatable="false">chartXAxis</string>
+    <string name="chart_x_axis_default" translatable="false">@string/chart_x_axis_distance</string>
+    <string-array name="chart_x_axis_values">
+        <item>@string/chart_x_axis_distance</item>
+        <item>@string/chart_x_axis_time</item>
+    </string-array>
+    <string name="chart_x_axis_time" translatable="false">TIME</string>
+    <string name="chart_x_axis_distance" translatable="false">DISTANCE</string>
+    <string-array name="chart_x_axis_options">
+        <item>@string/settings_chart_by_distance</item>
+        <item>@string/settings_chart_by_time</item>
+    </string-array>
+</resources>

src/main/res/values/strings.xml

@@ -38,6 +38,95 @@ limitations under the License.
     Libraries
   </string>
 
+  <!-- Help -->
+  <string name="help_feature_title">
+    OpenTracks has the following features:
+  </string>
+  <string name="help_feature_content">
+* Create markers (incl. pictures)\n
+* Heart rate sensor (Bluetooth LE)\n
+* Voice announcements by time or distance\n
+* While recording, show on lock screen\n
+* Share tracks
+  </string>
+
+  <string name="help_data_statistics_customized_title">
+    Can the statistics view be customized?
+  </string>
+  <string name="help_data_statistics_customized_content">
+    Yes, it can be customized in the Settings.
+  </string>
+
+  <string name="help_recording_title">
+    How does OpenTracks record data?
+  </string>
+  <string name="help_recording_content">
+    OpenTracks uses the GPS sensor of the device to record the location continuously.
+  </string>
+
+  <string name="help_gps_imprecise_title">
+    Statistics (e.g., speed) reported by OpenTracks are imprecise?
+  </string>
+  <string name="help_gps_imprecise_content">
+    OpenTracks directly uses the data provided by the GPS of the mobile device.
+    If the GPS device reports inaccurate locations, OpenTracks cannot do anything about it.
+  </string>
+
+  <string name="help_heart_rate_sensors_title">
+    Which heart rate sensors does OpenTracks support?
+  </string>
+  <string name="help_heart_rate_sensors_content">
+    OpenTracks should work with any Bluetooth LE heart sensor that support streaming the data in real-time.
+    Smartwatches that store the heart rate data are not supported.
+  </string>
+
+  <string name="help_track_map_title">
+    How to show a track on a map?
+  </string>
+  <string name="help_track_map_content">
+    This requires a 3rd party application to be installed that can consume KMZ-encoded geo data.
+    This works well with <a href="http://osmand.net/">OsmAnd~</a> and <a href="https://maps.me/">Maps.ME</a>.
+    In fact, an App needs to support <i>ACTION_VIEW</i> with MIME <i>application/vnd.google-earth.kmz</i>.
+    At the moment, the recorded locations as well as the timestamps are send to an App while pictures and sensor data are not shared.
+  </string>
+
+  <string name="help_storage_pictures_title">
+    How does OpenTracks store pictures that were taken as markers?
+  </string>
+  <string name="help_storage_pictures_content">
+    These are stored directly on the file system.
+  </string>
+
+  <string name="help_track_export_title">
+    How can I export/share recorded tracks?
+  </string>
+  <string name="help_track_export_content">
+    Tracks can be exported from the Settings as KMZ, KML, or GPX.
+    KMZ contains all data incl. images, while KML contains only the sensor data, and GPX only the location.
+    Tracks shared via the <i>share icon</i> are shared as KMZ and any App can be used to send the data.
+  </string>
+
+  <string name="help_data_upload_title">
+    Can OpenTracks upload the data automatically?
+  </string>
+
+  <string name="help_data_google_play_services_title">
+    Does OpenTracks require/use Google Play Service?
+  </string>
+
+  <string name="help_data_online_title">
+    Does OpenTracks use online services?
+  </string>
+
+  <string name="help_data_storage_title">
+    How does OpenTracks store sensor data?
+  </string>
+  <string name="help_data_storage_content">
+    OpenTracks stores sensor data per recorded location.
+    In terms of a heart rate sensor this means that only <i>one</i> heart rate measurement is stored per location.
+    If you are standing still or are indoors, no sensor data will be recorded (but it will be shown).
+  </string>
+
   <!-- Activity Type -->
     <string name="activity_type_airplane" translation_description="When entering an 'Activity type', in the auto-complete text box, the
       completion suggestion for airplane.">
@@ -1425,6 +1514,9 @@ limitations under the License.
     <string name="track_record_notification" translation_description="When recording a track, the message on the OpenTracks notification
       informing the user that OpenTracks is actively recording his track.">
     Recording your track&#8230;
+  </string>
+  <string name="track_recording_notification_accuracy">
+      Location accuracy: %1$s
   </string>
     <string name="track_markers" translation_description="Title indicating a particular track's markers.
 

src/main/res/xml/settings.xml

@@ -17,6 +17,14 @@ limitations under the License.
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:title="@string/menu_settings">
 
+    <PreferenceCategory android:title="@string/menu_help">
+        <Preference android:title="@string/menu_help">
+            <intent
+                android:targetClass="de.dennisguse.opentracks.HelpActivity"
+                android:targetPackage="@string/applicationId" />
+        </Preference>
+    </PreferenceCategory>
+
     <PreferenceCategory android:title="@string/track_detail_stats_tab">
         <ListPreference
             android:defaultValue="@string/stats_units_default"
@@ -46,13 +54,6 @@ limitations under the License.
     </PreferenceCategory>
 
     <PreferenceCategory android:title="@string/track_detail_chart_tab">
-        <ListPreference
-            android:defaultValue="@string/chart_x_axis_default"
-            android:entries="@array/chart_x_axis_options"
-            android:entryValues="@array/chart_x_axis_values"
-            android:key="@string/chart_x_axis_key"
-            android:title="@string/settings_chart_x_axis"
-            app:useSimpleSummaryProvider="true" />
         <CheckBoxPreference
             android:defaultValue="true"
             android:key="@string/chart_show_elevation_key"