Miscellaneous code cleanup

app/src/main/java/org/y20k/trackbook/MainActivity.kt

@@ -78,13 +78,13 @@ class MainActivity : AppCompatActivity() {
         navHostFragment.navController.addOnDestinationChangedListener { _, destination, _ ->
             when (destination.id) {
                 R.id.fragment_track -> {
-                    runOnUiThread(Runnable() {
+                    runOnUiThread {
-                        run() {
+                        run {
                             // mark menu item "Tracks" as checked
                             bottomNavigationView.menu.findItem(R.id.tracklist_fragment)
                                 .setChecked(true)
                         }
-                    })
+                    }
                 }
                 else -> {
                     // do nothing
@@ -111,7 +111,7 @@ class MainActivity : AppCompatActivity() {
      * Defines the listener for changes in shared preferences
      */
     private val sharedPreferenceChangeListener =
-        SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->
+        SharedPreferences.OnSharedPreferenceChangeListener { _, key ->
             when (key) {
                 Keys.PREF_THEME_SELECTION -> {
                     AppThemeHelper.setTheme(PreferencesHelper.loadThemeSelection(this@MainActivity))

app/src/main/java/org/y20k/trackbook/MapFragment.kt

@@ -281,7 +281,7 @@ class MapFragment : Fragment(), YesNoDialog.YesNoDialogListener, MapOverlay.Mark
 
     /* Opens a track in TrackFragment */
     private fun openTrack(tracklistElement: TracklistElement) {
-        val bundle: Bundle = Bundle()
+        val bundle = Bundle()
         bundle.putString(Keys.ARG_TRACK_TITLE, tracklistElement.name)
         bundle.putString(Keys.ARG_TRACK_FILE_URI, tracklistElement.trackUriString)
         bundle.putString(Keys.ARG_GPX_FILE_URI, tracklistElement.gpxUriString)
@@ -294,7 +294,7 @@ class MapFragment : Fragment(), YesNoDialog.YesNoDialogListener, MapOverlay.Mark
      * Defines the listener for changes in shared preferences
      */
     private val sharedPreferenceChangeListener =
-        SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->
+        SharedPreferences.OnSharedPreferenceChangeListener { _, key ->
             when (key) {
                 Keys.PREF_TRACKING_STATE -> {
                     if (activity != null) {

app/src/main/java/org/y20k/trackbook/SettingsFragment.kt

@@ -63,7 +63,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         val screen = preferenceManager.createPreferenceScreen(context)
 
         // set up "Restrict to GPS" preference
-        val preferenceGpsOnly: SwitchPreferenceCompat = SwitchPreferenceCompat(activity as Context)
+        val preferenceGpsOnly = SwitchPreferenceCompat(activity as Context)
         preferenceGpsOnly.title = getString(R.string.pref_gps_only_title)
         preferenceGpsOnly.setIcon(R.drawable.ic_gps_24dp)
         preferenceGpsOnly.key = Keys.PREF_GPS_ONLY
@@ -72,8 +72,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         preferenceGpsOnly.setDefaultValue(false)
 
         // set up "Use Imperial Measurements" preference
-        val preferenceImperialMeasurementUnits: SwitchPreferenceCompat =
+        val preferenceImperialMeasurementUnits = SwitchPreferenceCompat(activity as Context)
-            SwitchPreferenceCompat(activity as Context)
         preferenceImperialMeasurementUnits.title =
             getString(R.string.pref_imperial_measurement_units_title)
         preferenceImperialMeasurementUnits.setIcon(R.drawable.ic_square_foot_24px)
@@ -85,7 +84,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         preferenceImperialMeasurementUnits.setDefaultValue(LengthUnitHelper.useImperialUnits())
 
         // set up "App Theme" preference
-        val preferenceThemeSelection: ListPreference = ListPreference(activity as Context)
+        val preferenceThemeSelection = ListPreference(activity as Context)
         preferenceThemeSelection.title = getString(R.string.pref_theme_selection_title)
         preferenceThemeSelection.setIcon(R.drawable.ic_smartphone_24dp)
         preferenceThemeSelection.key = Keys.PREF_THEME_SELECTION
@@ -107,9 +106,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
             if (preference is ListPreference) {
                 val index: Int = preference.entryValues.indexOf(newValue)
                 preferenceThemeSelection.summary =
-                    "${getString(R.string.pref_theme_selection_summary)} ${preference.entries.get(
+                    "${getString(R.string.pref_theme_selection_summary)} ${preference.entries[index]}"
-                        index
-                    )}"
                 return@setOnPreferenceChangeListener true
             } else {
                 return@setOnPreferenceChangeListener false
@@ -117,7 +114,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         }
 
         // set up "Delete Non-Starred" preference
-        val preferenceDeleteNonStarred: Preference = Preference(activity as Context)
+        val preferenceDeleteNonStarred = Preference(activity as Context)
         preferenceDeleteNonStarred.title = getString(R.string.pref_delete_non_starred_title)
         preferenceDeleteNonStarred.setIcon(R.drawable.ic_delete_24dp)
         preferenceDeleteNonStarred.summary = getString(R.string.pref_delete_non_starred_summary)
@@ -132,7 +129,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         }
 
         // set up "Accuracy Threshold" preference
-        val preferenceAccuracyThreshold: SeekBarPreference = SeekBarPreference(activity as Context)
+        val preferenceAccuracyThreshold = SeekBarPreference(activity as Context)
         preferenceAccuracyThreshold.title = getString(R.string.pref_accuracy_threshold_title)
         preferenceAccuracyThreshold.setIcon(R.drawable.ic_timeline_24dp)
         preferenceAccuracyThreshold.key = Keys.PREF_LOCATION_ACCURACY_THRESHOLD
@@ -142,7 +139,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         preferenceAccuracyThreshold.setDefaultValue(Keys.DEFAULT_THRESHOLD_LOCATION_ACCURACY)
 
         // set up "Reset" preference
-        val preferenceResetAdvanced: Preference = Preference(activity as Context)
+        val preferenceResetAdvanced = Preference(activity as Context)
         preferenceResetAdvanced.title = getString(R.string.pref_reset_advanced_title)
         preferenceResetAdvanced.setIcon(R.drawable.ic_undo_24dp)
         preferenceResetAdvanced.summary = getString(R.string.pref_reset_advanced_summary)
@@ -152,7 +149,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         }
 
         // set up "App Version" preference
-        val preferenceAppVersion: Preference = Preference(context)
+        val preferenceAppVersion = Preference(context)
         preferenceAppVersion.title = getString(R.string.pref_app_version_title)
         preferenceAppVersion.setIcon(R.drawable.ic_info_24dp)
         preferenceAppVersion.summary =
@@ -174,7 +171,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         }
 
         // set up "Report Issue" preference
-        val preferenceReportIssue: Preference = Preference(context)
+        val preferenceReportIssue = Preference(context)
         preferenceReportIssue.title = getString(R.string.pref_report_issue_title)
         preferenceReportIssue.setIcon(R.drawable.ic_bug_report_24dp)
         preferenceReportIssue.summary = getString(R.string.pref_report_issue_summary)
@@ -189,21 +186,21 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
         }
 
         // set preference categories
-        val preferenceCategoryGeneral: PreferenceCategory = PreferenceCategory(activity as Context)
+        val preferenceCategoryGeneral = PreferenceCategory(activity as Context)
         preferenceCategoryGeneral.title = getString(R.string.pref_general_title)
         preferenceCategoryGeneral.contains(preferenceImperialMeasurementUnits)
         preferenceCategoryGeneral.contains(preferenceGpsOnly)
-        val preferenceCategoryMaintenance: PreferenceCategory =
+        val preferenceCategoryMaintenance =
             PreferenceCategory(activity as Context)
         preferenceCategoryMaintenance.title = getString(R.string.pref_maintenance_title)
         preferenceCategoryMaintenance.contains(preferenceDeleteNonStarred)
 
-        val preferenceCategoryAdvanced: PreferenceCategory = PreferenceCategory(activity as Context)
+        val preferenceCategoryAdvanced = PreferenceCategory(activity as Context)
         preferenceCategoryAdvanced.title = getString(R.string.pref_advanced_title)
         preferenceCategoryAdvanced.contains(preferenceAccuracyThreshold)
         preferenceCategoryAdvanced.contains(preferenceResetAdvanced)
 
-        val preferenceCategoryAbout: PreferenceCategory = PreferenceCategory(context)
+        val preferenceCategoryAbout = PreferenceCategory(context)
         preferenceCategoryAbout.title = getString(R.string.pref_about_title)
         preferenceCategoryAbout.contains(preferenceAppVersion)
         preferenceCategoryAbout.contains(preferenceReportIssue)
@@ -249,7 +246,7 @@ class SettingsFragment : PreferenceFragmentCompat(), YesNoDialog.YesNoDialogList
 
 
     /* Removes track and track files for given position - used by TracklistFragment */
-    fun deleteNonStarred(context: Context) {
+    private fun deleteNonStarred(context: Context) {
         val backgroundJob = Job()
         val uiScope = CoroutineScope(Dispatchers.Main + backgroundJob)
         uiScope.launch {

app/src/main/java/org/y20k/trackbook/TrackFragment.kt

@@ -64,10 +64,10 @@ class TrackFragment : Fragment(), RenameTrackDialog.RenameTrackListener,
         // get track
         val fileUriString: String =
             arguments?.getString(Keys.ARG_TRACK_FILE_URI, String()) ?: String()
-        if (fileUriString.isNotBlank()) {
+        track = if (fileUriString.isNotBlank()) {
-            track = FileHelper.readTrack(activity as Context, Uri.parse(fileUriString))
+            FileHelper.readTrack(Uri.parse(fileUriString))
         } else {
-            track = Track()
+            Track()
         }
     }
 
@@ -99,7 +99,7 @@ class TrackFragment : Fragment(), RenameTrackDialog.RenameTrackListener,
         }
         // set up delete button
         layout.deleteButton.setOnClickListener {
-            val dialogMessage: String =
+            val dialogMessage =
                 "${getString(R.string.dialog_yes_no_message_delete_recording)}\n\n- ${layout.trackNameView.text}"
             YesNoDialog(this@TrackFragment as YesNoDialog.YesNoDialogListener).show(
                 context = activity as Context,

app/src/main/java/org/y20k/trackbook/TrackerService.kt

@@ -48,7 +48,7 @@ import kotlin.coroutines.CoroutineContext
 /*
  * TrackerService class
  */
-class TrackerService() : Service(), CoroutineScope, SensorEventListener {
+class TrackerService : Service(), CoroutineScope, SensorEventListener {
 
     /* Define log tag */
     private val TAG: String = LogHelper.makeLogTag(TrackerService::class.java)
@@ -58,16 +58,16 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
     var trackingState: Int = Keys.STATE_TRACKING_NOT
     var gpsProviderActive: Boolean = false
     var networkProviderActive: Boolean = false
-    var useImperial: Boolean = false
+    private var useImperial: Boolean = false
-    var gpsOnly: Boolean = false
+    private var gpsOnly: Boolean = false
     var locationAccuracyThreshold: Int = Keys.DEFAULT_THRESHOLD_LOCATION_ACCURACY
     var currentBestLocation: Location = LocationHelper.getDefaultLocation()
-    var stepCountOffset: Float = 0f
+    private var stepCountOffset: Float = 0f
     var resumed: Boolean = false
     var track: Track = Track()
-    var gpsLocationListenerRegistered: Boolean = false
+    private var gpsLocationListenerRegistered: Boolean = false
-    var networkLocationListenerRegistered: Boolean = false
+    private var networkLocationListenerRegistered: Boolean = false
-    var bound: Boolean = false
+    private var bound: Boolean = false
     private val binder = LocalBinder()
     private val handler: Handler = Handler()
     private lateinit var locationManager: LocationManager
@@ -99,7 +99,7 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
         networkLocationListener = createLocationListener()
         trackingState = PreferencesHelper.loadTrackingState(this)
         currentBestLocation = LocationHelper.getLastKnownLocation(this)
-        track = FileHelper.readTrack(this, FileHelper.getTempFileUri(this))
+        track = FileHelper.readTrack(FileHelper.getTempFileUri(this))
         backgroundJob = Job()
         PreferenceManager.getDefaultSharedPreferences(this)
             .registerOnSharedPreferenceChangeListener(sharedPreferenceChangeListener)
@@ -194,7 +194,7 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
 
     /* Overrides onSensorChanged from SensorEventListener */
     override fun onSensorChanged(sensorEvent: SensorEvent?) {
-        var steps: Float = 0f
+        var steps = 0f
         if (sensorEvent != null) {
             if (stepCountOffset == 0f) {
                 // store steps previously recorded by the system
@@ -212,11 +212,11 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
     /* Resume tracking after stop/pause */
     fun resumeTracking() {
         // load temp track - returns an empty track if not available
-        track = FileHelper.readTrack(this, FileHelper.getTempFileUri(this))
+        track = FileHelper.readTrack(FileHelper.getTempFileUri(this))
         // try to mark last waypoint as stopover
         if (track.wayPoints.size > 0) {
             val lastWayPointIndex = track.wayPoints.size - 1
-            track.wayPoints.get(lastWayPointIndex).isStopOver = true
+            track.wayPoints[lastWayPointIndex].isStopOver = true
         }
         // set resumed flag
         resumed = true
@@ -480,7 +480,7 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
      * Defines the listener for changes in shared preferences
      */
     private val sharedPreferenceChangeListener =
-        SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->
+        SharedPreferences.OnSharedPreferenceChangeListener { _, key ->
             when (key) {
                 // preference "Restrict to GPS"
                 Keys.PREF_GPS_ONLY -> {
@@ -524,7 +524,6 @@ class TrackerService() : Service(), CoroutineScope, SensorEventListener {
         override fun run() {
             // add waypoint to track - step count is continuously updated in onSensorChanged
             val result: Pair<Track, Boolean> = TrackHelper.addWayPointToTrack(
-                this@TrackerService,
                 track,
                 currentBestLocation,
                 locationAccuracyThreshold,

app/src/main/java/org/y20k/trackbook/TrackingToggleTileService.kt

@@ -31,7 +31,7 @@ import org.y20k.trackbook.helpers.PreferencesHelper
 /*
  * TrackingToggleTileService class
  */
-class TrackingToggleTileService() : TileService() {
+class TrackingToggleTileService : TileService() {
 
     /* Define log tag */
     private val TAG: String = LogHelper.makeLogTag(TrackingToggleTileService::class.java)
@@ -52,11 +52,6 @@ class TrackingToggleTileService() : TileService() {
         updateTile()
     }
 
-    /* Overrides onTileRemoved from TileService */
-    override fun onTileRemoved() {
-        super.onTileRemoved()
-    }
-
 
     /* Overrides onStartListening from TileService (tile becomes visible) */
     override fun onStartListening() {
@@ -90,12 +85,6 @@ class TrackingToggleTileService() : TileService() {
     }
 
 
-    /* Overrides onDestroy from Service */
-    override fun onDestroy() {
-        super.onDestroy()
-    }
-
-
     /* Update quick settings tile */
     private fun updateTile() {
         val tile: Tile = qsTile
@@ -141,7 +130,7 @@ class TrackingToggleTileService() : TileService() {
      * Defines the listener for changes in shared preferences
      */
     private val sharedPreferenceChangeListener =
-        SharedPreferences.OnSharedPreferenceChangeListener { sharedPreferences, key ->
+        SharedPreferences.OnSharedPreferenceChangeListener { _, key ->
             when (key) {
                 Keys.PREF_TRACKING_STATE -> {
                     trackingState = PreferencesHelper.loadTrackingState(this)

app/src/main/java/org/y20k/trackbook/TracklistFragment.kt

@@ -82,7 +82,7 @@ class TracklistFragment : Fragment(), TracklistAdapter.TracklistAdapterListener,
             override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
                 // ask user
                 val adapterPosition: Int = viewHolder.adapterPosition
-                val dialogMessage: String =
+                val dialogMessage =
                     "${getString(R.string.dialog_yes_no_message_delete_recording)}\n\n- ${tracklistAdapter.getTrackName(
                         adapterPosition
                     )}"
@@ -107,7 +107,7 @@ class TracklistFragment : Fragment(), TracklistAdapter.TracklistAdapterListener,
 
     /* Overrides onTrackElementTapped from TracklistElementAdapterListener */
     override fun onTrackElementTapped(tracklistElement: TracklistElement) {
-        val bundle: Bundle = Bundle()
+        val bundle = Bundle()
         bundle.putString(Keys.ARG_TRACK_TITLE, tracklistElement.name)
         bundle.putString(Keys.ARG_TRACK_FILE_URI, tracklistElement.trackUriString)
         bundle.putString(Keys.ARG_GPX_FILE_URI, tracklistElement.gpxUriString)

app/src/main/java/org/y20k/trackbook/core/WayPoint.kt

@@ -45,7 +45,7 @@ data class WayPoint(
 
     /* Converts WayPoint into Location */
     fun toLocation(): Location {
-        val location: Location = Location(provider)
+        val location = Location(provider)
         location.latitude = latitude
         location.longitude = longitude
         location.altitude = altitude

app/src/main/java/org/y20k/trackbook/dialogs/ErrorDialog.kt

@@ -18,7 +18,6 @@
 package org.y20k.trackbook.dialogs
 
 import android.content.Context
-import android.content.DialogInterface
 import android.text.method.ScrollingMovementMethod
 import android.view.LayoutInflater
 import android.view.View
@@ -45,8 +44,7 @@ object ErrorDialog {
         errorDetails: String = String()
     ) {
         // prepare dialog builder
-        val builder: MaterialAlertDialogBuilder =
+        val builder = MaterialAlertDialogBuilder(context, R.style.AlertDialogTheme)
-            MaterialAlertDialogBuilder(context, R.style.AlertDialogTheme)
 
         // set title
         builder.setTitle(context.getString(errorTitle))
@@ -88,11 +86,11 @@ object ErrorDialog {
 
         // add okay button
         builder.setPositiveButton(
-            R.string.dialog_generic_button_okay,
+            R.string.dialog_generic_button_okay
-            DialogInterface.OnClickListener { _, _ ->
+        ) { _, _ ->
-                // listen for click on okay button
+            // listen for click on okay button
-                // do nothing
+            // do nothing
-            })
+        }
 
         // display error dialog
         builder.show()

app/src/main/java/org/y20k/trackbook/dialogs/RenameTrackDialog.kt

@@ -45,7 +45,7 @@ class RenameTrackDialog(private var renameTrackListener: RenameTrackListener) {
     /* Construct and show dialog */
     fun show(context: Context, trackName: String) {
         // prepare dialog builder
-        val builder: MaterialAlertDialogBuilder = MaterialAlertDialogBuilder(context)
+        val builder = MaterialAlertDialogBuilder(context)
 
         // get input field
         val inflater = LayoutInflater.from(context)

app/src/main/java/org/y20k/trackbook/dialogs/YesNoDialog.kt

@@ -75,8 +75,7 @@ class YesNoDialog(private var yesNoDialogListener: YesNoDialogListener) {
     ) {
 
         // prepare dialog builder
-        val builder: MaterialAlertDialogBuilder =
+        val builder = MaterialAlertDialogBuilder(context, R.style.AlertDialogTheme)
-            MaterialAlertDialogBuilder(context, R.style.AlertDialogTheme)
 
         // set title and message
         builder.setMessage(messageString)
@@ -98,7 +97,7 @@ class YesNoDialog(private var yesNoDialogListener: YesNoDialogListener) {
         }
 
         // handle outside-click as "no"
-        builder.setOnCancelListener() {
+        builder.setOnCancelListener {
             yesNoDialogListener.onYesNoDialog(type, false, payload, payloadString)
         }
 

app/src/main/java/org/y20k/trackbook/extensions/SharedPreferencesExt.kt

@@ -19,13 +19,15 @@ package org.y20k.trackbook.extensions
 
 
 import android.content.SharedPreferences
+import java.lang.Double.doubleToRawLongBits
+import java.lang.Double.longBitsToDouble
 
 
 /* Puts a Double value in SharedPreferences */
 fun SharedPreferences.Editor.putDouble(key: String, double: Double) =
-    putLong(key, java.lang.Double.doubleToRawLongBits(double))
+    this.putLong(key, doubleToRawLongBits(double))
 
 
 /* gets a Double value from SharedPreferences */
 fun SharedPreferences.getDouble(key: String, default: Double) =
-    java.lang.Double.longBitsToDouble(getLong(key, java.lang.Double.doubleToRawLongBits(default)))
+    longBitsToDouble(getLong(key, doubleToRawLongBits(default)))

app/src/main/java/org/y20k/trackbook/helpers/DateTimeHelper.kt

@@ -34,7 +34,7 @@ object DateTimeHelper {
 
     /* Converts milliseconds to mm:ss or hh:mm:ss */
     fun convertToReadableTime(context: Context, milliseconds: Long): String {
-        var timeString: String = String()
+        val timeString: String
         val hours: Long = TimeUnit.MILLISECONDS.toHours(milliseconds)
         val minutes: Long =
             TimeUnit.MILLISECONDS.toMinutes(milliseconds) % TimeUnit.HOURS.toMinutes(1)
@@ -44,14 +44,14 @@ object DateTimeHelper {
         val m: String = context.getString(R.string.abbreviation_minutes)
         val s: String = context.getString(R.string.abbreviation_seconds)
 
-        when (milliseconds >= Keys.ONE_HOUR_IN_MILLISECONDS) {
+        timeString = when (milliseconds >= Keys.ONE_HOUR_IN_MILLISECONDS) {
             // CASE: format hh:mm:ss
             true -> {
-                timeString = "$hours $h $minutes $m $seconds $s"
+                "$hours $h $minutes $m $seconds $s"
             }
             // CASE: format mm:ss
             false -> {
-                timeString = "$minutes $m $seconds $s"
+                "$minutes $m $seconds $s"
             }
         }
         return timeString
@@ -60,7 +60,7 @@ object DateTimeHelper {
 
     /* Create sortable string for date - used for filenames  */
     fun convertToSortableDateString(date: Date): String {
-        val dateFormat: SimpleDateFormat = SimpleDateFormat("yyyy-MM-dd-HH-mm-ss", Locale.US)
+        val dateFormat = SimpleDateFormat("yyyy-MM-dd-HH-mm-ss", Locale.US)
         return dateFormat.format(date)
     }
 
@@ -85,7 +85,7 @@ object DateTimeHelper {
 
     /* Calculates time difference between two locations */
     fun calculateTimeDistance(previousLocation: Location?, location: Location): Long {
-        var timeDifference: Long = 0L
+        var timeDifference = 0L
         // two data points needed to calculate time difference
         if (previousLocation != null) {
             // get time difference

app/src/main/java/org/y20k/trackbook/helpers/FileHelper.kt

@@ -35,6 +35,8 @@ import java.text.NumberFormat
 import java.util.*
 import kotlin.coroutines.resume
 import kotlin.coroutines.suspendCoroutine
+import kotlin.math.ln
+import kotlin.math.pow
 
 
 /*
@@ -61,14 +63,14 @@ object FileHelper {
     /* Get file size for given Uri */
     fun getFileSize(context: Context, uri: Uri): Long {
         val cursor: Cursor? = context.contentResolver.query(uri, null, null, null, null)
-        if (cursor != null) {
+        return if (cursor != null) {
             val sizeIndex: Int = cursor.getColumnIndex(OpenableColumns.SIZE)
             cursor.moveToFirst()
             val size: Long = cursor.getLong(sizeIndex)
             cursor.close()
-            return size
+            size
         } else {
-            return 0L
+            0L
         }
     }
 
@@ -76,14 +78,14 @@ object FileHelper {
     /* Get file name for given Uri */
     fun getFileName(context: Context, uri: Uri): String {
         val cursor: Cursor? = context.contentResolver.query(uri, null, null, null, null)
-        if (cursor != null) {
+        return if (cursor != null) {
             val nameIndex: Int = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME)
             cursor.moveToFirst()
             val name: String = cursor.getString(nameIndex)
             cursor.close()
-            return name
+            name
         } else {
-            return String()
+            String()
         }
     }
 
@@ -110,8 +112,8 @@ object FileHelper {
     fun readTracklist(context: Context): Tracklist {
         LogHelper.v(TAG, "Reading Tracklist - Thread: ${Thread.currentThread().name}")
         // get JSON from text file
-        val json: String = readTextFile(context, getTracklistFileUri(context))
+        val json: String = readTextFile(getTracklistFileUri(context))
-        var tracklist: Tracklist = Tracklist()
+        var tracklist = Tracklist()
         when (json.isNotBlank()) {
             // convert JSON and return as tracklist
             true -> try {
@@ -125,10 +127,10 @@ object FileHelper {
 
 
     /* Reads track from storage using GSON */
-    fun readTrack(context: Context, fileUri: Uri): Track {
+    fun readTrack(fileUri: Uri): Track {
         // get JSON from text file
-        val json: String = readTextFile(context, fileUri)
+        val json: String = readTextFile(fileUri)
-        var track: Track = Track()
+        var track = Track()
         when (json.isNotEmpty()) {
             // convert JSON and return as track
             true -> try {
@@ -305,7 +307,7 @@ object FileHelper {
         tracklist.modificationDate = modificationDate
         // convert to JSON
         val gson: Gson = getCustomGson()
-        var json: String = String()
+        var json = String()
         try {
             json = gson.toJson(tracklist)
         } catch (e: Exception) {
@@ -328,7 +330,7 @@ object FileHelper {
     private fun renameTrack(context: Context, track: Track, newName: String) {
         // search track in tracklist
         val tracklist: Tracklist = readTracklist(context)
-        var trackUriString: String = String()
+        var trackUriString = String()
         tracklist.tracklistElements.forEach { tracklistElement ->
             if (tracklistElement.getTrackId() == track.getTrackId()) {
                 // rename tracklist element
@@ -402,7 +404,7 @@ object FileHelper {
     /* Converts track to JSON */
     private fun getTrackJsonString(track: Track): String {
         val gson: Gson = getCustomGson()
-        var json: String = String()
+        var json = String()
         try {
             json = gson.toJson(track)
         } catch (e: Exception) {
@@ -432,13 +434,13 @@ object FileHelper {
         if (bytes < unit) return "$bytes B"
 
         // calculate exp
-        val exp: Int = (Math.log(bytes.toDouble()) / Math.log(unit.toDouble())).toInt()
+        val exp: Int = (ln(bytes.toDouble()) / ln(unit.toDouble())).toInt()
 
         // determine prefix symbol
         val prefix: String = ((if (si) "kMGTPE" else "KMGTPE")[exp - 1] + if (si) "" else "i")
 
         // calculate result and set number format
-        val result: Double = bytes / Math.pow(unit.toDouble(), exp.toDouble())
+        val result: Double = bytes / unit.toDouble().pow(exp.toDouble())
         val numberFormat = NumberFormat.getNumberInstance()
         numberFormat.maximumFractionDigits = 1
 
@@ -447,7 +449,7 @@ object FileHelper {
 
 
     /* Reads InputStream from file uri and returns it as String */
-    private fun readTextFile(context: Context, fileUri: Uri): String {
+    private fun readTextFile(fileUri: Uri): String {
         // todo read https://commonsware.com/blog/2016/03/15/how-consume-content-uri.html
         // https://developer.android.com/training/secure-file-sharing/retrieve-info
         val file: File = fileUri.toFile()
@@ -457,7 +459,7 @@ object FileHelper {
         }
         // read until last line reached
         val stream: InputStream = file.inputStream()
-        val reader: BufferedReader = BufferedReader(InputStreamReader(stream))
+        val reader = BufferedReader(InputStreamReader(stream))
         val builder: StringBuilder = StringBuilder()
         reader.forEachLine {
             builder.append(it)
@@ -477,7 +479,6 @@ object FileHelper {
 
     /* Writes given bitmap as image file to storage */
     private fun writeImageFile(
-        context: Context,
         bitmap: Bitmap,
         file: File,
         format: Bitmap.CompressFormat = Bitmap.CompressFormat.JPEG,

app/src/main/java/org/y20k/trackbook/helpers/LengthUnitHelper.kt

@@ -89,7 +89,7 @@ object LengthUnitHelper {
     /* Determines which unit system the device is using (metric or imperial) */
     fun useImperialUnits(): Boolean {
         // America (US), Liberia (LR), Myanmar(MM) use the imperial system
-        val imperialSystemCountries = Arrays.asList("US", "LR", "MM")
+        val imperialSystemCountries = listOf("US", "LR", "MM")
         val countryCode = Locale.getDefault().country
         return imperialSystemCountries.contains(countryCode)
     }
@@ -102,7 +102,7 @@ object LengthUnitHelper {
         trackLength: Float,
         useImperialUnits: Boolean = false
     ): String {
-        var speed: String = "0"
+        var speed = "0"
 
         // duration minus pause in seconds
         val duration: Long = (trackDuration - trackRecordingPause) / 1000L
@@ -117,21 +117,21 @@ object LengthUnitHelper {
             speed = bd.toPlainString()
         }
 
-        when (useImperialUnits) {
+        return when (useImperialUnits) {
-            true -> return "$speed mph"
+            true -> "$speed mph"
-            false -> return "$speed km/h"
+            false -> "$speed km/h"
         }
     }
 
 
     /* Coverts meters per second to either km/h or mph */
     fun convertMetersPerSecond(metersPerSecond: Float, useImperial: Boolean = false): Double {
-        if (useImperial) {
+        return if (useImperial) {
             // mph
-            return metersPerSecond * 2.2369362920544
+            metersPerSecond * 2.2369362920544
         } else {
             // km/h
-            return metersPerSecond * 3.6
+            metersPerSecond * 3.6
         }
     }
 

app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.kt

@@ -40,7 +40,7 @@ object LocationHelper {
 
     /* Get default location */
     fun getDefaultLocation(): Location {
-        val defaultLocation: Location = Location(LocationManager.NETWORK_PROVIDER)
+        val defaultLocation = Location(LocationManager.NETWORK_PROVIDER)
         defaultLocation.latitude = Keys.DEFAULT_LATITUDE
         defaultLocation.longitude = Keys.DEFAULT_LONGITUDE
         defaultLocation.accuracy = Keys.DEFAULT_ACCURACY
@@ -75,10 +75,11 @@ object LocationHelper {
             val lastKnownLocationNetwork: Location =
                 locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER)
                     ?: lastKnownLocation
-            when (isBetterLocation(lastKnownLocationGps, lastKnownLocationNetwork)) {
+            lastKnownLocation =
-                true -> lastKnownLocation = lastKnownLocationGps
+                when (isBetterLocation(lastKnownLocationGps, lastKnownLocationNetwork)) {
-                false -> lastKnownLocation = lastKnownLocationNetwork
+                    true -> lastKnownLocationGps
-            }
+                    false -> lastKnownLocationNetwork
+                }
         }
         return lastKnownLocation
     }
@@ -127,20 +128,20 @@ object LocationHelper {
 
     /* Checks if GPS location provider is available and enabled */
     fun isGpsEnabled(locationManager: LocationManager): Boolean {
-        if (locationManager.allProviders.contains(LocationManager.GPS_PROVIDER)) {
+        return if (locationManager.allProviders.contains(LocationManager.GPS_PROVIDER)) {
-            return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)
+            locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)
         } else {
-            return false
+            false
         }
     }
 
 
     /* Checks if Network location provider is available and enabled */
     fun isNetworkEnabled(locationManager: LocationManager): Boolean {
-        if (locationManager.allProviders.contains(LocationManager.NETWORK_PROVIDER)) {
+        return if (locationManager.allProviders.contains(LocationManager.NETWORK_PROVIDER)) {
-            return locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
+            locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
         } else {
-            return false
+            false
         }
     }
 
@@ -154,14 +155,10 @@ object LocationHelper {
 
     /* Checks if given location is accurate */
     fun isAccurateEnough(location: Location, locationAccuracyThreshold: Int): Boolean {
-        val isAccurate: Boolean
+        return when (location.provider) {
-        when (location.provider) {
+            LocationManager.GPS_PROVIDER -> location.accuracy < locationAccuracyThreshold
-            LocationManager.GPS_PROVIDER -> isAccurate =
+            else -> location.accuracy < locationAccuracyThreshold + 10 // a bit more relaxed when location comes from network provider
-                location.accuracy < locationAccuracyThreshold
-            else -> isAccurate =
-                location.accuracy < locationAccuracyThreshold + 10 // a bit more relaxed when location comes from network provider
         }
-        return isAccurate
     }
 
 
@@ -204,10 +201,10 @@ object LocationHelper {
         val distanceThreshold: Float
         val averageAccuracy: Float = (previousLocation.accuracy + location.accuracy) / 2
         // increase the distance threshold if one or both locations are
-        if (averageAccuracy > Keys.DEFAULT_THRESHOLD_DISTANCE) {
+        distanceThreshold = if (averageAccuracy > Keys.DEFAULT_THRESHOLD_DISTANCE) {
-            distanceThreshold = averageAccuracy
+            averageAccuracy
         } else {
-            distanceThreshold = Keys.DEFAULT_THRESHOLD_DISTANCE
+            Keys.DEFAULT_THRESHOLD_DISTANCE
         }
         // location is different when far enough away from previous location
         return calculateDistance(previousLocation, location) > distanceThreshold
@@ -216,7 +213,7 @@ object LocationHelper {
 
     /* Calculates distance in meters between two locations */
     fun calculateDistance(previousLocation: Location?, location: Location): Float {
-        var distance: Float = 0f
+        var distance = 0f
         // two data points needed to calculate distance
         if (previousLocation != null) {
             // add up distance

app/src/main/java/org/y20k/trackbook/helpers/LogHelper.kt

@@ -78,9 +78,9 @@ object LogHelper {
 
     private fun log(tag: String, level: Int, t: Throwable?, vararg messages: Any) {
         val message: String
-        if (t == null && messages.size == 1) {
+        message = if (t == null && messages.size == 1) {
             // handle this common case without the extra cost of creating a stringbuffer:
-            message = messages[0].toString()
+            messages[0].toString()
         } else {
             val sb = StringBuilder()
             for (m in messages) {
@@ -89,7 +89,7 @@ object LogHelper {
             if (t != null) {
                 sb.append("\n").append(Log.getStackTraceString(t))
             }
-            message = sb.toString()
+            sb.toString()
         }
         Log.println(level, tag, message)
 

app/src/main/java/org/y20k/trackbook/helpers/MapOverlay.kt

@@ -65,23 +65,25 @@ class MapOverlay(private var markerListener: MarkerListener) {
         when (trackingState) {
             // CASE: Tracking active
             Keys.STATE_TRACKING_ACTIVE -> {
-                when (locationIsOld) {
+                newMarker = when (locationIsOld) {
-                    true -> newMarker = ContextCompat.getDrawable(
+                    true -> ContextCompat.getDrawable(
                         context,
                         R.drawable.ic_marker_location_red_grey_24dp
                     )!!
-                    false -> newMarker =
+                    false -> ContextCompat.getDrawable(
-                        ContextCompat.getDrawable(context, R.drawable.ic_marker_location_red_24dp)!!
+                        context,
+                        R.drawable.ic_marker_location_red_24dp
+                    )!!
                 }
             }
             // CASE. Tracking is NOT active
             else -> {
-                when (locationIsOld) {
+                newMarker = when (locationIsOld) {
-                    true -> newMarker = ContextCompat.getDrawable(
+                    true -> ContextCompat.getDrawable(
                         context,
                         R.drawable.ic_marker_location_blue_grey_24dp
                     )!!
-                    false -> newMarker = ContextCompat.getDrawable(
+                    false -> ContextCompat.getDrawable(
                         context,
                         R.drawable.ic_marker_location_blue_24dp
                     )!!
@@ -124,36 +126,42 @@ class MapOverlay(private var markerListener: MarkerListener) {
             when (trackingState) {
                 // CASE: Recording is active
                 Keys.STATE_TRACKING_ACTIVE -> {
-                    if (wayPoint.starred) {
+                    newMarker = when {
-                        newMarker =
+                        wayPoint.starred -> {
                             ContextCompat.getDrawable(context, R.drawable.ic_star_red_24dp)!!
-                    } else if (wayPoint.isStopOver) {
+                        }
-                        newMarker = ContextCompat.getDrawable(
+                        wayPoint.isStopOver -> {
-                            context,
+                            ContextCompat.getDrawable(
-                            R.drawable.ic_marker_track_location_grey_24dp
+                                context,
-                        )!!
+                                R.drawable.ic_marker_track_location_grey_24dp
-                    } else {
+                            )!!
-                        newMarker = ContextCompat.getDrawable(
+                        }
-                            context,
+                        else -> {
-                            R.drawable.ic_marker_track_location_red_24dp
+                            ContextCompat.getDrawable(
-                        )!!
+                                context,
+                                R.drawable.ic_marker_track_location_red_24dp
+                            )!!
+                        }
                     }
                 }
                 // CASE: Recording is paused/stopped
                 else -> {
-                    if (wayPoint.starred) {
+                    newMarker = when {
-                        newMarker =
+                        wayPoint.starred -> {
                             ContextCompat.getDrawable(context, R.drawable.ic_star_blue_24dp)!!
-                    } else if (wayPoint.isStopOver) {
+                        }
-                        newMarker = ContextCompat.getDrawable(
+                        wayPoint.isStopOver -> {
-                            context,
+                            ContextCompat.getDrawable(
-                            R.drawable.ic_marker_track_location_grey_24dp
+                                context,
-                        )!!
+                                R.drawable.ic_marker_track_location_grey_24dp
-                    } else {
+                            )!!
-                        newMarker = ContextCompat.getDrawable(
+                        }
-                            context,
+                        else -> {
-                            R.drawable.ic_marker_track_location_blue_24dp
+                            ContextCompat.getDrawable(
-                        )!!
+                                context,
+                                R.drawable.ic_marker_track_location_blue_24dp
+                            )!!
+                        }
                     }
                 }
             }
@@ -185,13 +193,13 @@ class MapOverlay(private var markerListener: MarkerListener) {
         provider: String,
         time: Long
     ): OverlayItem {
-        val title: String =
+        val title =
             "${context.getString(R.string.marker_description_time)}: ${SimpleDateFormat.getTimeInstance(
                 SimpleDateFormat.MEDIUM,
                 Locale.getDefault()
             ).format(time)}"
         //val description: String = "${context.getString(R.string.marker_description_accuracy)}: ${DecimalFormat("#0.00").format(accuracy)} (${provider})"
-        val description: String =
+        val description =
             "${context.getString(R.string.marker_description_time)}: ${SimpleDateFormat.getTimeInstance(
                 SimpleDateFormat.MEDIUM,
                 Locale.getDefault()
@@ -199,7 +207,7 @@ class MapOverlay(private var markerListener: MarkerListener) {
                 .format(time)} | ${context.getString(R.string.marker_description_accuracy)}: ${DecimalFormat(
                 "#0.00"
             ).format(accuracy)} (${provider})"
-        val position: GeoPoint = GeoPoint(latitude, longitude)
+        val position = GeoPoint(latitude, longitude)
         return OverlayItem(title, description, position)
     }
 

app/src/main/java/org/y20k/trackbook/helpers/PreferencesHelper.kt

@@ -116,7 +116,7 @@ object PreferencesHelper {
             LocationManager.NETWORK_PROVIDER
         ) ?: LocationManager.NETWORK_PROVIDER
         // create location
-        val currentBestLocation: Location = Location(provider)
+        val currentBestLocation = Location(provider)
         // load location attributes
         currentBestLocation.latitude =
             settings.getDouble(Keys.PREF_CURRENT_BEST_LOCATION_LATITUDE, Keys.DEFAULT_LATITUDE)

app/src/main/java/org/y20k/trackbook/helpers/TrackHelper.kt

@@ -47,9 +47,8 @@ object TrackHelper {
         tracklistElement.date.time
 
 
-    /* Adds given locatiom as waypoint to track */
+    /* Adds given location as waypoint to track */
     fun addWayPointToTrack(
-        context: Context,
         track: Track,
         location: Location,
         locationAccuracyThreshold: Int,
@@ -151,10 +150,10 @@ object TrackHelper {
             // save number of satellites
             val numberOfSatellites: Int
             val extras = location.extras
-            if (extras != null && extras.containsKey("satellites")) {
+            numberOfSatellites = if (extras != null && extras.containsKey("satellites")) {
-                numberOfSatellites = extras.getInt("satellites", 0)
+                extras.getInt("satellites", 0)
             } else {
-                numberOfSatellites = 0
+                0
             }
 
             // add current location as point to center on for later display
@@ -187,10 +186,9 @@ object TrackHelper {
 
     /* Creates GPX string for given track */
     fun createGpxString(track: Track): String {
-        var gpxString: String
 
         // add header
-        gpxString = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?>\n" +
+        var gpxString: String = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?>\n" +
                 "<gpx version=\"1.1\" creator=\"Trackbook App (Android)\"\n" +
                 "     xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n" +
                 "     xsi:schemaLocation=\"http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd\">\n"

app/src/main/java/org/y20k/trackbook/helpers/UiHelper.kt

@@ -41,7 +41,7 @@ object UiHelper {
 
 
     /* Sets layout margins for given view in DP */
-    fun setViewMargins(
+    private fun setViewMargins(
         context: Context,
         view: View,
         left: Int = 0,

app/src/main/java/org/y20k/trackbook/tracklist/TracklistAdapter.kt

@@ -158,18 +158,17 @@ class TracklistAdapter(private val fragment: Fragment) :
     private fun createTrackDataString(position: Int): String {
         val tracklistElement: TracklistElement = tracklist.tracklistElements[position]
         val trackDataString: String
-        when (tracklistElement.name == tracklistElement.dateString) {
+        trackDataString = when (tracklistElement.name == tracklistElement.dateString) {
             // CASE: no individual name set - exclude date
-            true -> trackDataString = "${LengthUnitHelper.convertDistanceToString(
+            true -> "${LengthUnitHelper.convertDistanceToString(
                 tracklistElement.length,
                 useImperial
             )} • ${tracklistElement.durationString}"
             // CASE: no individual name set - include date
-            false -> trackDataString =
+            false -> "${tracklistElement.dateString} • ${LengthUnitHelper.convertDistanceToString(
-                "${tracklistElement.dateString} • ${LengthUnitHelper.convertDistanceToString(
+                tracklistElement.length,
-                    tracklistElement.length,
+                useImperial
-                    useImperial
+            )} • ${tracklistElement.durationString}"
-                )} • ${tracklistElement.durationString}"
         }
         return trackDataString
     }

app/src/main/java/org/y20k/trackbook/ui/MapFragmentLayoutHolder.kt

@@ -65,11 +65,11 @@ data class MapFragmentLayoutHolder(
 
 
     /* Main class variables */
-    val rootView: View
+    val rootView: View = inflater.inflate(R.layout.fragment_map, container, false)
-    val mapView: MapView
+    private val mapView: MapView
     val currentLocationButton: FloatingActionButton
     val recordingButton: FloatingActionButton
-    val recordingButtonSubMenu: Group
+    private val recordingButtonSubMenu: Group
     val saveButton: FloatingActionButton
     val clearButton: FloatingActionButton
     val resumeButton: FloatingActionButton
@@ -84,7 +84,6 @@ data class MapFragmentLayoutHolder(
     /* Init block */
     init {
         // find views
-        rootView = inflater.inflate(R.layout.fragment_map, container, false)
         mapView = rootView.findViewById(R.id.map)
         currentLocationButton = rootView.findViewById(R.id.fab_location_button)
         recordingButton = rootView.findViewById(R.id.fab_main_button)
@@ -139,7 +138,7 @@ data class MapFragmentLayoutHolder(
     /* Listen for user interaction */
     @SuppressLint("ClickableViewAccessibility")
     private fun addInteractionListener() {
-        mapView.setOnTouchListener { v, event ->
+        mapView.setOnTouchListener { _, _ ->
             userInteraction = true
             false
         }
@@ -160,7 +159,7 @@ data class MapFragmentLayoutHolder(
     /* Save current best location and state of map to shared preferences */
     fun saveState(currentBestLocation: Location) {
         PreferencesHelper.saveCurrentBestLocation(context, currentBestLocation)
-        PreferencesHelper.saveZoomLevel(context, mapView.getZoomLevelDouble())
+        PreferencesHelper.saveZoomLevel(context, mapView.zoomLevelDouble)
         // reset user interaction state
         userInteraction = false
     }

app/src/main/java/org/y20k/trackbook/ui/TrackFragmentLayoutHolder.kt

@@ -63,7 +63,7 @@ data class TrackFragmentLayoutHolder(
 
 
     /* Main class variables */
-    val rootView: View
+    val rootView: View = inflater.inflate(R.layout.fragment_track, container, false)
     val shareButton: ImageButton
     val deleteButton: ImageButton
     val editButton: ImageButton
@@ -96,7 +96,6 @@ data class TrackFragmentLayoutHolder(
     /* Init block */
     init {
         // find views
-        rootView = inflater.inflate(R.layout.fragment_track, container, false)
         mapView = rootView.findViewById(R.id.map)
         shareButton = rootView.findViewById(R.id.save_button)
         deleteButton = rootView.findViewById(R.id.delete_button)
@@ -202,10 +201,9 @@ data class TrackFragmentLayoutHolder(
     private fun setupStatisticsViews() {
 
         // get step count string
-        val steps: String
+        val steps: String =
-        if (track.stepCount == -1f) steps =
+            if (track.stepCount == -1f) context.getString(R.string.statistics_sheet_p_steps_no_pedometer)
-            context.getString(R.string.statistics_sheet_p_steps_no_pedometer)
+            else track.stepCount.roundToInt().toString()
-        else steps = track.stepCount.roundToInt().toString()
 
         // populate views
         trackNameView.text = track.name

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

@@ -13,7 +13,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:contentDescription="@string/descr_map_current_track"
-        android:visibility="visible"></org.osmdroid.views.MapView>
+        android:visibility="visible" />
 
     <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/container"

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

@@ -1,2 +1,2 @@
 <?xml version="1.0" encoding="utf-8"?>
-<resources></resources>
+<resources />