Implemented file logging settings

Implemented log rotation, log deletion
Minor fixes

ultrasonic/src/main/java/org/moire/ultrasonic/fragment/SettingsFragment.java

@@ -22,6 +22,7 @@ import org.moire.ultrasonic.featureflags.Feature;
 import org.moire.ultrasonic.featureflags.FeatureStorage;
 import org.moire.ultrasonic.filepicker.FilePickerDialog;
 import org.moire.ultrasonic.filepicker.OnFileSelectedListener;
+import org.moire.ultrasonic.log.FileLoggerTree;
 import org.moire.ultrasonic.provider.SearchSuggestionProvider;
 import org.moire.ultrasonic.service.Consumer;
 import org.moire.ultrasonic.service.MediaPlayerController;
@@ -70,6 +71,7 @@ public class SettingsFragment extends PreferenceFragment
     private PreferenceCategory serversCategory;
     private Preference resumeOnBluetoothDevice;
     private Preference pauseOnBluetoothDevice;
+    private CheckBoxPreference debugLogToFile;
 
     private SharedPreferences settings;
 
@@ -118,6 +120,7 @@ public class SettingsFragment extends PreferenceFragment
         serversCategory = (PreferenceCategory) findPreference(Constants.PREFERENCES_KEY_SERVERS_KEY);
         resumeOnBluetoothDevice = findPreference(Constants.PREFERENCES_KEY_RESUME_ON_BLUETOOTH_DEVICE);
         pauseOnBluetoothDevice = findPreference(Constants.PREFERENCES_KEY_PAUSE_ON_BLUETOOTH_DEVICE);
+        debugLogToFile = (CheckBoxPreference) findPreference(Constants.PREFERENCES_KEY_DEBUG_LOG_TO_FILE);
 
         sharingDefaultGreeting.setText(Util.getShareGreeting(getActivity()));
         setupClearSearchPreference();
@@ -171,6 +174,8 @@ public class SettingsFragment extends PreferenceFragment
             setBluetoothPreferences(sharedPreferences.getBoolean(key, true));
         } else if (Constants.PREFERENCES_KEY_IMAGE_LOADER_CONCURRENCY.equals(key)) {
             setImageLoaderConcurrency(Integer.parseInt(sharedPreferences.getString(key, "5")));
+        } else if (Constants.PREFERENCES_KEY_DEBUG_LOG_TO_FILE.equals(key)) {
+            setDebugLogToFile(sharedPreferences.getBoolean(key, false));
         }
     }
 
@@ -415,6 +420,13 @@ public class SettingsFragment extends PreferenceFragment
             sendBluetoothAlbumArt.setChecked(false);
             sendBluetoothAlbumArt.setEnabled(false);
         }
+
+        if (debugLogToFile.isChecked()) {
+            debugLogToFile.setSummary(getString(R.string.settings_debug_log_path,
+                FileUtil.getUltrasonicDirectory(getActivity()), FileLoggerTree.FILENAME));
+        } else {
+            debugLogToFile.setSummary("");
+        }
     }
 
     private static void setImageLoaderConcurrency(int concurrency) {
@@ -482,4 +494,47 @@ public class SettingsFragment extends PreferenceFragment
         // Clear download queue.
         mediaPlayerControllerLazy.getValue().clear();
     }
+
+    private void setDebugLogToFile(boolean writeLog) {
+        if (writeLog) {
+            FileLoggerTree.Companion.plantToTimberForest(getActivity().getApplicationContext());
+            Timber.i("Enabled debug logging to file");
+        } else {
+            FileLoggerTree.Companion.uprootFromTimberForest();
+            Timber.i("Disabled debug logging to file");
+
+            int fileNum = FileLoggerTree.Companion.getLogFileNumber(getActivity());
+            long fileSize = FileLoggerTree.Companion.getLogFileSizes(getActivity());
+            String message = getString(R.string.settings_debug_log_summary,
+                String.valueOf(fileNum),
+                String.valueOf(Math.ceil(fileSize / 1000000d)),
+                FileUtil.getUltrasonicDirectory(getActivity()));
+
+            new AlertDialog.Builder(getActivity())
+                .setMessage(message)
+                .setIcon(android.R.drawable.ic_dialog_info)
+                .setNegativeButton(R.string.settings_debug_log_keep, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialogInterface, int i) {
+                        dialogInterface.cancel();
+                    }
+                })
+                .setPositiveButton(R.string.settings_debug_log_delete, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialogInterface, int i) {
+                        FileLoggerTree.Companion.deleteLogFiles(getActivity());
+                        Timber.i("Deleted debug log files");
+                        dialogInterface.dismiss();
+                        new AlertDialog.Builder(getActivity()).setMessage(R.string.settings_debug_log_deleted)
+                            .setPositiveButton(R.string.common_ok, new DialogInterface.OnClickListener() {
+                                @Override
+                                public void onClick(DialogInterface dialogInterface, int i) {
+                                    dialogInterface.dismiss();
+                                }
+                            }).create().show();
+                    }
+                })
+                .create().show();
+        }
+    }
 }

ultrasonic/src/main/java/org/moire/ultrasonic/util/Constants.java

@@ -134,6 +134,7 @@ public final class Constants
 	public static final String PREFERENCES_KEY_FIRST_RUN_EXECUTED = "firstRunExecuted";
 	public static final String PREFERENCES_KEY_RESUME_ON_BLUETOOTH_DEVICE = "resumeOnBluetoothDevice";
 	public static final String PREFERENCES_KEY_PAUSE_ON_BLUETOOTH_DEVICE = "pauseOnBluetoothDevice";
+	public static final String PREFERENCES_KEY_DEBUG_LOG_TO_FILE = "debugLogToFile";
 
 	public static final int PREFERENCE_VALUE_ALL = 0;
 	public static final int PREFERENCE_VALUE_A2DP = 1;

ultrasonic/src/main/java/org/moire/ultrasonic/util/Util.java

@@ -1457,4 +1457,11 @@ public class Util
 		SharedPreferences preferences = getPreferences(context);
 		return preferences.getInt(Constants.PREFERENCES_KEY_PAUSE_ON_BLUETOOTH_DEVICE, Constants.PREFERENCE_VALUE_A2DP);
 	}
+
+	public static boolean getDebugLogToFile(Context context)
+	{
+		SharedPreferences preferences = getPreferences(context);
+		return preferences.getBoolean(Constants.PREFERENCES_KEY_DEBUG_LOG_TO_FILE, false);
+	}
+
 }

ultrasonic/src/main/kotlin/org/moire/ultrasonic/app/UApp.kt

@@ -2,7 +2,6 @@ package org.moire.ultrasonic.app
 
 import androidx.multidex.MultiDexApplication
 import org.koin.android.ext.koin.androidContext
-import org.koin.android.ext.koin.androidLogger
 import org.koin.core.context.startKoin
 import org.koin.core.logger.Level
 import org.moire.ultrasonic.BuildConfig
@@ -13,8 +12,8 @@ import org.moire.ultrasonic.di.featureFlagsModule
 import org.moire.ultrasonic.di.mediaPlayerModule
 import org.moire.ultrasonic.di.musicServiceModule
 import org.moire.ultrasonic.log.FileLoggerTree
-import org.moire.ultrasonic.log.TimberKoinLogger
 import org.moire.ultrasonic.log.timberLogger
+import org.moire.ultrasonic.util.Util
 import timber.log.Timber
 import timber.log.Timber.DebugTree
 
@@ -24,7 +23,9 @@ class UApp : MultiDexApplication() {
 
         if (BuildConfig.DEBUG) {
             Timber.plant(DebugTree())
-            Timber.plant(FileLoggerTree(this))
+        }
+        if (Util.getDebugLogToFile(this)) {
+            FileLoggerTree.plantToTimberForest(this)
         }
 
         startKoin {

ultrasonic/src/main/kotlin/org/moire/ultrasonic/di/MusicServiceModule.kt

@@ -1,8 +1,8 @@
 @file:JvmName("MusicServiceModule")
 package org.moire.ultrasonic.di
 
-import okhttp3.logging.HttpLoggingInterceptor
 import kotlin.math.abs
+import okhttp3.logging.HttpLoggingInterceptor
 import org.koin.android.ext.koin.androidContext
 import org.koin.core.qualifier.named
 import org.koin.dsl.module

ultrasonic/src/main/kotlin/org/moire/ultrasonic/log/FileLoggerTree.kt

@@ -1,37 +1,106 @@
 package org.moire.ultrasonic.log
 
 import android.content.Context
+import java.io.File
+import java.io.FileWriter
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
 import org.moire.ultrasonic.util.FileUtil
 import org.moire.ultrasonic.util.Util
 import timber.log.Timber
-import java.io.File
-import java.io.FileWriter
 
 /**
  * A Timber Tree which can be used to log to a file
  * Subclass of the DebugTree so it inherits the Tag handling
  */
 class FileLoggerTree(val context: Context) : Timber.DebugTree() {
-    private val filename = "ultrasonic.log"
+    private val dateFormat = SimpleDateFormat("HH:mm:ss.SSS", Locale.getDefault())
 
+    /**
+     * Writes a log entry to file
+     */
     override fun log(priority: Int, tag: String?, message: String, t: Throwable?) {
-        var file: File? = null
         var writer: FileWriter? = null
+        callNum++
         try {
-            file = File(FileUtil.getUltrasonicDirectory(context), filename)
+            getNextLogFile()
             writer = FileWriter(file, true)
-            val exceptionString = t?.toString() ?: "";
-            writer.write("${logLevelToString(priority)} $tag $message $exceptionString\n")
-            writer.flush()
+            val exceptionString = t?.toString() ?: ""
+            val time: String = dateFormat.format(Date())
+            synchronized(file!!) {
+                writer.write(
+                    "$time: ${logLevelToString(priority)} $tag $message $exceptionString\n"
+                )
+                writer.flush()
+            }
         } catch (x: Throwable) {
-            super.e(x, "Failed to write log to %s", file)
+            // Using base class DebugTree here, we don't want to try to log this into file
+            super.log(6, TAG, String.format("Failed to write log to %s", file), x)
         } finally {
             if (writer != null) Util.close(writer)
         }
     }
 
-    private fun logLevelToString(logLevel: Int) : String {
-        return when(logLevel) {
+    /**
+     * Sets the file to log into
+     * This function also rotates the log files periodically, when they reach the predefined size
+     */
+    private fun getNextLogFile() {
+        if (file == null) {
+            synchronized(this) {
+                if (file != null) return
+                getNumberedFile(false)
+                // Using base class DebugTree here, we don't want to try to log this into file
+                super.log(4, TAG,String.format("Logging into file %s", file?.name), null)
+                return
+            }
+        }
+        if (callNum % 100 == 0) {
+            // Gain some performance by only executing this rarely
+            if (file!!.length() > MAX_LOGFILE_LENGTH) {
+                synchronized(this) {
+                    if (file!!.length() <= MAX_LOGFILE_LENGTH) return
+                    getNumberedFile(true)
+                    // Using base class DebugTree here, we don't want to try to log this into file
+                    super.log(
+                        4,
+                        TAG,
+                        String.format("Log file rotated, logging into file %s", file?.name),
+                        null
+                    )
+                }
+            }
+        }
+    }
+
+    /**
+     * Checks the number of log files
+     * @param next: if false, sets the current log file with the greatest number
+     * if true, sets a new file for logging with the next number
+     */
+    private fun getNumberedFile(next: Boolean) {
+        var fileNum = 1
+        val fileList = getLogFileList(context)
+
+        if (!fileList.isNullOrEmpty()) {
+            fileList.sortByDescending { t -> t.name }
+            val lastFile = fileList[0]
+            val number = fileNumberRegex.find(lastFile.name)?.groups?.get(1)?.value
+            if (number != null) {
+                fileNum = number.toInt()
+            }
+        }
+
+        if (next) fileNum++
+        file = File(
+            FileUtil.getUltrasonicDirectory(context),
+            FILENAME.replace("*", fileNum.toString())
+        )
+    }
+
+    private fun logLevelToString(logLevel: Int): String {
+        return when (logLevel) {
             2 -> "V"
             3 -> "D"
             4 -> "I"
@@ -41,4 +110,60 @@ class FileLoggerTree(val context: Context) : Timber.DebugTree() {
             else -> "U"
         }
     }
-}
+
+    companion object {
+        val TAG = FileLoggerTree::class.simpleName
+        @Volatile private var file: File? = null
+        const val FILENAME = "ultrasonic.*.log"
+        private val fileNameRegex = Regex(
+            FILENAME.replace(".", "\\.").replace("*", "\\d*")
+        )
+        private val fileNumberRegex = Regex(
+            FILENAME.replace(".", "\\.").replace("*", "(\\d*)")
+        )
+        const val MAX_LOGFILE_LENGTH = 10000000
+        var callNum = 0
+
+        fun plantToTimberForest(context: Context) {
+            if (!Timber.forest().any { t -> t is FileLoggerTree }) {
+                Timber.plant(FileLoggerTree(context))
+            }
+        }
+
+        fun uprootFromTimberForest() {
+            val fileLoggerTree = Timber.forest().singleOrNull { t -> t is FileLoggerTree }
+                ?: return
+            Timber.uproot(fileLoggerTree)
+            file = null
+        }
+
+        fun getLogFileNumber(context: Context): Int {
+            val fileList = getLogFileList(context)
+            if (!fileList.isNullOrEmpty()) return fileList.size
+            return 0
+        }
+
+        fun getLogFileSizes(context: Context): Long {
+            var sizeSum: Long = 0
+            val fileList = getLogFileList(context)
+            if (fileList.isNullOrEmpty()) return sizeSum
+            for (file in fileList) {
+                sizeSum += file.length()
+            }
+            return sizeSum
+        }
+
+        fun deleteLogFiles(context: Context) {
+            val fileList = getLogFileList(context)
+            if (fileList.isNullOrEmpty()) return
+            for (file in fileList) {
+                file.delete()
+            }
+        }
+
+        private fun getLogFileList(context: Context): Array<File> {
+            val directory = FileUtil.getUltrasonicDirectory(context)
+            return directory.listFiles { t -> t.name.matches(fileNameRegex) }
+        }
+    }
+}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/log/TimberKoinLogger.kt

@@ -19,7 +19,7 @@ fun KoinApplication.timberLogger(
 /**
  * Timber Logger implementation for Koin
  */
-class TimberKoinLogger (level: Level = Level.INFO) : Logger(level) {
+class TimberKoinLogger(level: Level = Level.INFO) : Logger(level) {
 
     override fun log(level: Level, msg: MESSAGE) {
         if (this.level <= level) {

ultrasonic/src/main/kotlin/org/moire/ultrasonic/log/TimberOkHttpLogger.kt

@@ -10,4 +10,4 @@ class TimberOkHttpLogger : HttpLoggingInterceptor.Logger {
     override fun log(message: String) {
         Timber.d(message)
     }
-}
+}

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

@@ -401,6 +401,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/values-es/strings.xml

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">Todos los dispositivos Bluetooth</string>
     <string name="settings.playback.bluetooth_a2dp">Solo dispositivos de audio (A2DP)</string>
     <string name="settings.playback.bluetooth_disabled">Deshabilitado</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic no puede acceder a la caché de los ficheros de música. La ubicación de la caché se restableció a la ruta predeterminada.</string>
     <string name="permissions.message_box_title">Atención</string>

ultrasonic/src/main/res/values-fr/strings.xml

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/values-hu/strings.xml

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">Minden Bluetooth eszköz</string>
     <string name="settings.playback.bluetooth_a2dp">Csak audio (A2DP) eszközök</string>
     <string name="settings.playback.bluetooth_disabled">Kikapcsolva</string>
+    <string name="settings.debug.title">Hibakeresési lehetőségek</string>
+    <string name="settings.debug.log_to_file">Hibakeresési napló írása fájlba</string>
+    <string name="settings.debug.log_path">A naplófájlok elérhetőek a következő helyen: %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">%1$s napló fájl ~%2$s MB méretben található a %3$s könyvtárban. Meg szeretnéd atrtani ezeket?</string>
+    <string name="settings.debug.log_keep">Fájlok megtartása</string>
+    <string name="settings.debug.log_delete">Fájlok törlése</string>
+    <string name="settings.debug.log_deleted">Naplófájlok törölve.</string>
 
     <string name="permissions.access_error">Az Ultrasonic nem éri el a zenei fájl gyorsítótárat. A gyorsítótár helye visszaállítva az alapbeállításra.</string>
     <string name="permissions.message_box_title">Figyelem</string>

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

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/values-pl/strings.xml

@@ -402,6 +402,13 @@ ponieważ api Subsonic nie wspiera nowego sposobu autoryzacji dla użytkowników
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/values-pt-rBR/strings.xml

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/values-pt/strings.xml

@@ -402,6 +402,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

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

@@ -405,6 +405,13 @@
     <string name="settings.playback.bluetooth_all">All Bluetooth devices</string>
     <string name="settings.playback.bluetooth_a2dp">Only audio (A2DP) devices</string>
     <string name="settings.playback.bluetooth_disabled">Disabled</string>
+    <string name="settings.debug.title">Debug options</string>
+    <string name="settings.debug.log_to_file">Write debug log to file</string>
+    <string name="settings.debug.log_path">The log files are available at %1$s/%2$s</string>
+    <string name="settings.debug.log_summary">There are %1$s log files taking up ~%2$s MB space in the %3$s directory. Do you want to keep these?</string>
+    <string name="settings.debug.log_keep">Keep files</string>
+    <string name="settings.debug.log_delete">Delete files</string>
+    <string name="settings.debug.log_deleted">Deleted log files.</string>
 
     <string name="permissions.access_error">Ultrasonic can\'t access the music file cache. Cache location was reset to the default path.</string>
     <string name="permissions.message_box_title">Warning</string>

ultrasonic/src/main/res/xml/settings.xml

@@ -305,7 +305,14 @@
             a:title="@string/feature_flags_five_star_rating_title"
             a:summary="@string/feature_flags_five_star_rating_description"
             />
-
+    </PreferenceCategory>
+    <PreferenceCategory a:title="@string/settings.debug.title">
+        <CheckBoxPreference
+            a:defaultValue="false"
+            a:key="debugLogToFile"
+            a:title="@string/settings.debug.log_to_file"
+            a:summary=""
+            />
     </PreferenceCategory>
 
 </PreferenceScreen>