Automatic language IDs (#196)

* Language IDs are now automatically generated. No more manual housekeeping.

* The database words are properly migrated to avoid dictionary re-import, because of the new IDs

* No unnecessary notifications when 'change language' key is pressed, but there is only one language

* Database code cleanup
	
	* Moved the database exceptions and room classes to separate packages

	* Migrations done the right way

* Updated the contribution guide

CONTRIBUTING.md

@@ -50,13 +50,17 @@ To support a new language one needs to:
     - Create a proper icon for each screen size. The icon needs to contain the abbreviation of the language. (e.g. "En" for "English").
     - The font must be Roboto Lt at an adequate size to fit the icon square with minimum padding.
     - The text must be white and the background must be transparent as per the [official Android guide](https://android-doc.github.io/guide/practices/ui_guidelines/icon_design_status_bar.html).
-    - To simplify the process, you could use Android Studio. It has a built-in icon generator accessible by right-cicking on "drawable" folder -> New -> Image Asset. Then choose "Icon Type": "Notification Icons", "Asset Type": Text, "Trim": No, "Padding": 0%.
+    - To simplify the process, you could use Android Studio. It has a built-in icon generator accessible by right-clicking on "drawable" folder -> New -> Image Asset. Then choose "Icon Type": "Notification Icons", "Asset Type": Text, "Trim": No, "Padding": 0%.
-- Find a suitable dictionary and add it to `assets` folder. Two file formats are supported, [see below](#dictionary-formats).
+- Find a suitable dictionary and add it to `assets/` folder. Two file formats are supported, [see below](#dictionary-formats).
 - Do not forget to include the dictionary license (or readme) file in the `docs/` folder.
-- Create a new language class in `languages/definitions/`. Make sure to set all properties.
+- Create a new language class in `languages/definitions/` and define its properties.
-  - `ID` must be the next available number.
+  - `name` is the native name of the language (e.g. "English", "Deutsch", "Українська").
-  - Set `isPunctuationPartOfWords` to `true`, if you need to use the 1-key for typing words, such as: `it's`, `a'tje` or `п'ят`. Otherwise, it would not be possible to type them, nor will they appear as suggestions. `false` will allow faster typing when apostrophes or other punctuation are not part of the words.
+  - `locale` contains the language and the country codes (e.g. "en-US", "es-AR", "it-IT"). Refer to the list of [supported locales in Java](https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#util-text).
-- Add the new language to the list in `LanguageCollection.java`. You only need to add it in one place, in the constructor. Please, be nice and maintain the alphabetical order.
+  - `dictionaryFile` is the name of the dictionary in `assets/` folder.
+  - `icon`, `abcLowerCaseIcon` and `abcUpperCaseIcon` are the respective status icons for Predictive mode, ABC (lowercase) and ABC (uppercase).
+  - Set `isPunctuationPartOfWords` to `true`, if the dictionary contains words with apostrophes or dashes, such as: `it's`, `you'll`, `a'tje` or `п'ят`. This will allow using 1-key for typing them (they will appear as suggestions). `false` will enable faster typing when apostrophes or other punctuation are not part of the words (no such words will be suggested).
+  - `characterMap` contains the letters and punctuation marks associated with each key.
+- Finally, add the new language to the list in `LanguageCollection.java`. You only need to add it in one place, in the constructor. Please, be nice and maintain the alphabetical order.
 
 
 ### Dictionary Formats
@@ -67,7 +71,7 @@ The most basic format is just a list of words where each word is on a new line.
 Constraints:
 - No single lowercase letters. The application will add them automatically.
 - No repeating words.
-- No digits or garbadge characters as part of the words.
+- No digits or garbage characters as part of the words.
 
 _The constraints will be verified automatically upon building._
 
@@ -108,8 +112,7 @@ Alternatively, if you don't have Android Studio, you could just use `res/values/
 ## Adding Support for Keys
 TT9 allows assigning hotkeys for performing different functions. If your phone has a special key that does not appear on the Hotkey configuration screen, you can easily add support for it.
 
-- Find [preferences/helpers/Hotkeys.java](io/github/sspanak/tt9/preferences/helpers/Hotkeys.java).
+- In `preferences/helpers/Hotkeys.java`, find the `generateList()` function.
-- In the file, find the `generateList()` function.
 - Add the new key there. The order of adding is used when displaying the dropdown options.
 - Optionally, you can translate the name of the key in different languages in the `res/values-XX/strings.xml` files.
 

src/io/github/sspanak/tt9/db/DictionaryDb.java

@@ -6,38 +6,26 @@ import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
 
-import androidx.annotation.NonNull;
-import androidx.room.Room;
-import androidx.room.RoomDatabase;
-import androidx.sqlite.db.SupportSQLiteDatabase;
-
 import java.util.ArrayList;
 import java.util.List;
 
 import io.github.sspanak.tt9.Logger;
+import io.github.sspanak.tt9.db.exceptions.InsertBlankWordException;
+import io.github.sspanak.tt9.db.room.TT9Room;
+import io.github.sspanak.tt9.db.room.Word;
 import io.github.sspanak.tt9.ime.TraditionalT9;
 import io.github.sspanak.tt9.languages.InvalidLanguageException;
 import io.github.sspanak.tt9.languages.Language;
 import io.github.sspanak.tt9.preferences.SettingsStore;
 
 public class DictionaryDb {
-	private static T9RoomDb dbInstance;
+	private static TT9Room dbInstance;
-
-	private static final RoomDatabase.Callback DROP_NORMALIZATION_TRIGGER = new RoomDatabase.Callback() {
-		@Override
-		public void onOpen(@NonNull SupportSQLiteDatabase db) {
-			super.onOpen(db);
-			db.execSQL("DROP TRIGGER IF EXISTS normalize_freq");
-		}
-	};
 
 
 	public static synchronized void init(Context context) {
 		if (dbInstance == null) {
 			context = context == null ? TraditionalT9.getMainContext() : context;
-			dbInstance = Room.databaseBuilder(context, T9RoomDb.class, "t9dict.db")
+			dbInstance = TT9Room.getInstance(context);
-				.addCallback(DROP_NORMALIZATION_TRIGGER) // @todo: Remove trigger dropping after December 2023. Assuming everyone would have upgraded by then.
-				.build();
 		}
 	}
 
@@ -47,7 +35,7 @@ public class DictionaryDb {
 	}
 
 
-	private static T9RoomDb getInstance() {
+	private static TT9Room getInstance() {
 		init();
 		return dbInstance;
 	}

src/io/github/sspanak/tt9/db/DictionaryLoader.java

@@ -11,9 +11,12 @@ import java.io.InputStreamReader;
 import java.io.LineNumberReader;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
-import java.util.regex.Pattern;
 
 import io.github.sspanak.tt9.Logger;
+import io.github.sspanak.tt9.db.exceptions.DictionaryImportAbortedException;
+import io.github.sspanak.tt9.db.exceptions.DictionaryImportAlreadyRunningException;
+import io.github.sspanak.tt9.db.exceptions.DictionaryImportException;
+import io.github.sspanak.tt9.db.room.Word;
 import io.github.sspanak.tt9.languages.InvalidLanguageCharactersException;
 import io.github.sspanak.tt9.languages.InvalidLanguageException;
 import io.github.sspanak.tt9.languages.Language;

src/io/github/sspanak/tt9/db/T9RoomDb.java

@@ -1,9 +0,0 @@
-package io.github.sspanak.tt9.db;
-
-import androidx.room.Database;
-import androidx.room.RoomDatabase;
-
-@Database(version = 5, entities = Word.class, exportSchema = false)
-abstract class T9RoomDb extends RoomDatabase {
-	public abstract WordsDao wordsDao();
-}

src/io/github/sspanak/tt9/db/exceptions/DictionaryImportAbortedException.java

@@ -1,4 +1,4 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.exceptions;
 
 public class DictionaryImportAbortedException extends Exception{
 	public DictionaryImportAbortedException() {

src/io/github/sspanak/tt9/db/exceptions/DictionaryImportAlreadyRunningException.java

@@ -1,4 +1,4 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.exceptions;
 
 public class DictionaryImportAlreadyRunningException extends Exception{
 	public DictionaryImportAlreadyRunningException() {

src/io/github/sspanak/tt9/db/exceptions/DictionaryImportException.java

@@ -1,11 +1,11 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.exceptions;
 
 public class DictionaryImportException extends Exception {
 	public final String file;
 	public final String word;
 	public final long line;
 
-	DictionaryImportException(String file, String word, long line) {
+	public DictionaryImportException(String file, String word, long line) {
 		super("Dictionary import failed");
 		this.file = file;
 		this.word = word;

src/io/github/sspanak/tt9/db/exceptions/InsertBlankWordException.java

@@ -1,7 +1,7 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.exceptions;
 
 public class InsertBlankWordException extends Exception {
-	protected InsertBlankWordException() {
+	public InsertBlankWordException() {
 		super("Cannot insert a blank word.");
 	}
 }

src/io/github/sspanak/tt9/db/migrations/DB6.java

@@ -0,0 +1,13 @@
+package io.github.sspanak.tt9.db.migrations;
+
+import androidx.room.migration.Migration;
+import androidx.sqlite.db.SupportSQLiteDatabase;
+
+public class DB6 {
+	public static final Migration MIGRATION = new Migration(5, 6) {
+		@Override
+		public void migrate(SupportSQLiteDatabase database) {
+			database.execSQL("DROP TRIGGER IF EXISTS normalize_freq");
+		}
+	};
+}

src/io/github/sspanak/tt9/db/migrations/DB7.java

@@ -0,0 +1,82 @@
+package io.github.sspanak.tt9.db.migrations;
+
+import android.content.Context;
+
+import androidx.room.migration.Migration;
+import androidx.sqlite.db.SupportSQLiteDatabase;
+
+import java.util.ArrayList;
+
+import io.github.sspanak.tt9.languages.definitions.Bulgarian;
+import io.github.sspanak.tt9.languages.definitions.Dutch;
+import io.github.sspanak.tt9.languages.definitions.English;
+import io.github.sspanak.tt9.languages.definitions.French;
+import io.github.sspanak.tt9.languages.definitions.German;
+import io.github.sspanak.tt9.languages.definitions.Italian;
+import io.github.sspanak.tt9.languages.definitions.Russian;
+import io.github.sspanak.tt9.languages.definitions.Spanish;
+import io.github.sspanak.tt9.languages.definitions.Ukrainian;
+import io.github.sspanak.tt9.preferences.SettingsStore;
+
+public class DB7 {
+	private Context ctx;
+
+	public Migration getMigration(Context context) {
+		ctx = context;
+		return migration;
+	}
+
+	private int getNewLanguageId(int oldId) {
+		switch (oldId) {
+			default:
+				return oldId;
+			case 1:
+				return new English().getId();
+			case 2:
+				return new Russian().getId();
+			case 3:
+				return new German().getId();
+			case 4:
+				return new French().getId();
+			case 5:
+				return new Italian().getId();
+			case 6:
+				return new Ukrainian().getId();
+			case 7:
+				return new Bulgarian().getId();
+			case 8:
+				return new Dutch().getId();
+			case 9:
+				return new Spanish().getId();
+		}
+	}
+
+	private final Migration migration = new Migration(6, 7) {
+		private void migrateSQL(SupportSQLiteDatabase database) {
+			for (int oldLangId = 1; oldLangId <= 9; oldLangId++) {
+				database.execSQL(
+					"UPDATE words " +
+					" SET lang = " + getNewLanguageId(oldLangId) +
+					" WHERE lang = " + oldLangId
+				);
+			}
+		}
+
+		private void migrateSettings() {
+			SettingsStore settings = new SettingsStore(ctx);
+
+			ArrayList<Integer> newLangIds = new ArrayList<>();
+			for (int langId : settings.getEnabledLanguageIds()) {
+				newLangIds.add(getNewLanguageId(langId));
+			}
+
+			settings.saveEnabledLanguageIds(newLangIds);
+		}
+
+		@Override
+		public void migrate(SupportSQLiteDatabase database) {
+			migrateSQL(database);
+			migrateSettings();
+		}
+	};
+}

src/io/github/sspanak/tt9/db/room/TT9Room.java

@@ -0,0 +1,22 @@
+package io.github.sspanak.tt9.db.room;
+
+import android.content.Context;
+
+import androidx.room.Database;
+import androidx.room.Room;
+import androidx.room.RoomDatabase;
+
+import io.github.sspanak.tt9.db.migrations.DB6;
+import io.github.sspanak.tt9.db.migrations.DB7;
+
+@Database(version = 7, entities = Word.class, exportSchema = false)
+public abstract class TT9Room extends RoomDatabase {
+	public abstract WordsDao wordsDao();
+
+	public static synchronized TT9Room getInstance(Context context) {
+		return Room
+			.databaseBuilder(context, TT9Room.class, "t9dict.db")
+			.addMigrations(DB6.MIGRATION, new DB7().getMigration(context))
+			.build();
+	}
+}

src/io/github/sspanak/tt9/db/room/Word.java

@@ -1,4 +1,4 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.room;
 
 import androidx.room.ColumnInfo;
 import androidx.room.Entity;

src/io/github/sspanak/tt9/db/room/WordsDao.java

@@ -1,4 +1,4 @@
-package io.github.sspanak.tt9.db;
+package io.github.sspanak.tt9.db.room;
 
 import androidx.room.Dao;
 import androidx.room.Insert;
@@ -9,12 +9,12 @@ import java.util.ArrayList;
 import java.util.List;
 
 @Dao
-interface WordsDao {
+public interface WordsDao {
 	@Query("SELECT COUNT(id) FROM words WHERE :langId < 0 OR lang = :langId")
 	int count(int langId);
 
 	@Query("DELETE FROM words WHERE LANG IN(:langIds)")
-	int deleteByLanguage(ArrayList<Integer> langIds);
+	void deleteByLanguage(ArrayList<Integer> langIds);
 
 	@Query("SELECT COUNT(id) FROM words WHERE lang = :langId AND word = :word")
 	int doesWordExist(int langId, String word);

src/io/github/sspanak/tt9/ime/TraditionalT9.java

@@ -63,7 +63,7 @@ public class TraditionalT9 extends KeyPadHandler {
 
 
 	private void validateFunctionKeys() {
-		if (!settings.areFunctionKeysSet()) {
+		if (settings.isSettingsKeyMissing()) {
 			settings.setDefaultKeys();
 		}
 	}
@@ -531,10 +531,15 @@ public class TraditionalT9 extends KeyPadHandler {
 			return false;
 		}
 
+		// when only one language is enabled, just acknowledge the key was pressed
+		if (mEnabledLanguages.size() < 2) {
+			return true;
+		}
+
 		// select the next language
-		int previousLangId = mEnabledLanguages.indexOf(mLanguage.getId());
+		int previous = mEnabledLanguages.indexOf(mLanguage.getId());
-		int nextLangId = previousLangId == -1 ? 0 : (previousLangId + 1) % mEnabledLanguages.size();
+		int next = (previous + 1) % mEnabledLanguages.size();
-		mLanguage = LanguageCollection.getLanguage(mEnabledLanguages.get(nextLangId));
+		mLanguage = LanguageCollection.getLanguage(mEnabledLanguages.get(next));
 
 		validateLanguages();
 

src/io/github/sspanak/tt9/ime/helpers/InputModeValidator.java

@@ -6,7 +6,6 @@ import io.github.sspanak.tt9.Logger;
 import io.github.sspanak.tt9.ime.modes.InputMode;
 import io.github.sspanak.tt9.languages.Language;
 import io.github.sspanak.tt9.languages.LanguageCollection;
-import io.github.sspanak.tt9.languages.definitions.English;
 import io.github.sspanak.tt9.preferences.SettingsStore;
 
 public class InputModeValidator {
@@ -17,7 +16,7 @@ public class InputModeValidator {
 			validLanguageIds.add(lang.getId());
 		}
 		if (validLanguageIds.size() == 0) {
-			validLanguageIds.add(1);
+			validLanguageIds.add(LanguageCollection.getDefault().getId());
 			Logger.e("tt9/validateEnabledLanguages", "The language list seems to be corrupted. Resetting to first language only.");
 		}
 
@@ -34,8 +33,7 @@ public class InputModeValidator {
 		String error = language != null ? "Language: " + language.getId() + " is not enabled." : "Invalid language.";
 
 		Language validLanguage = LanguageCollection.getLanguage(validLanguageIds.get(0));
-		validLanguage = validLanguage == null ? LanguageCollection.getLanguage(1) : validLanguage;
+		validLanguage = validLanguage != null ? validLanguage : LanguageCollection.getDefault();
-		validLanguage = validLanguage == null ? new English() : validLanguage;
 		settings.saveInputLanguage(validLanguage.getId());
 
 		Logger.w("tt9/validateSavedLanguage", error + " Enforcing language: " + validLanguage.getId());

src/io/github/sspanak/tt9/languages/Language.java

@@ -8,7 +8,7 @@ import java.util.Locale;
 
 
 public class Language {
-	protected int id;
+	private int id;
 	protected String name;
 	protected Locale locale;
 	protected int icon;
@@ -22,6 +22,10 @@ public class Language {
 	protected boolean isPunctuationPartOfWords; // see the getter for more info
 
 	final public int getId() {
+		if (id == 0) {
+			id = generateId();
+		}
+
 		return id;
 	}
 
@@ -45,7 +49,6 @@ public class Language {
 		return lowerCase ? abcLowerCaseIcon : abcUpperCaseIcon;
 	}
 
-
 	/**
 	 * isPunctuationPartOfWords
 	 * This plays a role in Predictive mode only.
@@ -67,6 +70,34 @@ public class Language {
 
 	/* ************ utility ************ */
 
+	/**
+	 * generateId
+	 * Uses the letters of the Locale to generate an ID for the language.
+	 * Each letter is converted to uppercase and used as n 5-bit integer. Then the the 5-bits
+	 * are packed to form a 10-bit or a 20-bit integer, depending on the Locale.
+	 *
+	 * Example (2-letter Locale)
+	 * 	"en"
+	 * 	-> "E" | "N"
+	 * 	-> 5 | 448 (shift the 2nd number by 5 bits, so its bits would not overlap with the 1st one)
+	 *	-> 543
+	 *
+	 * Example (4-letter Locale)
+	 * 	"bg-BG"
+	 * 	-> "B" | "G" | "B" | "G"
+	 * 	-> 2 | 224 | 2048 | 229376 (shift each 5-bit number, not overlap with the previous ones)
+	 *	-> 231650
+	 */
+	private int generateId() {
+		String idString = (locale.getLanguage() + locale.getCountry()).toUpperCase();
+		int idInt = 0;
+		for (int i = 0; i < idString.length(); i++) {
+			idInt |= ((idString.charAt(i) & 31) << (i * 5));
+		}
+
+		return idInt;
+	}
+
 	private void generateReverseCharacterMap() {
 		reverseCharacterMap.clear();
 		for (int digit = 0; digit <= 9; digit++) {
@@ -76,7 +107,6 @@ public class Language {
 		}
 	}
 
-
 	public String capitalize(String word) {
 		return word != null ? word.substring(0, 1).toUpperCase(locale) + word.substring(1).toLowerCase(locale) : null;
 	}

src/io/github/sspanak/tt9/languages/LanguageCollection.java

@@ -14,6 +14,7 @@ import io.github.sspanak.tt9.languages.definitions.*;
 public class LanguageCollection {
 	private static LanguageCollection self;
 
+	private final Language defaultLanguage = new English();
 	private final HashMap<Integer, Language> languages = new HashMap<>();
 
 	private LanguageCollection() {
@@ -61,6 +62,10 @@ public class LanguageCollection {
 		return null;
 	}
 
+	public static Language getDefault() {
+		return getInstance().defaultLanguage;
+	}
+
 	public static ArrayList<Language> getAll(ArrayList<Integer> languageIds, boolean sort) {
 		ArrayList<Language> langList = new ArrayList<>();
 

src/io/github/sspanak/tt9/languages/definitions/Bulgarian.java

@@ -10,7 +10,6 @@ import io.github.sspanak.tt9.languages.Characters;
 
 public class Bulgarian extends Language {
 	public Bulgarian() {
-		id = 7;
 		name = "Български";
 		locale = new Locale("bg","BG");
 		dictionaryFile = "bg-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/Dutch.java

@@ -9,7 +9,6 @@ public class Dutch extends English {
 	public Dutch() {
 		super();
 
-		id = 8;
 		name = "Nederlands";
 		locale = new Locale("nl","NL");
 		dictionaryFile = "nl-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/English.java

@@ -10,7 +10,6 @@ import io.github.sspanak.tt9.languages.Characters;
 
 public class English extends Language {
 	public English() {
-		id = 1;
 		name = "English";
 		locale = Locale.ENGLISH;
 		dictionaryFile = "en-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/French.java

@@ -9,7 +9,6 @@ public class French extends English {
 	public French() {
 		super();
 
-		id = 4;
 		name = "Français";
 		locale = Locale.FRENCH;
 		dictionaryFile = "fr-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/German.java

@@ -8,7 +8,6 @@ public class German extends English {
 	public German() {
 		super();
 
-		id = 3;
 		name = "Deutsch";
 		locale = Locale.GERMAN;
 		dictionaryFile = "de-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/Italian.java

@@ -9,7 +9,6 @@ public class Italian extends English {
 	public Italian() {
 		super();
 
-		id = 5;
 		name = "Italiano";
 		locale = Locale.ITALIAN;
 		dictionaryFile = "it-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/Russian.java

@@ -10,7 +10,6 @@ import io.github.sspanak.tt9.languages.Characters;
 
 public class Russian extends Language {
 	public Russian() {
-		id = 2;
 		name = "Русский";
 		locale = new Locale("ru","RU");
 		dictionaryFile = "ru-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/Spanish.java

@@ -12,7 +12,6 @@ public class Spanish extends English {
 	public Spanish() {
 		super();
 
-		id = 9;
 		name = "Español";
 		locale = new Locale("es", "ES");
 		dictionaryFile = "es-utf8.csv";

src/io/github/sspanak/tt9/languages/definitions/Ukrainian.java

@@ -10,7 +10,6 @@ import io.github.sspanak.tt9.languages.Characters;
 
 public class Ukrainian extends Language {
 	public Ukrainian() {
-		id = 6;
 		name = "Українська";
 		locale = new Locale("uk","UA");
 		dictionaryFile = "uk-utf8.csv";

src/io/github/sspanak/tt9/preferences/PreferencesActivity.java

@@ -14,6 +14,7 @@ import androidx.preference.PreferenceFragmentCompat;
 import io.github.sspanak.tt9.R;
 import io.github.sspanak.tt9.db.DictionaryDb;
 import io.github.sspanak.tt9.db.DictionaryLoader;
+import io.github.sspanak.tt9.ime.helpers.InputModeValidator;
 import io.github.sspanak.tt9.preferences.screens.AppearanceScreen;
 import io.github.sspanak.tt9.preferences.screens.DictionariesScreen;
 import io.github.sspanak.tt9.preferences.screens.HotkeysScreen;
@@ -33,6 +34,8 @@ public class PreferencesActivity extends AppCompatActivity implements Preference
 		DictionaryDb.init(this);
 		DictionaryDb.normalizeWordFrequencies(settings);
 
+		InputModeValidator.validateEnabledLanguages(settings, settings.getEnabledLanguageIds());
+
 		super.onCreate(savedInstanceState);
 		validateFunctionKeys();
 		buildLayout();
@@ -125,7 +128,7 @@ public class PreferencesActivity extends AppCompatActivity implements Preference
 
 
 	private void validateFunctionKeys() {
-		if (!settings.areFunctionKeysSet()) {
+		if (settings.isSettingsKeyMissing()) {
 			settings.setDefaultKeys();
 		}
 	}

src/io/github/sspanak/tt9/preferences/SettingsStore.java

@@ -70,7 +70,9 @@ public class SettingsStore {
 	}
 
 	public Set<String> getEnabledLanguagesIdsAsStrings() {
-		return prefs.getStringSet("pref_languages", new HashSet<>(Collections.singletonList("1")));
+		return prefs.getStringSet("pref_languages", new HashSet<>(Collections.singletonList(
+			String.valueOf(LanguageCollection.getDefault().getId())
+		)));
 	}
 
 	public void saveEnabledLanguageIds(ArrayList<Integer> languageIds) {
@@ -123,7 +125,7 @@ public class SettingsStore {
 
 
 	public int getInputLanguage() {
-		return prefs.getInt("pref_input_language", 1);
+		return prefs.getInt("pref_input_language", LanguageCollection.getDefault().getId());
 	}
 
 	public void saveInputLanguage(int language) {
@@ -151,8 +153,8 @@ public class SettingsStore {
 
 	/************* function key settings *************/
 
-	public boolean areFunctionKeysSet() {
+	public boolean isSettingsKeyMissing() {
-		return getKeyShowSettings() != 0;
+		return getKeyShowSettings() == 0;
 	}
 
 	public void setDefaultKeys() {
@@ -198,7 +200,6 @@ public class SettingsStore {
 	public boolean getNotifyNextLanguageInModeAbc() { return prefs.getBoolean("notify_next_language_in_mode_abc", true); }
 
 	public boolean getDarkTheme() { return prefs.getBoolean("pref_dark_theme", true); }
-	public void setDarkTheme(boolean yes) { prefsEditor.putBoolean("pref_dark_theme", yes); }
 
 
 	public boolean getShowSoftKeys() { return prefs.getBoolean("pref_show_soft_keys", true); }

src/io/github/sspanak/tt9/preferences/helpers/Hotkeys.java

@@ -98,7 +98,7 @@ public class Hotkeys {
 
 	/**
 	 * generateList
-	 * These keys will appears as options only if Android says the device has them.
+	 * Generates a list of all supported hotkeys for associating functions in the Settings.
 	 *
 	 * NOTE: Some TT9 functions do not support all keys. Here you just list all possible options.
 	 * Actual validation and assigning happens in SectionKeymap.populate().

src/io/github/sspanak/tt9/preferences/items/ItemLoadDictionary.java

@@ -10,7 +10,7 @@ import androidx.preference.Preference;
 import java.util.ArrayList;
 
 import io.github.sspanak.tt9.R;
-import io.github.sspanak.tt9.db.DictionaryImportAlreadyRunningException;
+import io.github.sspanak.tt9.db.exceptions.DictionaryImportAlreadyRunningException;
 import io.github.sspanak.tt9.db.DictionaryLoader;
 import io.github.sspanak.tt9.languages.Language;
 import io.github.sspanak.tt9.languages.LanguageCollection;

src/io/github/sspanak/tt9/ui/AddWordAct.java

@@ -14,7 +14,7 @@ import androidx.appcompat.app.AppCompatDelegate;
 import io.github.sspanak.tt9.Logger;
 import io.github.sspanak.tt9.R;
 import io.github.sspanak.tt9.db.DictionaryDb;
-import io.github.sspanak.tt9.db.InsertBlankWordException;
+import io.github.sspanak.tt9.db.exceptions.InsertBlankWordException;
 import io.github.sspanak.tt9.languages.InvalidLanguageException;
 import io.github.sspanak.tt9.languages.LanguageCollection;
 import io.github.sspanak.tt9.preferences.SettingsStore;

src/io/github/sspanak/tt9/ui/DictionaryLoadingBar.java

@@ -14,7 +14,7 @@ import java.io.IOException;
 import java.util.Locale;
 
 import io.github.sspanak.tt9.R;
-import io.github.sspanak.tt9.db.DictionaryImportException;
+import io.github.sspanak.tt9.db.exceptions.DictionaryImportException;
 import io.github.sspanak.tt9.languages.InvalidLanguageCharactersException;
 import io.github.sspanak.tt9.languages.InvalidLanguageException;
 import io.github.sspanak.tt9.languages.Language;