upgrade build.gradle and do some code inspection stuff

app/build.gradle

@@ -90,14 +90,22 @@ android {
 }
 
 dependencies {
-    implementation 'androidx.core:core-ktx:1.12.0'
+    // androidx
+    implementation 'androidx.core:core-ktx:1.13.1'
     implementation 'androidx.preference:preference:1.2.1'
     implementation 'androidx.recyclerview:recyclerview:1.3.2'
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
-    implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3"
-    implementation 'com.github.martin-stone:hsv-alpha-color-picker-android:3.1.0'
     implementation 'androidx.autofill:autofill:1.1.0'
 
+    // kotlin
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
+    implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3"
+    // when kotlin-serialization is enabled, Android Studio stops complaining about "Unresolved reference: serializer", but the build fails
+//    implementation "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
+
+    // color picker for user-defined colors
+    implementation 'com.github.martin-stone:hsv-alpha-color-picker-android:3.1.0'
+
+    // test
     testImplementation 'junit:junit:4.13.2'
     testImplementation 'org.mockito:mockito-core:5.11.0'
     testImplementation 'org.mockito:mockito-inline:5.2.0'

app/src/main/java/helium314/keyboard/accessibility/AccessibilityUtils.kt

@@ -7,7 +7,6 @@
 package helium314.keyboard.accessibility
 
 import android.content.Context
-import android.media.AudioDeviceInfo
 import android.media.AudioDeviceInfo.*
 import android.media.AudioManager
 import android.os.Build

app/src/main/java/helium314/keyboard/accessibility/KeyboardAccessibilityDelegate.kt

@@ -47,10 +47,9 @@ open class KeyboardAccessibilityDelegate<KV : KeyboardView>(
     /**
      * Called when the keyboard layout changes.
      *
-     *
      * **Note:** This method will be called even if accessibility is not
      * enabled.
-     * @param keyboard The keyboard that is being set to the wrapping view.
+     * [keyboard]: The keyboard that is being set to the wrapping view.
      */
     open var keyboard: Keyboard?
         get() = mKeyboard

app/src/main/java/helium314/keyboard/accessibility/MainKeyboardAccessibilityDelegate.kt

@@ -116,8 +116,7 @@ class MainKeyboardAccessibilityDelegate(
      */
     private fun announceKeyboardType(keyboard: Keyboard, lastKeyboard: Keyboard) {
         val lastElementId = lastKeyboard.mId.mElementId
-        val resId: Int
+        val resId = when (keyboard.mId.mElementId) {
-        resId = when (keyboard.mId.mElementId) {
             KeyboardId.ELEMENT_ALPHABET_AUTOMATIC_SHIFTED, KeyboardId.ELEMENT_ALPHABET -> {
                 if (lastElementId == KeyboardId.ELEMENT_ALPHABET
                         || lastElementId == KeyboardId.ELEMENT_ALPHABET_AUTOMATIC_SHIFTED) {

app/src/main/java/helium314/keyboard/event/CombinerChain.kt

@@ -9,7 +9,6 @@ package helium314.keyboard.event
 import android.text.SpannableStringBuilder
 import android.text.TextUtils
 import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode
-import helium314.keyboard.latin.common.Constants
 import java.util.*
 
 /**
@@ -23,6 +22,12 @@ import java.util.*
  * finished combining part, will be shown normally as the composing string, while the second is
  * feedback on the composing state and will typically be shown with different styling such as
  * a colored background.
+ *
+ * The combiner chain takes events as inputs and outputs code points and combining state.
+ * For example, if the input language is Japanese, the combining chain will typically perform
+ * kana conversion. This takes a string for initial text, taken to be present before the
+ * cursor: we'll start after this.
+ * @param initialText The text that has already been combined so far.
  */
 class CombinerChain(initialText: String) {
     // The already combined text, as described above
@@ -45,16 +50,6 @@ class CombinerChain(initialText: String) {
                 mCombiners.add(HangulCombiner())
         }
 
-    /**
-     * Create an combiner chain.
-     *
-     * The combiner chain takes events as inputs and outputs code points and combining state.
-     * For example, if the input language is Japanese, the combining chain will typically perform
-     * kana conversion. This takes a string for initial text, taken to be present before the
-     * cursor: we'll start after this.
-     *
-     * @param initialText The text that has already been combined so far.
-     */
     init {
         // The dead key combiner is always active, and always first
         mCombiners.add(DeadKeyCombiner())

app/src/main/java/helium314/keyboard/event/InputTransaction.kt

@@ -28,7 +28,7 @@ class InputTransaction(// Initial conditions
      * @param updateType What type of shift update this requires.
      */
     fun requireShiftUpdate(updateType: Int) {
-        requiredShiftUpdate = Math.max(requiredShiftUpdate, updateType)
+        requiredShiftUpdate = requiredShiftUpdate.coerceAtLeast(updateType)
     }
 
     /**

app/src/main/java/helium314/keyboard/keyboard/Key.java

@@ -191,7 +191,7 @@ public class Key implements Comparable<Key> {
     /**
      * Constructor for a key on <code>PopupKeyKeyboard</code> and on <code>MoreSuggestions</code>.
      */
-    public Key(@Nullable final String label, final String iconName, final int code,
+    public Key(@Nullable final String label, @NonNull final String iconName, final int code,
             @Nullable final String outputText, @Nullable final String hintLabel,
             final int labelFlags, final int backgroundType, final int x, final int y,
             final int width, final int height, final int horizontalGap, final int verticalGap) {
@@ -404,7 +404,7 @@ public class Key implements Comparable<Key> {
                 && o.mCode == mCode
                 && TextUtils.equals(o.mLabel, mLabel)
                 && TextUtils.equals(o.mHintLabel, mHintLabel)
-                && o.mIconName == mIconName
+                && o.mIconName.equals(mIconName)
                 && o.mBackgroundType == mBackgroundType
                 && Arrays.equals(o.mPopupKeys, mPopupKeys)
                 && TextUtils.equals(o.getOutputText(), getOutputText())
@@ -429,6 +429,7 @@ public class Key implements Comparable<Key> {
         return o instanceof Key && equalsInternal((Key)o);
     }
 
+    @NonNull
     @Override
     public String toString() {
         return toShortString() + " " + getX() + "," + getY() + " " + getWidth() + "x" + getHeight();
@@ -654,7 +655,7 @@ public class Key implements Comparable<Key> {
         return (mLabelFlags & LABEL_FLAGS_FROM_CUSTOM_ACTION_LABEL) != 0;
     }
 
-    private final boolean isShiftedLetterActivated() {
+    private boolean isShiftedLetterActivated() {
         return (mLabelFlags & LABEL_FLAGS_SHIFTED_LETTER_ACTIVATED) != 0
                 && !TextUtils.isEmpty(mHintLabel);
     }

app/src/main/java/helium314/keyboard/keyboard/KeyboardActionListener.java

@@ -35,11 +35,11 @@ public interface KeyboardActionListener {
      * Send a key code to the listener.
      *
      * @param primaryCode this is the code of the key that was pressed
-     * @param x x-coordinate pixel of touched event. If {@link #onCodeInput} is not called by
+     * @param x x-coordinate pixel of touched event. If onCodeInput is not called by
      *            {@link PointerTracker} or so, the value should be
      *            {@link Constants#NOT_A_COORDINATE}. If it's called on insertion from the
      *            suggestion strip, it should be {@link Constants#SUGGESTION_STRIP_COORDINATE}.
-     * @param y y-coordinate pixel of touched event. If {@link #onCodeInput} is not called by
+     * @param y y-coordinate pixel of touched event. If #onCodeInput is not called by
      *            {@link PointerTracker} or so, the value should be
      *            {@link Constants#NOT_A_COORDINATE}.If it's called on insertion from the
      *            suggestion strip, it should be {@link Constants#SUGGESTION_STRIP_COORDINATE}.
@@ -103,9 +103,9 @@ public interface KeyboardActionListener {
 
     KeyboardActionListener EMPTY_LISTENER = new Adapter();
 
-    static int SWIPE_NO_ACTION = 0;
+    int SWIPE_NO_ACTION = 0;
-    static int SWIPE_MOVE_CURSOR = 1;
+    int SWIPE_MOVE_CURSOR = 1;
-    static int SWIPE_SWITCH_LANGUAGE = 2;
+    int SWIPE_SWITCH_LANGUAGE = 2;
 
     class Adapter implements KeyboardActionListener {
         @Override

app/src/main/java/helium314/keyboard/keyboard/KeyboardActionListenerImpl.kt

@@ -97,9 +97,9 @@ class KeyboardActionListenerImpl(private val latinIME: LatinIME, private val inp
         return true
     }
 
-    private fun onMoveCursorHorizontally(_steps: Int): Boolean {
+    private fun onMoveCursorHorizontally(rawSteps: Int): Boolean {
-        if (_steps == 0) return false
+        if (rawSteps == 0) return false
-        var steps = _steps
+        var steps = rawSteps
         // for RTL languages we want to invert pointer movement
         if (RichInputMethodManager.getInstance().currentSubtype.isRtlSubtype) steps = -steps
         val moveSteps: Int

app/src/main/java/helium314/keyboard/keyboard/clipboard/ClipboardHistoryView.kt

@@ -32,6 +32,7 @@ import helium314.keyboard.latin.utils.getCodeForToolbarKey
 import helium314.keyboard.latin.utils.getCodeForToolbarKeyLongClick
 import helium314.keyboard.latin.utils.getEnabledClipboardToolbarKeys
 
+@SuppressLint("CustomViewStyleable")
 class ClipboardHistoryView @JvmOverloads constructor(
         context: Context,
         attrs: AttributeSet?,
@@ -160,7 +161,7 @@ class ClipboardHistoryView @JvmOverloads constructor(
 
     private fun setupToolbarKeys() {
         // set layout params
-        val toolbarKeyLayoutParams = LayoutParams(getResources().getDimensionPixelSize(R.dimen.config_suggestions_strip_edge_key_width), LayoutParams.MATCH_PARENT)
+        val toolbarKeyLayoutParams = LayoutParams(resources.getDimensionPixelSize(R.dimen.config_suggestions_strip_edge_key_width), LayoutParams.MATCH_PARENT)
         toolbarKeys.forEach { it.layoutParams = toolbarKeyLayoutParams }
     }
 

app/src/main/java/helium314/keyboard/keyboard/emoji/DynamicGridKeyboard.java

@@ -236,8 +236,7 @@ final class DynamicGridKeyboard extends Keyboard {
             if (o instanceof Integer) {
                 final int code = (Integer)o;
                 key = getKeyByCode(keyboards, code);
-            } else if (o instanceof String) {
+            } else if (o instanceof final String outputText) {
-                final String outputText = (String)o;
                 key = getKeyByOutputText(keyboards, outputText);
             } else {
                 Log.w(TAG, "Invalid object: " + o);
@@ -267,18 +266,20 @@ final class DynamicGridKeyboard extends Keyboard {
         return row * mVerticalStep + mVerticalGap / 2;
     }
 
+    @NonNull
     @Override
     public List<Key> getSortedKeys() {
         synchronized (mLock) {
             if (mCachedGridKeys != null) {
                 return mCachedGridKeys;
             }
-            final ArrayList<Key> cachedKeys = new ArrayList<Key>(mGridKeys);
+            final ArrayList<Key> cachedKeys = new ArrayList<>(mGridKeys);
             mCachedGridKeys = Collections.unmodifiableList(cachedKeys);
             return mCachedGridKeys;
         }
     }
 
+    @NonNull
     @Override
     public List<Key> getNearestKeys(final int x, final int y) {
         // TODO: Calculate the nearest key index in mGridKeys from x and y.
@@ -312,13 +313,13 @@ final class DynamicGridKeyboard extends Keyboard {
 
         @Override
         public boolean equals(final Object o) {
-            if (!(o instanceof Key)) return false;
+            if (!(o instanceof final Key key)) return false;
-            final Key key = (Key)o;
             if (getCode() != key.getCode()) return false;
             if (!TextUtils.equals(getLabel(), key.getLabel())) return false;
             return TextUtils.equals(getOutputText(), key.getOutputText());
         }
 
+        @NonNull
         @Override
         public String toString() {
             return "GridKey: " + super.toString();

app/src/main/java/helium314/keyboard/keyboard/internal/keyboard_parser/RawKeyboardParser.kt

@@ -121,6 +121,7 @@ object RawKeyboardParser {
         else -> params.mId.mSubtype.keyboardLayoutSetName.substringBeforeLast("+")
     }
 
+    // todo (later, see also keyboardParser): use Settings.getInstance().current.mSingleFunctionalLayout
     private fun getFunctionalLayoutName(params: KeyboardParams) = when (params.mId.mElementId) {
         KeyboardId.ELEMENT_SYMBOLS_SHIFTED -> FUNCTIONAL_LAYOUT_SYMBOLS_SHIFTED
         KeyboardId.ELEMENT_SYMBOLS -> FUNCTIONAL_LAYOUT_SYMBOLS

app/src/main/java/helium314/keyboard/latin/AudioAndHapticFeedbackManager.java

@@ -18,7 +18,7 @@ import helium314.keyboard.latin.settings.SettingsValues;
 
 /**
  * This class gathers audio feedback and haptic feedback functions.
- *
+ * <p>
  * It offers a consistent and simple interface that allows LatinIME to forget about the
  * complexity of settings and the like.
  */
@@ -81,21 +81,12 @@ public final class AudioAndHapticFeedbackManager {
         if (!mSoundOn) {
             return;
         }
-        final int sound;
+        final int sound = switch (code) {
-        switch (code) {
+            case KeyCode.DELETE -> AudioManager.FX_KEYPRESS_DELETE;
-        case KeyCode.DELETE:
+            case Constants.CODE_ENTER -> AudioManager.FX_KEYPRESS_RETURN;
-            sound = AudioManager.FX_KEYPRESS_DELETE;
+            case Constants.CODE_SPACE -> AudioManager.FX_KEYPRESS_SPACEBAR;
-            break;
+            default -> AudioManager.FX_KEYPRESS_STANDARD;
-        case Constants.CODE_ENTER:
+        };
-            sound = AudioManager.FX_KEYPRESS_RETURN;
-            break;
-        case Constants.CODE_SPACE:
-            sound = AudioManager.FX_KEYPRESS_SPACEBAR;
-            break;
-        default:
-            sound = AudioManager.FX_KEYPRESS_STANDARD;
-            break;
-        }
         mAudioManager.playSoundEffect(sound, mSettingsValues.mKeypressSoundVolume);
     }
 

app/src/main/java/helium314/keyboard/latin/ContactsManager.java

@@ -25,7 +25,7 @@ import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * Manages all interactions with Contacts DB.
- *
+ * <p>
  * The manager provides an API for listening to meaning full updates by keeping a
  * measure of the current state of the content provider.
  */
@@ -65,7 +65,7 @@ public class ContactsManager {
          * - How many times it has been contacted
          * - How long since the last contact.
          * - Whether the contact is in the visible group (i.e., Contacts list).
-         *
+         * <p>
          * Note: This affinity is limited by the fact that some apps currently do not update the
          * LAST_TIME_CONTACTED or TIMES_CONTACTED counters. As a result, a frequently messaged
          * contact may still have 0 affinity.
@@ -101,13 +101,13 @@ public class ContactsManager {
      * The number of contacts observed in the most recent instance of
      * contacts content provider.
      */
-    private AtomicInteger mContactCountAtLastRebuild = new AtomicInteger(0);
+    private final AtomicInteger mContactCountAtLastRebuild = new AtomicInteger(0);
 
     /**
      * The hash code of list of valid contacts names in the most recent dictionary
      * rebuild.
      */
-    private AtomicInteger mHashCodeAtLastRebuild = new AtomicInteger(0);
+    private final AtomicInteger mHashCodeAtLastRebuild = new AtomicInteger(0);
 
     private final Context mContext;
     private final ContactsContentObserver mObserver;
@@ -134,7 +134,7 @@ public class ContactsManager {
      * Returns all the valid names in the Contacts DB. Callers should also
      * call {@link #updateLocalState(ArrayList)} after they are done with result
      * so that the manager can cache local state for determining updates.
-     *
+     * <p>
      * These names are sorted by their affinity to the user, with favorite
      * contacts appearing first.
      */
@@ -183,22 +183,15 @@ public class ContactsManager {
      * Returns the number of contacts in contacts content provider.
      */
     public int getContactCount() {
-        // TODO: consider switching to a rawQuery("select count(*)...") on the database if
+        // TODO: consider switching to a rawQuery("select count(*)...") on the database if performance is a bottleneck.
-        // performance is a bottleneck.
+        try (Cursor cursor = mContext.getContentResolver().query(Contacts.CONTENT_URI,
-        Cursor cursor = null;
+                ContactsDictionaryConstants.PROJECTION_ID_ONLY, null, null, null)
-        try {
+        ) {
-            cursor = mContext.getContentResolver().query(Contacts.CONTENT_URI,
+            if (null == cursor)
-                    ContactsDictionaryConstants.PROJECTION_ID_ONLY, null, null, null);
-            if (null == cursor) {
                 return 0;
-            }
             return cursor.getCount();
         } catch (final SQLiteException e) {
             Log.e(TAG, "SQLiteException in the remote Contacts process.", e);
-        } finally {
-            if (null != cursor) {
-                cursor.close();
-            }
         }
         return 0;
     }

app/src/main/java/helium314/keyboard/latin/InputAttributes.java

@@ -20,6 +20,8 @@ import java.util.Arrays;
 import static helium314.keyboard.latin.common.Constants.ImeOption.NO_FLOATING_GESTURE_PREVIEW;
 import static helium314.keyboard.latin.common.Constants.ImeOption.NO_MICROPHONE;
 
+import androidx.annotation.NonNull;
+
 /**
  * Class to hold attributes of the input field.
  */
@@ -162,92 +164,60 @@ public final class InputAttributes {
     }
 
     private static String toInputClassString(final int inputClass) {
-        switch (inputClass) {
+        return switch (inputClass) {
-        case InputType.TYPE_CLASS_TEXT:
+            case InputType.TYPE_CLASS_TEXT -> "TYPE_CLASS_TEXT";
-            return "TYPE_CLASS_TEXT";
+            case InputType.TYPE_CLASS_PHONE -> "TYPE_CLASS_PHONE";
-        case InputType.TYPE_CLASS_PHONE:
+            case InputType.TYPE_CLASS_NUMBER -> "TYPE_CLASS_NUMBER";
-            return "TYPE_CLASS_PHONE";
+            case InputType.TYPE_CLASS_DATETIME -> "TYPE_CLASS_DATETIME";
-        case InputType.TYPE_CLASS_NUMBER:
+            default -> String.format("unknownInputClass<0x%08x>", inputClass);
-            return "TYPE_CLASS_NUMBER";
+        };
-        case InputType.TYPE_CLASS_DATETIME:
-            return "TYPE_CLASS_DATETIME";
-        default:
-            return String.format("unknownInputClass<0x%08x>", inputClass);
-        }
     }
 
     private static String toVariationString(final int inputClass, final int variation) {
-        switch (inputClass) {
+        return switch (inputClass) {
-        case InputType.TYPE_CLASS_TEXT:
+            case InputType.TYPE_CLASS_TEXT -> toTextVariationString(variation);
-            return toTextVariationString(variation);
+            case InputType.TYPE_CLASS_NUMBER -> toNumberVariationString(variation);
-        case InputType.TYPE_CLASS_NUMBER:
+            case InputType.TYPE_CLASS_DATETIME -> toDatetimeVariationString(variation);
-            return toNumberVariationString(variation);
+            default -> "";
-        case InputType.TYPE_CLASS_DATETIME:
+        };
-            return toDatetimeVariationString(variation);
-        default:
-            return "";
-        }
     }
 
     private static String toTextVariationString(final int variation) {
-        switch (variation) {
+        return switch (variation) {
-        case InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS:
+            case InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS -> " TYPE_TEXT_VARIATION_EMAIL_ADDRESS";
-            return " TYPE_TEXT_VARIATION_EMAIL_ADDRESS";
+            case InputType.TYPE_TEXT_VARIATION_EMAIL_SUBJECT -> "TYPE_TEXT_VARIATION_EMAIL_SUBJECT";
-        case InputType.TYPE_TEXT_VARIATION_EMAIL_SUBJECT:
+            case InputType.TYPE_TEXT_VARIATION_FILTER -> "TYPE_TEXT_VARIATION_FILTER";
-            return "TYPE_TEXT_VARIATION_EMAIL_SUBJECT";
+            case InputType.TYPE_TEXT_VARIATION_LONG_MESSAGE -> "TYPE_TEXT_VARIATION_LONG_MESSAGE";
-        case InputType.TYPE_TEXT_VARIATION_FILTER:
+            case InputType.TYPE_TEXT_VARIATION_NORMAL -> "TYPE_TEXT_VARIATION_NORMAL";
-            return "TYPE_TEXT_VARIATION_FILTER";
+            case InputType.TYPE_TEXT_VARIATION_PASSWORD -> "TYPE_TEXT_VARIATION_PASSWORD";
-        case InputType.TYPE_TEXT_VARIATION_LONG_MESSAGE:
+            case InputType.TYPE_TEXT_VARIATION_PERSON_NAME -> "TYPE_TEXT_VARIATION_PERSON_NAME";
-            return "TYPE_TEXT_VARIATION_LONG_MESSAGE";
+            case InputType.TYPE_TEXT_VARIATION_PHONETIC -> "TYPE_TEXT_VARIATION_PHONETIC";
-        case InputType.TYPE_TEXT_VARIATION_NORMAL:
+            case InputType.TYPE_TEXT_VARIATION_POSTAL_ADDRESS -> "TYPE_TEXT_VARIATION_POSTAL_ADDRESS";
-            return "TYPE_TEXT_VARIATION_NORMAL";
+            case InputType.TYPE_TEXT_VARIATION_SHORT_MESSAGE -> "TYPE_TEXT_VARIATION_SHORT_MESSAGE";
-        case InputType.TYPE_TEXT_VARIATION_PASSWORD:
+            case InputType.TYPE_TEXT_VARIATION_URI -> "TYPE_TEXT_VARIATION_URI";
-            return "TYPE_TEXT_VARIATION_PASSWORD";
+            case InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD -> "TYPE_TEXT_VARIATION_VISIBLE_PASSWORD";
-        case InputType.TYPE_TEXT_VARIATION_PERSON_NAME:
+            case InputType.TYPE_TEXT_VARIATION_WEB_EDIT_TEXT -> "TYPE_TEXT_VARIATION_WEB_EDIT_TEXT";
-            return "TYPE_TEXT_VARIATION_PERSON_NAME";
+            case InputType.TYPE_TEXT_VARIATION_WEB_EMAIL_ADDRESS -> "TYPE_TEXT_VARIATION_WEB_EMAIL_ADDRESS";
-        case InputType.TYPE_TEXT_VARIATION_PHONETIC:
+            case InputType.TYPE_TEXT_VARIATION_WEB_PASSWORD -> "TYPE_TEXT_VARIATION_WEB_PASSWORD";
-            return "TYPE_TEXT_VARIATION_PHONETIC";
+            default -> String.format("unknownVariation<0x%08x>", variation);
-        case InputType.TYPE_TEXT_VARIATION_POSTAL_ADDRESS:
+        };
-            return "TYPE_TEXT_VARIATION_POSTAL_ADDRESS";
-        case InputType.TYPE_TEXT_VARIATION_SHORT_MESSAGE:
-            return "TYPE_TEXT_VARIATION_SHORT_MESSAGE";
-        case InputType.TYPE_TEXT_VARIATION_URI:
-            return "TYPE_TEXT_VARIATION_URI";
-        case InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD:
-            return "TYPE_TEXT_VARIATION_VISIBLE_PASSWORD";
-        case InputType.TYPE_TEXT_VARIATION_WEB_EDIT_TEXT:
-            return "TYPE_TEXT_VARIATION_WEB_EDIT_TEXT";
-        case InputType.TYPE_TEXT_VARIATION_WEB_EMAIL_ADDRESS:
-            return "TYPE_TEXT_VARIATION_WEB_EMAIL_ADDRESS";
-        case InputType.TYPE_TEXT_VARIATION_WEB_PASSWORD:
-            return "TYPE_TEXT_VARIATION_WEB_PASSWORD";
-        default:
-            return String.format("unknownVariation<0x%08x>", variation);
-        }
     }
 
     private static String toNumberVariationString(final int variation) {
-        switch (variation) {
+        return switch (variation) {
-        case InputType.TYPE_NUMBER_VARIATION_NORMAL:
+            case InputType.TYPE_NUMBER_VARIATION_NORMAL -> "TYPE_NUMBER_VARIATION_NORMAL";
-            return "TYPE_NUMBER_VARIATION_NORMAL";
+            case InputType.TYPE_NUMBER_VARIATION_PASSWORD -> "TYPE_NUMBER_VARIATION_PASSWORD";
-        case InputType.TYPE_NUMBER_VARIATION_PASSWORD:
+            default -> String.format("unknownVariation<0x%08x>", variation);
-            return "TYPE_NUMBER_VARIATION_PASSWORD";
+        };
-        default:
-            return String.format("unknownVariation<0x%08x>", variation);
-        }
     }
 
     private static String toDatetimeVariationString(final int variation) {
-        switch (variation) {
+        return switch (variation) {
-        case InputType.TYPE_DATETIME_VARIATION_NORMAL:
+            case InputType.TYPE_DATETIME_VARIATION_NORMAL -> "TYPE_DATETIME_VARIATION_NORMAL";
-            return "TYPE_DATETIME_VARIATION_NORMAL";
+            case InputType.TYPE_DATETIME_VARIATION_DATE -> "TYPE_DATETIME_VARIATION_DATE";
-        case InputType.TYPE_DATETIME_VARIATION_DATE:
+            case InputType.TYPE_DATETIME_VARIATION_TIME -> "TYPE_DATETIME_VARIATION_TIME";
-            return "TYPE_DATETIME_VARIATION_DATE";
+            default -> String.format("unknownVariation<0x%08x>", variation);
-        case InputType.TYPE_DATETIME_VARIATION_TIME:
+        };
-            return "TYPE_DATETIME_VARIATION_TIME";
-        default:
-            return String.format("unknownVariation<0x%08x>", variation);
-        }
     }
 
     private static String toFlagsString(final int flags) {
@@ -272,6 +242,7 @@ public final class InputAttributes {
     }
 
     // Pretty print
+    @NonNull
     @Override
     public String toString() {
         return String.format(

app/src/main/java/helium314/keyboard/latin/LatinIME.java

@@ -6,6 +6,7 @@
 
 package helium314.keyboard.latin;
 
+import android.annotation.SuppressLint;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
@@ -783,6 +784,7 @@ public class LatinIME extends InputMethodService implements
      * Starts from {@link android.os.Build.VERSION_CODES#S_V2}, the returning context object has
      * became to IME context self since it ends up capable of updating its resources internally.
      */
+    @SuppressWarnings("deprecation")
     private @NonNull Context getDisplayContext() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S_V2) {
             // IME context sources is now managed by WindowProviderService from Android 12L.
@@ -1104,10 +1106,6 @@ public class LatinIME extends InputMethodService implements
         }
     }
 
-    public CharSequence getSelection() {
-        return mInputLogic.mConnection.getSelectedText(0);
-    }
-
     /**
      * This is called when the user has clicked on the extracted text view,
      * when running in fullscreen mode.  The default implementation hides
@@ -1667,14 +1665,11 @@ public class LatinIME extends InputMethodService implements
      */
     private void updateStateAfterInputTransaction(final InputTransaction inputTransaction) {
         switch (inputTransaction.getRequiredShiftUpdate()) {
-            case InputTransaction.SHIFT_UPDATE_LATER:
+            case InputTransaction.SHIFT_UPDATE_LATER -> mHandler.postUpdateShiftState();
-                mHandler.postUpdateShiftState();
+            case InputTransaction.SHIFT_UPDATE_NOW -> mKeyboardSwitcher
-                break;
+                    .requestUpdatingShiftState(getCurrentAutoCapsState(), getCurrentRecapitalizeState());
-            case InputTransaction.SHIFT_UPDATE_NOW:
+            default -> {
-                mKeyboardSwitcher.requestUpdatingShiftState(getCurrentAutoCapsState(),
+            } // SHIFT_NO_UPDATE
-                        getCurrentRecapitalizeState());
-                break;
-            default: // SHIFT_NO_UPDATE
         }
         if (inputTransaction.requiresUpdateSuggestions()) {
             final int inputStyle;
@@ -1897,6 +1892,7 @@ public class LatinIME extends InputMethodService implements
         }
     }
 
+    @SuppressLint("SwitchIntDef")
     @Override
     public void onTrimMemory(int level) {
         super.onTrimMemory(level);

app/src/main/java/helium314/keyboard/latin/PunctuationSuggestions.java

@@ -6,11 +6,11 @@
 
 package helium314.keyboard.latin;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import helium314.keyboard.keyboard.internal.KeySpecParser;
 import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode;
-import helium314.keyboard.latin.common.Constants;
 import helium314.keyboard.latin.common.StringUtils;
 
 import java.util.ArrayList;
@@ -18,7 +18,7 @@ import java.util.Arrays;
 
 /**
  * The extended {@link SuggestedWords} class to represent punctuation suggestions.
- *
+ * <p>
  * Each punctuation specification string is the key specification that can be parsed by
  * {@link KeySpecParser}.
  */
@@ -44,7 +44,7 @@ public final class PunctuationSuggestions extends SuggestedWords {
     public static PunctuationSuggestions newPunctuationSuggestions(
             @Nullable final String[] punctuationSpecs) {
         if (punctuationSpecs == null || punctuationSpecs.length == 0) {
-            return new PunctuationSuggestions(new ArrayList<SuggestedWordInfo>(0));
+            return new PunctuationSuggestions(new ArrayList<>(0));
         }
         final ArrayList<SuggestedWordInfo> punctuationList =
                 new ArrayList<>(punctuationSpecs.length);
@@ -99,7 +99,7 @@ public final class PunctuationSuggestions extends SuggestedWords {
     }
 
     @Override
-    public String toString() {
+    @NonNull public String toString() {
         return "PunctuationSuggestions: "
                 + " words=" + Arrays.toString(mSuggestedWordInfoList.toArray());
     }

app/src/main/java/helium314/keyboard/latin/WordComposer.java

@@ -15,7 +15,6 @@ import helium314.keyboard.keyboard.KeyboardSwitcher;
 import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode;
 import helium314.keyboard.latin.SuggestedWords.SuggestedWordInfo;
 import helium314.keyboard.latin.common.ComposedData;
-import helium314.keyboard.latin.common.Constants;
 import helium314.keyboard.latin.common.CoordinateUtils;
 import helium314.keyboard.latin.common.InputPointers;
 import helium314.keyboard.latin.common.StringUtils;
@@ -167,7 +166,7 @@ public final class WordComposer {
 
     /**
      * Apply a processed input event.
-     *
+     * <p>
      * All input events should be supported, including software/hardware events, characters as well
      * as deletions, multiple inputs and gestures.
      *
@@ -320,7 +319,7 @@ public final class WordComposer {
     /**
      * Whether this composer is composing or about to compose a word in which only the first letter
      * is a capital.
-     *
+     * <p>
      * If we do have a composing word, we just return whether the word has indeed only its first
      * character capitalized. If we don't, then we return a value based on the capitalized mode,
      * which tell us what is likely to happen for the next composing word.
@@ -370,7 +369,7 @@ public final class WordComposer {
 
     /**
      * Saves the caps mode at the start of composing.
-     *
+     * <p>
      * WordComposer needs to know about the caps mode for several reasons. The first is, we need
      * to know after the fact what the reason was, to register the correct form into the user
      * history dictionary: if the word was automatically capitalized, we should insert it in
@@ -385,7 +384,7 @@ public final class WordComposer {
 
     /**
      * Before fetching suggestions, we don't necessarily know about the capitalized mode yet.
-     *
+     * <p>
      * If we don't have a composing word yet, we take a note of this mode so that we can then
      * supply this information to the suggestion process. If we have a composing word, then
      * the previous mode has priority over this.

app/src/main/java/helium314/keyboard/latin/common/LocaleUtils.kt

@@ -58,7 +58,7 @@ object LocaleUtils {
     // The compared locales are fully identical. This is the best match level.
     private const val LOCALE_FULL_MATCH = 30
 
-    const val LOCALE_GOOD_MATCH = LOCALE_LANGUAGE_MATCH_COUNTRY_DIFFER;
+    const val LOCALE_GOOD_MATCH = LOCALE_LANGUAGE_MATCH_COUNTRY_DIFFER
 
     /**
      * Return how well a tested locale matches a reference locale.

app/src/main/java/helium314/keyboard/latin/inputlogic/InputLogicHandler.java

@@ -82,12 +82,8 @@ class InputLogicHandler implements Handler.Callback {
     // Called on the Non-UI handler thread by the Handler code.
     @Override
     public boolean handleMessage(final Message msg) {
-        switch (msg.what) {
+        if (msg.what == MSG_GET_SUGGESTED_WORDS)
-            case MSG_GET_SUGGESTED_WORDS:
+            mLatinIME.getSuggestedWords(msg.arg1, msg.arg2, (OnGetSuggestedWordsCallback) msg.obj);
-                mLatinIME.getSuggestedWords(msg.arg1 /* inputStyle */,
-                        msg.arg2 /* sequenceNumber */, (OnGetSuggestedWordsCallback) msg.obj);
-                break;
-        }
         return true;
     }
 
@@ -122,12 +118,7 @@ class InputLogicHandler implements Handler.Callback {
                 return;
             }
             mInputLogic.mWordComposer.setBatchInputPointers(batchPointers);
-            final OnGetSuggestedWordsCallback callback = new OnGetSuggestedWordsCallback() {
+            final OnGetSuggestedWordsCallback callback = suggestedWords -> showGestureSuggestionsWithPreviewVisuals(suggestedWords, isTailBatchInput);
-                @Override
-                public void onGetSuggestedWords(final SuggestedWords suggestedWords) {
-                    showGestureSuggestionsWithPreviewVisuals(suggestedWords, isTailBatchInput);
-                }
-            };
             getSuggestedWords(isTailBatchInput ? SuggestedWords.INPUT_STYLE_TAIL_BATCH
                     : SuggestedWords.INPUT_STYLE_UPDATE_BATCH, sequenceNumber, callback);
         }
@@ -159,7 +150,7 @@ class InputLogicHandler implements Handler.Callback {
 
     /**
      * Update a batch input.
-     *
+     * <p>
      * This fetches suggestions and updates the suggestion strip and the floating text preview.
      *
      * @param batchPointers the updated batch pointers.
@@ -168,12 +159,12 @@ class InputLogicHandler implements Handler.Callback {
     // Called on the UI thread by InputLogic.
     public void onUpdateBatchInput(final InputPointers batchPointers,
             final int sequenceNumber) {
-        updateBatchInput(batchPointers, sequenceNumber, false /* isTailBatchInput */);
+        updateBatchInput(batchPointers, sequenceNumber, false);
     }
 
     /**
      * Cancel a batch input.
-     *
+     * <p>
      * Note that as opposed to updateTailBatchInput, we do the UI side of this immediately on the
      * same thread, rather than get this to call a method in LatinIME. This is because
      * canceling a batch input does not necessitate the long operation of pulling suggestions.
@@ -187,7 +178,7 @@ class InputLogicHandler implements Handler.Callback {
 
     /**
      * Trigger an update for a tail batch input.
-     *
+     * <p>
      * A tail batch input is the last update for a gesture, the one that is triggered after the
      * user lifts their finger. This method schedules fetching suggestions on the non-UI thread,
      * then when the suggestions are computed it comes back on the UI thread to update the
@@ -199,7 +190,7 @@ class InputLogicHandler implements Handler.Callback {
     // Called on the UI thread by InputLogic.
     public void updateTailBatchInput(final InputPointers batchPointers,
             final int sequenceNumber) {
-        updateBatchInput(batchPointers, sequenceNumber, true /* isTailBatchInput */);
+        updateBatchInput(batchPointers, sequenceNumber, true);
     }
 
     public void getSuggestedWords(final int inputStyle, final int sequenceNumber,

app/src/main/java/helium314/keyboard/latin/makedict/WordProperty.java

@@ -6,6 +6,7 @@
 
 package helium314.keyboard.latin.makedict;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import com.android.inputmethod.latin.BinaryDictionary;
@@ -20,7 +21,7 @@ import java.util.Arrays;
 
 /**
  * Utility class for a word with a probability.
- *
+ * <p>
  * This is chiefly used to iterate a dictionary.
  */
 public final class WordProperty implements Comparable<WordProperty> {
@@ -150,7 +151,7 @@ public final class WordProperty implements Comparable<WordProperty> {
 
     /**
      * Three-way comparison.
-     *
+     * <p>
      * A Word x is greater than a word y if x has a higher frequency. If they have the same
      * frequency, they are sorted in lexicographic order.
      */
@@ -163,15 +164,14 @@ public final class WordProperty implements Comparable<WordProperty> {
 
     /**
      * Equality test.
-     *
+     * <p>
      * Words are equal if they have the same frequency, the same spellings, and the same
      * attributes.
      */
     @Override
     public boolean equals(Object o) {
         if (o == this) return true;
-        if (!(o instanceof WordProperty)) return false;
+        if (!(o instanceof WordProperty w)) return false;
-        WordProperty w = (WordProperty)o;
         return mProbabilityInfo.equals(w.mProbabilityInfo) && mWord.equals(w.mWord)
                 && mShortcutTargets.equals(w.mShortcutTargets) && equals(mNgrams, w.mNgrams)
                 && mIsNotAWord == w.mIsNotAWord && mIsPossiblyOffensive == w.mIsPossiblyOffensive
@@ -199,7 +199,7 @@ public final class WordProperty implements Comparable<WordProperty> {
     }
 
     @Override
-    public String toString() {
+    @NonNull public String toString() {
         return CombinedFormatUtils.formatWordProperty(this);
     }
 }

app/src/main/java/helium314/keyboard/latin/permissions/PermissionsActivity.java

@@ -57,7 +57,7 @@ public final class PermissionsActivity
     }
 
     @Override
-    protected void onSaveInstanceState(Bundle outState) {
+    protected void onSaveInstanceState(@NonNull Bundle outState) {
         super.onSaveInstanceState(outState);
         outState.putInt(EXTRA_PERMISSION_REQUEST_CODE, mPendingRequestCode);
     }
@@ -68,8 +68,8 @@ public final class PermissionsActivity
         // Only do request when there is no pending request to avoid duplicated requests.
         if (mPendingRequestCode == INVALID_REQUEST_CODE) {
             final Bundle extras = getIntent().getExtras();
-            final String[] permissionsToRequest =
+            if (extras == null) return;
-                    extras.getStringArray(EXTRA_PERMISSION_REQUESTED_PERMISSIONS);
+            final String[] permissionsToRequest = extras.getStringArray(EXTRA_PERMISSION_REQUESTED_PERMISSIONS);
             mPendingRequestCode = extras.getInt(EXTRA_PERMISSION_REQUEST_CODE);
             // Assuming that all supplied permissions are not granted yet, so that we don't need to
             // check them again.

app/src/main/java/helium314/keyboard/latin/settings/AdvancedSettingsFragment.kt

@@ -73,6 +73,7 @@ import java.util.zip.ZipOutputStream
  * - Improve keyboard
  * - Debug settings
  */
+@Suppress("KotlinConstantConditions") // build type might be a constant, but depends on... build type!
 class AdvancedSettingsFragment : SubScreenFragment() {
     private val libfile by lazy { File(requireContext().filesDir.absolutePath + File.separator + JniUtils.JNI_LIB_IMPORT_FILE_NAME) }
     private val backupFilePatterns by lazy { listOf(
@@ -436,8 +437,8 @@ class AdvancedSettingsFragment : SubScreenFragment() {
         }
         checkVersionUpgrade(requireContext())
         Settings.getInstance().startListener()
-        val additionalSubtypes = Settings.readPrefAdditionalSubtypes(sharedPreferences, resources);
+        val additionalSubtypes = Settings.readPrefAdditionalSubtypes(sharedPreferences, resources)
-        updateAdditionalSubtypes(AdditionalSubtypeUtils.createAdditionalSubtypesArray(additionalSubtypes));
+        updateAdditionalSubtypes(AdditionalSubtypeUtils.createAdditionalSubtypesArray(additionalSubtypes))
         reloadEnabledSubtypes(requireContext())
         val newDictBroadcast = Intent(DictionaryPackConstants.NEW_DICTIONARY_INTENT_ACTION)
         activity?.sendBroadcast(newDictBroadcast)

app/src/main/java/helium314/keyboard/latin/setup/SetupStartIndicatorView.java

@@ -21,7 +21,6 @@ import helium314.keyboard.latin.R;
 import androidx.annotation.NonNull;
 import androidx.appcompat.content.res.AppCompatResources;
 import androidx.appcompat.widget.AppCompatTextView;
-import androidx.core.view.ViewCompat;
 
 public final class SetupStartIndicatorView extends LinearLayout {
     public SetupStartIndicatorView(final Context context, final AttributeSet attrs) {
@@ -72,13 +71,13 @@ public final class SetupStartIndicatorView extends LinearLayout {
         @Override
         protected void onDraw(@NonNull final Canvas canvas) {
             super.onDraw(canvas);
-            final int layoutDirection = ViewCompat.getLayoutDirection(this);
+            final int layoutDirection = getLayoutDirection();
             final int width = getWidth();
             final int height = getHeight();
             final float halfHeight = height / 2.0f;
             final Path path = mIndicatorPath;
             path.rewind();
-            if (layoutDirection == ViewCompat.LAYOUT_DIRECTION_RTL) {
+            if (layoutDirection == View.LAYOUT_DIRECTION_RTL) {
                 // Left arrow
                 path.moveTo(width, 0.0f);
                 path.lineTo(0.0f, halfHeight);

app/src/main/java/helium314/keyboard/latin/setup/SetupStepIndicatorView.java

@@ -13,9 +13,9 @@ import android.graphics.Path;
 import android.util.AttributeSet;
 import android.view.View;
 
-import helium314.keyboard.latin.R;
+import androidx.annotation.NonNull;
 
-import androidx.core.view.ViewCompat;
+import helium314.keyboard.latin.R;
 
 public final class SetupStepIndicatorView extends View {
     private final Path mIndicatorPath = new Path();
@@ -29,17 +29,17 @@ public final class SetupStepIndicatorView extends View {
     }
 
     public void setIndicatorPosition(final int stepPos, final int totalStepNum) {
-        final int layoutDirection = ViewCompat.getLayoutDirection(this);
+        final int layoutDirection = getLayoutDirection();
         // The indicator position is the center of the partition that is equally divided into
         // the total step number.
         final float partionWidth = 1.0f / totalStepNum;
         final float pos = stepPos * partionWidth + partionWidth / 2.0f;
-        mXRatio = (layoutDirection == ViewCompat.LAYOUT_DIRECTION_RTL) ? 1.0f - pos : pos;
+        mXRatio = (layoutDirection == View.LAYOUT_DIRECTION_RTL) ? 1.0f - pos : pos;
         invalidate();
     }
 
     @Override
-    protected void onDraw(final Canvas canvas) {
+    protected void onDraw(@NonNull final Canvas canvas) {
         super.onDraw(canvas);
         final int xPos = (int)(getWidth() * mXRatio);
         final int height = getHeight();

app/src/main/java/helium314/keyboard/latin/suggestions/MoreSuggestions.java

@@ -7,10 +7,12 @@
 package helium314.keyboard.latin.suggestions;
 
 import android.content.Context;
-import android.content.res.Resources;
 import android.graphics.Paint;
 import android.graphics.drawable.Drawable;
 
+import androidx.annotation.NonNull;
+import androidx.core.content.ContextCompat;
+
 import helium314.keyboard.keyboard.Key;
 import helium314.keyboard.keyboard.Keyboard;
 import helium314.keyboard.keyboard.internal.KeyboardBuilder;
@@ -45,12 +47,11 @@ public final class MoreSuggestions extends Keyboard {
 
         public int layout(final SuggestedWords suggestedWords, final int fromIndex,
                 final int maxWidth, final int minWidth, final int maxRow, final Paint paint,
-                final Resources res) {
+                final Context context) {
             clearKeys();
-            mDivider = res.getDrawable(R.drawable.more_suggestions_divider);
+            mDivider = ContextCompat.getDrawable(context, R.drawable.more_suggestions_divider);
-            mDividerWidth = mDivider.getIntrinsicWidth();
+            mDividerWidth = mDivider == null ? 0 : mDivider.getIntrinsicWidth();
-            final float padding = res.getDimension(
+            final float padding = context.getResources().getDimension(R.dimen.config_more_suggestions_key_horizontal_padding);
-                    R.dimen.config_more_suggestions_key_horizontal_padding);
 
             int row = 0;
             int index = fromIndex;
@@ -186,7 +187,7 @@ public final class MoreSuggestions extends Keyboard {
             mParams.mVerticalGap = mParams.mTopPadding = parentKeyboard.mVerticalGap / 2;
             mPaneView.updateKeyboardGeometry(mParams.mDefaultAbsoluteRowHeight);
             final int count = mParams.layout(suggestedWords, fromIndex, maxWidth, minWidth, maxRow,
-                    mPaneView.newLabelPaint(null /* key */), mResources);
+                    mPaneView.newLabelPaint(null /* key */), getMContext());
             mFromIndex = fromIndex;
             mToIndex = fromIndex + count;
             mSuggestedWords = suggestedWords;
@@ -194,7 +195,7 @@ public final class MoreSuggestions extends Keyboard {
         }
 
         @Override
-        public MoreSuggestions build() {
+        @NonNull public MoreSuggestions build() {
             final MoreSuggestionsParam params = mParams;
             for (int index = mFromIndex; index < mToIndex; index++) {
                 final int x = params.getX(index);

app/src/main/java/helium314/keyboard/latin/suggestions/SuggestionStripView.java

@@ -67,8 +67,8 @@ import java.util.ArrayList;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.appcompat.widget.PopupMenu;
-import androidx.core.view.ViewCompat;
 
 public final class SuggestionStripView extends RelativeLayout implements OnClickListener,
         OnLongClickListener {
@@ -76,7 +76,6 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
         void pickSuggestionManually(SuggestedWordInfo word);
         void onCodeInput(int primaryCode, int x, int y, boolean isKeyRepeat);
         void removeSuggestion(final String word);
-        CharSequence getSelection();
     }
 
     public static boolean DEBUG_SUGGESTIONS;
@@ -124,8 +123,8 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
         }
 
         public void setLayoutDirection(final int layoutDirection) {
-            ViewCompat.setLayoutDirection(mSuggestionStripView, layoutDirection);
+            mSuggestionStripView.setLayoutDirection(layoutDirection);
-            ViewCompat.setLayoutDirection(mSuggestionsStrip, layoutDirection);
+            mSuggestionsStrip.setLayoutDirection(layoutDirection);
         }
 
         public void showSuggestionsStrip() {
@@ -141,6 +140,7 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
         this(context, attrs, R.attr.suggestionStripViewStyle);
     }
 
+    @SuppressLint("InflateParams") // does not seem suitable here
     public SuggestionStripView(final Context context, final AttributeSet attrs, final int defStyle) {
         super(context, attrs, defStyle);
         final Colors colors = Settings.getInstance().getCurrent().mColors;
@@ -183,6 +183,7 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
                 R.dimen.config_more_suggestions_modal_tolerance);
         mMoreSuggestionsSlidingDetector = new GestureDetector(context, mMoreSuggestionsSlidingListener);
 
+        @SuppressLint("CustomViewStyleable")
         final TypedArray keyboardAttr = context.obtainStyledAttributes(attrs, R.styleable.Keyboard, defStyle, R.style.SuggestionStripView);
         mIncognitoIcon = keyboardAttr.getDrawable(R.styleable.Keyboard_iconIncognitoKey);
         mToolbarArrowIcon = keyboardAttr.getDrawable(R.styleable.Keyboard_iconToolbarKey);
@@ -262,9 +263,9 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
     public void setRtl(final boolean isRtlLanguage) {
         final int layoutDirection;
         if (!Settings.getInstance().getCurrent().mVarToolbarDirection)
-            layoutDirection = ViewCompat.LAYOUT_DIRECTION_LOCALE;
+            layoutDirection = View.LAYOUT_DIRECTION_LOCALE;
         else{
-            layoutDirection = isRtlLanguage ? ViewCompat.LAYOUT_DIRECTION_RTL : ViewCompat.LAYOUT_DIRECTION_LTR;
+            layoutDirection = isRtlLanguage ? View.LAYOUT_DIRECTION_RTL : View.LAYOUT_DIRECTION_LTR;
             mRtl = isRtlLanguage ? -1 : 1;
         }
         mStripVisibilityGroup.setLayoutDirection(layoutDirection);
@@ -528,7 +529,8 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
     private final GestureDetector.OnGestureListener mMoreSuggestionsSlidingListener =
             new GestureDetector.SimpleOnGestureListener() {
         @Override
-        public boolean onScroll(MotionEvent down, MotionEvent me, float deltaX, float deltaY) {
+        public boolean onScroll(@Nullable MotionEvent down, @NonNull MotionEvent me, float deltaX, float deltaY) {
+            if (down == null) return false;
             final float dy = me.getY() - down.getY();
             if (mToolbarContainer.getVisibility() != VISIBLE && deltaY > 0 && dy < 0) {
                 return showMoreSuggestions();
@@ -637,7 +639,7 @@ public final class SuggestionStripView extends RelativeLayout implements OnClick
         AudioAndHapticFeedbackManager.getInstance().performHapticAndAudioFeedback(KeyCode.NOT_SPECIFIED, this);
         final Object tag = view.getTag();
         if (tag instanceof ToolbarKey) {
-            final Integer code = getCodeForToolbarKey((ToolbarKey) tag);
+            final int code = getCodeForToolbarKey((ToolbarKey) tag);
             if (code != KeyCode.UNSPECIFIED) {
                 Log.d(TAG, "click toolbar key "+tag);
                 mListener.onCodeInput(code, Constants.SUGGESTION_STRIP_COORDINATE, Constants.SUGGESTION_STRIP_COORDINATE, false);

app/src/main/java/helium314/keyboard/latin/utils/CustomLayoutUtils.kt

@@ -18,7 +18,6 @@ import helium314.keyboard.keyboard.internal.keyboard_parser.RawKeyboardParser
 import helium314.keyboard.keyboard.internal.keyboard_parser.addLocaleKeyTextsToParams
 import helium314.keyboard.latin.R
 import helium314.keyboard.latin.common.FileUtils
-import helium314.keyboard.latin.settings.Settings
 import java.io.File
 import java.io.IOException
 import java.math.BigInteger
@@ -80,13 +79,13 @@ private fun checkLayout(layoutContent: String, context: Context): Boolean? {
     params.mPopupKeyTypes.add(POPUP_KEYS_LAYOUT)
     addLocaleKeyTextsToParams(context, params, POPUP_KEYS_NORMAL)
     try {
-        val keys = RawKeyboardParser.parseJsonString(layoutContent).map { it.mapNotNull { it.compute(params)?.toKeyParams(params) } }
+        val keys = RawKeyboardParser.parseJsonString(layoutContent).map { row -> row.mapNotNull { it.compute(params)?.toKeyParams(params) } }
         if (!checkKeys(keys))
             return null
         return true
     } catch (e: Exception) { Log.w(TAG, "error parsing custom json layout", e) }
     try {
-        val keys = RawKeyboardParser.parseSimpleString(layoutContent).map { it.map { it.toKeyParams(params) } }
+        val keys = RawKeyboardParser.parseSimpleString(layoutContent).map { row -> row.map { it.toKeyParams(params) } }
         if (!checkKeys(keys))
             return null
         return false
@@ -94,7 +93,7 @@ private fun checkLayout(layoutContent: String, context: Context): Boolean? {
     if (layoutContent.startsWith("[")) {
         // layout can't be loaded, assume it's json -> load json layout again because the error message shown to the user is from the most recent error
         try {
-            RawKeyboardParser.parseJsonString(layoutContent).map { it.mapNotNull { it.compute(params)?.toKeyParams(params) } }
+            RawKeyboardParser.parseJsonString(layoutContent).map { row -> row.mapNotNull { it.compute(params)?.toKeyParams(params) } }
         } catch (e: Exception) { Log.w(TAG, "error parsing custom json layout", e) }
     }
     return null
@@ -109,19 +108,19 @@ private fun checkKeys(keys: List<List<Key.KeyParams>>): Boolean {
         Log.w(TAG, "too many rows")
         return false
     }
-    if (keys.any { it.size > 20 }) {
+    if (keys.any { row -> row.size > 20 }) {
         Log.w(TAG, "too many keys in one row")
         return false
     }
-    if (keys.any { it.any { ((it.mLabel?.length ?: 0) > 6) } }) {
+    if (keys.any { row -> row.any { ((it.mLabel?.length ?: 0) > 6) } }) {
         Log.w(TAG, "too long text on key")
         return false
     }
-    if (keys.any { it.any { (it.mPopupKeys?.size ?: 0) > 20 } }) {
+    if (keys.any { row -> row.any { (it.mPopupKeys?.size ?: 0) > 20 } }) {
         Log.w(TAG, "too many popup keys on a key")
         return false
     }
-    if (keys.any { it.any { it.mPopupKeys?.any { (it.mLabel?.length ?: 0) > 10 } == true } }) {
+    if (keys.any { row -> row.any { it.mPopupKeys?.any { popupKey -> (popupKey.mLabel?.length ?: 0) > 10 } == true } }) {
         Log.w(TAG, "too long text on popup key")
         return false
     }

app/src/main/java/helium314/keyboard/latin/utils/RecapitalizeStatus.java

@@ -29,7 +29,7 @@ public class RecapitalizeStatus {
         CAPS_MODE_ALL_UPPER
     };
 
-    private static final int getStringMode(final String string, final int[] sortedSeparators) {
+    private static int getStringMode(final String string, final int[] sortedSeparators) {
         if (StringUtils.isIdenticalAfterUpcase(string)) {
             return CAPS_MODE_ALL_UPPER;
         } else if (StringUtils.isIdenticalAfterDowncase(string)) {
@@ -42,14 +42,14 @@ public class RecapitalizeStatus {
     }
 
     public static String modeToString(final int recapitalizeMode) {
-        switch (recapitalizeMode) {
+        return switch (recapitalizeMode) {
-        case NOT_A_RECAPITALIZE_MODE: return "undefined";
+            case NOT_A_RECAPITALIZE_MODE -> "undefined";
-        case CAPS_MODE_ORIGINAL_MIXED_CASE: return "mixedCase";
+            case CAPS_MODE_ORIGINAL_MIXED_CASE -> "mixedCase";
-        case CAPS_MODE_ALL_LOWER: return "allLower";
+            case CAPS_MODE_ALL_LOWER -> "allLower";
-        case CAPS_MODE_FIRST_WORD_UPPER: return "firstWordUpper";
+            case CAPS_MODE_FIRST_WORD_UPPER -> "firstWordUpper";
-        case CAPS_MODE_ALL_UPPER: return "allUpper";
+            case CAPS_MODE_ALL_UPPER -> "allUpper";
-        default: return "unknown<" + recapitalizeMode + ">";
+            default -> "unknown<" + recapitalizeMode + ">";
-        }
+        };
     }
 
     /**
@@ -145,21 +145,10 @@ public class RecapitalizeStatus {
             }
             ++count;
             switch (ROTATION_STYLE[mRotationStyleCurrentIndex]) {
-            case CAPS_MODE_ORIGINAL_MIXED_CASE:
+                case CAPS_MODE_ALL_LOWER -> mStringAfter = mStringBefore.toLowerCase(mLocale);
-                mStringAfter = mStringBefore;
+                case CAPS_MODE_FIRST_WORD_UPPER -> mStringAfter = StringUtils.capitalizeEachWord(mStringBefore, mSortedSeparators, mLocale);
-                break;
+                case CAPS_MODE_ALL_UPPER -> mStringAfter = mStringBefore.toUpperCase(mLocale);
-            case CAPS_MODE_ALL_LOWER:
+                default -> mStringAfter = mStringBefore;
-                mStringAfter = mStringBefore.toLowerCase(mLocale);
-                break;
-            case CAPS_MODE_FIRST_WORD_UPPER:
-                mStringAfter = StringUtils.capitalizeEachWord(mStringBefore, mSortedSeparators,
-                        mLocale);
-                break;
-            case CAPS_MODE_ALL_UPPER:
-                mStringAfter = mStringBefore.toUpperCase(mLocale);
-                break;
-            default:
-                mStringAfter = mStringBefore;
             }
         } while (mStringAfter.equals(oldResult) && count < ROTATION_STYLE.length + 1);
         mCursorEndAfter = mCursorStartAfter + mStringAfter.length();

app/src/test/java/helium314/keyboard/KeySpecParserTest.kt

@@ -2,7 +2,6 @@ package helium314.keyboard
 
 import helium314.keyboard.keyboard.internal.KeySpecParser
 import helium314.keyboard.keyboard.internal.keyboard_parser.floris.KeyCode
-import helium314.keyboard.latin.common.Constants
 import org.junit.Assert.assertEquals
 import org.junit.Test
 

app/src/test/java/helium314/keyboard/latin/InputLogicTest.kt

@@ -867,7 +867,7 @@ private val ic = object : InputConnection {
         // update selection
         selectionStart -= beforeLength
         selectionEnd -= beforeLength
-        return true;
+        return true
     }
     override fun sendKeyEvent(p0: KeyEvent): Boolean {
         if (p0.action != KeyEvent.ACTION_DOWN) return true // only change the text on key down, like RichInputConnection does
@@ -908,7 +908,7 @@ private val ic = object : InputConnection {
     override fun clearMetaKeyStates(p0: Int): Boolean = TODO("Not yet implemented")
     override fun reportFullscreenMode(p0: Boolean): Boolean = TODO("Not yet implemented")
     override fun performPrivateCommand(p0: String?, p1: Bundle?): Boolean = TODO("Not yet implemented")
-    override fun getHandler(): Handler? = TODO("Not yet implemented")
+    override fun getHandler(): Handler = TODO("Not yet implemented")
     override fun closeConnection() = TODO("Not yet implemented")
     override fun commitContent(p0: InputContentInfo, p1: Int, p2: Bundle?): Boolean = TODO("Not yet implemented")
 }

app/src/test/java/helium314/keyboard/latin/SuggestTest.kt

@@ -25,6 +25,7 @@ import org.robolectric.annotation.Implements
 import org.robolectric.shadows.ShadowLog
 import java.util.*
 
+@Suppress("NonAsciiCharacters")
 @RunWith(RobolectricTestRunner::class)
 @Config(shadows = [
     ShadowLocaleManagerCompat::class,

build.gradle

@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.9.23'
+    ext.kotlin_version = '1.9.24'
     repositories {
         mavenCentral()
         google()
@@ -17,7 +17,7 @@ buildscript {
 }
 
 plugins {
-    id 'org.jetbrains.kotlin.plugin.serialization' version '1.9.23' apply false
+    id 'org.jetbrains.kotlin.plugin.serialization' version "$kotlin_version"
 }
 
 allprojects {