Implemented continuous scrolling for emoji keyboards

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/DynamicGridKeyboard.java

@@ -76,6 +76,15 @@ final class DynamicGridKeyboard extends Keyboard {
         throw new RuntimeException("Can't find template key: code=" + code);
     }
 
+    public int getDynamicOccupiedHeight() {
+        final int row = (mGridKeys.size() - 1) / mColumnsNum + 1;
+        return row * mVerticalStep;
+    }
+
+    public int getColumnsCount() {
+        return mColumnsNum;
+    }
+
     public void addPendingKey(final Key usedKey) {
         synchronized (mLock) {
             mPendingKeys.addLast(usedKey);

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiCategory.java

@@ -21,9 +21,7 @@ import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.graphics.Paint;
 import android.graphics.Rect;
-import android.os.Build;
 import android.util.Log;
-import android.util.Pair;
 
 import androidx.core.graphics.PaintCompat;
 import org.dslul.openboard.inputmethod.keyboard.Key;
@@ -56,6 +54,8 @@ final class EmojiCategory {
     private static final int ID_FLAGS = 9;
     private static final int ID_EMOTICONS = 10;
 
+    private static final int MAX_LINE_COUNT_PER_PAGE = 3;
+
     public final class CategoryProperties {
         public final int mCategoryId;
         public final int mPageCount;
@@ -119,7 +119,7 @@ final class EmojiCategory {
 
     private final SharedPreferences mPrefs;
     private final Resources mRes;
-    private final int mMaxPageKeyCount;
+    private final int mMaxRecentsKeyCount;
     private final KeyboardLayoutSet mLayoutSet;
     private final HashMap<String, Integer> mCategoryNameToIdMap = new HashMap<>();
     private final int[] mCategoryTabIconId = new int[sCategoryName.length];
@@ -134,7 +134,7 @@ final class EmojiCategory {
             final KeyboardLayoutSet layoutSet, final TypedArray emojiPaletteViewAttr) {
         mPrefs = prefs;
         mRes = res;
-        mMaxPageKeyCount = res.getInteger(R.integer.config_emoji_keyboard_max_page_key_count);
+        mMaxRecentsKeyCount = res.getInteger(R.integer.config_emoji_keyboard_max_recents_key_count);
         mLayoutSet = layoutSet;
         for (int i = 0; i < sCategoryName.length; ++i) {
             mCategoryNameToIdMap.put(sCategoryName[i], i);
@@ -170,7 +170,7 @@ final class EmojiCategory {
             mCurrentCategoryId = defaultCategoryId;
         }
 
-        if (mCurrentCategoryPageId >= getCategoryPageCount(mCurrentCategoryId)) {
+        if (mCurrentCategoryPageId >= computeCategoryPageCount(mCurrentCategoryId)) {
             mCurrentCategoryPageId = 0;
         }
     }
@@ -179,7 +179,7 @@ final class EmojiCategory {
         // Load a keyboard of categoryId
         getKeyboard(categoryId, 0 /* categoryPageId */);
         final CategoryProperties properties =
-                new CategoryProperties(categoryId, getCategoryPageCount(categoryId));
+                new CategoryProperties(categoryId, computeCategoryPageCount(categoryId));
         mShownCategories.add(properties);
     }
 
@@ -217,11 +217,11 @@ final class EmojiCategory {
         return mCurrentCategoryId;
     }
 
-    public int getCurrentCategoryPageSize() {
+    public int getCurrentCategoryPageCount() {
-        return getCategoryPageSize(mCurrentCategoryId);
+        return getCategoryPageCount(mCurrentCategoryId);
     }
 
-    public int getCategoryPageSize(final int categoryId) {
+    public int getCategoryPageCount(final int categoryId) {
         for (final CategoryProperties prop : mShownCategories) {
             if (prop.mCategoryId == categoryId) {
                 return prop.mPageCount;
@@ -283,38 +283,21 @@ final class EmojiCategory {
         return getTabIdFromCategoryId(EmojiCategory.ID_RECENTS);
     }
 
-    private int getCategoryPageCount(final int categoryId) {
+    private int computeCategoryPageCount(final int categoryId) {
         final Keyboard keyboard = mLayoutSet.getKeyboard(sCategoryElementId[categoryId]);
-        return (keyboard.getSortedKeys().size() - 1) / mMaxPageKeyCount + 1;
+        return (keyboard.getSortedKeys().size() - 1) / computeMaxKeyCountPerPage() + 1;
     }
 
-    // Returns a pair of the category id and the category page id from the view pager's page
+    // Returns a keyboard from the recycler view's adapter position.
-    // position. The category page id is numbered in each category. And the view page position
+    public DynamicGridKeyboard getKeyboardFromAdapterPosition(final int position) {
-    // is the position of the current shown page in the view pager which contains all pages of
+        if (position >= 0 && position < getCurrentCategoryPageCount()) {
-    // all categories.
+            return getKeyboard(mCurrentCategoryId, position);
-    public Pair<Integer, Integer> getCategoryIdAndPageIdFromPagePosition(final int position) {
-        int sum = 0;
-        for (final CategoryProperties properties : mShownCategories) {
-            final int temp = sum;
-            sum += properties.mPageCount;
-            if (sum > position) {
-                return new Pair<>(properties.mCategoryId, position - temp);
-            }
         }
+        Log.w(TAG, "invalid position for categoryId : " + mCurrentCategoryId);
         return null;
     }
 
-    // Returns a keyboard from the view pager's page position.
+    private static Long getCategoryKeyboardMapKey(final int categoryId, final int id) {
-    public DynamicGridKeyboard getKeyboardFromPagePosition(final int position) {
-        final Pair<Integer, Integer> categoryAndId =
-                getCategoryIdAndPageIdFromPagePosition(position);
-        if (categoryAndId != null) {
-            return getKeyboard(categoryAndId.first, categoryAndId.second);
-        }
-        return null;
-    }
-
-    private static final Long getCategoryKeyboardMapKey(final int categoryId, final int id) {
         return (((long) categoryId) << Integer.SIZE) | id;
     }
 
@@ -328,19 +311,20 @@ final class EmojiCategory {
             if (categoryId == EmojiCategory.ID_RECENTS) {
                 final DynamicGridKeyboard kbd = new DynamicGridKeyboard(mPrefs,
                         mLayoutSet.getKeyboard(KeyboardId.ELEMENT_EMOJI_RECENTS),
-                        mMaxPageKeyCount, categoryId);
+                        mMaxRecentsKeyCount, categoryId);
                 mCategoryKeyboardMap.put(categoryKeyboardMapKey, kbd);
                 return kbd;
             }
 
             final Keyboard keyboard = mLayoutSet.getKeyboard(sCategoryElementId[categoryId]);
-            final Key[][] sortedKeys = sortKeysIntoPages(
+            final int keyCountPerPage = computeMaxKeyCountPerPage();
-                    keyboard.getSortedKeys(), mMaxPageKeyCount);
+            final Key[][] sortedKeysPages = sortKeysGrouped(
-            for (int pageId = 0; pageId < sortedKeys.length; ++pageId) {
+                    keyboard.getSortedKeys(), keyCountPerPage);
+            for (int pageId = 0; pageId < sortedKeysPages.length; ++pageId) {
                 final DynamicGridKeyboard tempKeyboard = new DynamicGridKeyboard(mPrefs,
                         mLayoutSet.getKeyboard(KeyboardId.ELEMENT_EMOJI_RECENTS),
-                        mMaxPageKeyCount, categoryId);
+                        keyCountPerPage, categoryId);
-                for (final Key emojiKey : sortedKeys[pageId]) {
+                for (final Key emojiKey : sortedKeysPages[pageId]) {
                     if (emojiKey == null) {
                         break;
                     }
@@ -353,37 +337,33 @@ final class EmojiCategory {
         }
     }
 
-    public int getTotalPageCountOfAllCategories() {
+    private int computeMaxKeyCountPerPage() {
-        int sum = 0;
+        final DynamicGridKeyboard tempKeyboard = new DynamicGridKeyboard(mPrefs,
-        for (CategoryProperties properties : mShownCategories) {
+                mLayoutSet.getKeyboard(KeyboardId.ELEMENT_EMOJI_RECENTS),
-            sum += properties.mPageCount;
+                0, 0);
-        }
+        return MAX_LINE_COUNT_PER_PAGE * tempKeyboard.getColumnsCount();
-        return sum;
     }
 
-    private static Comparator<Key> EMOJI_KEY_COMPARATOR = new Comparator<Key>() {
+    private static final Comparator<Key> EMOJI_KEY_COMPARATOR = (lhs, rhs) -> {
-        @Override
+        final Rect lHitBox = lhs.getHitBox();
-        public int compare(final Key lhs, final Key rhs) {
+        final Rect rHitBox = rhs.getHitBox();
-            final Rect lHitBox = lhs.getHitBox();
+        if (lHitBox.top < rHitBox.top) {
-            final Rect rHitBox = rhs.getHitBox();
+            return -1;
-            if (lHitBox.top < rHitBox.top) {
+        } else if (lHitBox.top > rHitBox.top) {
-                return -1;
+            return 1;
-            } else if (lHitBox.top > rHitBox.top) {
-                return 1;
-            }
-            if (lHitBox.left < rHitBox.left) {
-                return -1;
-            } else if (lHitBox.left > rHitBox.left) {
-                return 1;
-            }
-            if (lhs.getCode() == rhs.getCode()) {
-                return 0;
-            }
-            return lhs.getCode() < rhs.getCode() ? -1 : 1;
         }
+        if (lHitBox.left < rHitBox.left) {
+            return -1;
+        } else if (lHitBox.left > rHitBox.left) {
+            return 1;
+        }
+        if (lhs.getCode() == rhs.getCode()) {
+            return 0;
+        }
+        return lhs.getCode() < rhs.getCode() ? -1 : 1;
     };
 
-    private static Key[][] sortKeysIntoPages(final List<Key> inKeys, final int maxPageCount) {
+    private static Key[][] sortKeysGrouped(final List<Key> inKeys, final int maxPageCount) {
         final ArrayList<Key> keys = new ArrayList<>(inKeys);
         Collections.sort(keys, EMOJI_KEY_COMPARATOR);
         final int pageCount = (keys.size() - 1) / maxPageCount + 1;

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiCategoryPageIndicatorView.java

@@ -61,9 +61,9 @@ public final class EmojiCategoryPageIndicatorView extends View {
         final float height = getHeight();
         final float width = getWidth();
         final float unitWidth = width / mCategoryPageSize;
-        final float left = unitWidth * mCurrentCategoryPageId + mOffset * unitWidth;
+        final float left = Math.min(unitWidth * mCurrentCategoryPageId + mOffset * unitWidth, width - unitWidth);
         final float top = 0.0f;
-        final float right = left + unitWidth;
+        final float right = Math.min(left + unitWidth, width);
         final float bottom = height * BOTTOM_MARGIN_RATIO;
         canvas.drawRect(left, top, right, bottom, mPaint);
     }

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiLayoutParams.java

@@ -20,17 +20,16 @@ import android.content.res.Resources;
 import android.view.View;
 import android.widget.LinearLayout;
 
+import androidx.recyclerview.widget.RecyclerView;
 import org.dslul.openboard.inputmethod.latin.R;
+import org.dslul.openboard.inputmethod.latin.settings.SettingsValues;
 import org.dslul.openboard.inputmethod.latin.utils.ResourceUtils;
 
-import androidx.viewpager.widget.ViewPager;
-import androidx.viewpager2.widget.ViewPager2;
-
 final class EmojiLayoutParams {
     private static final int DEFAULT_KEYBOARD_ROWS = 4;
 
-    public final int mEmojiPagerHeight;
+    public final int mEmojiListHeight;
-    private final int mEmojiPagerBottomMargin;
+    private final int mEmojiListBottomMargin;
     public final int mEmojiKeyboardHeight;
     private final int mEmojiCategoryPageIdViewHeight;
     public final int mEmojiActionBarHeight;
@@ -56,16 +55,16 @@ final class EmojiLayoutParams {
                 + mKeyVerticalGap;
         mEmojiActionBarHeight = baseheight / DEFAULT_KEYBOARD_ROWS
                 - (mKeyVerticalGap - mBottomPadding) / 2;
-        mEmojiPagerHeight = defaultKeyboardHeight - mEmojiActionBarHeight
+        mEmojiListHeight = defaultKeyboardHeight - mEmojiActionBarHeight
                 - mEmojiCategoryPageIdViewHeight;
-        mEmojiPagerBottomMargin = 0;
+        mEmojiListBottomMargin = 0;
-        mEmojiKeyboardHeight = mEmojiPagerHeight - mEmojiPagerBottomMargin - 1;
+        mEmojiKeyboardHeight = mEmojiListHeight - mEmojiListBottomMargin - 1;
     }
 
-    public void setPagerProperties(final ViewPager2 vp) {
+    public void setEmojiListProperties(final RecyclerView vp) {
         final LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) vp.getLayoutParams();
         lp.height = mEmojiKeyboardHeight;
-        lp.bottomMargin = mEmojiPagerBottomMargin;
+        lp.bottomMargin = mEmojiListBottomMargin;
         vp.setLayoutParams(lp);
     }
 

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiPageKeyboardView.java

@@ -113,6 +113,20 @@ final class EmojiPageKeyboardView extends KeyboardView implements
         mMoreKeysKeyboardContainer = inflater.inflate(moreKeysKeyboardLayoutId, null);
     }
 
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        final Keyboard keyboard = getKeyboard();
+        if (keyboard instanceof DynamicGridKeyboard) {
+            final int width = keyboard.mOccupiedWidth + getPaddingLeft() + getPaddingRight();
+            final int occupiedHeight =
+                    ((DynamicGridKeyboard) keyboard).getDynamicOccupiedHeight();
+            final int height = occupiedHeight + getPaddingTop() + getPaddingBottom();
+            setMeasuredDimension(width, height);
+            return;
+        }
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+    }
+
     @Override
     public void setHardwareAcceleratedDrawingEnabled(final boolean enabled) {
         super.setHardwareAcceleratedDrawingEnabled(enabled);
@@ -173,9 +187,7 @@ final class EmojiPageKeyboardView extends KeyboardView implements
         Keyboard moreKeysKeyboard = mMoreKeysKeyboardCache.get(key);
         if (moreKeysKeyboard == null) {
             final MoreKeysKeyboard.Builder builder = new MoreKeysKeyboard.Builder(
-                    getContext(), key, getKeyboard(),
+                    getContext(), key, getKeyboard(), false, 0, 0, newLabelPaint(key));
-                    true, key.getWidth(), key.getHeight(), // TODO This is cheating
-                    newLabelPaint(key));
             moreKeysKeyboard = builder.build();
             mMoreKeysKeyboardCache.put(key, moreKeysKeyboard);
         }
@@ -382,9 +394,6 @@ final class EmojiPageKeyboardView extends KeyboardView implements
         final Runnable pendingKeyDown = mPendingKeyDown;
         final Key currentKey = mCurrentKey;
         releaseCurrentKey(false /* withKeyRegistering */);
-        if (key == null) {
-            return false;
-        }
 
         final boolean isShowingMoreKeysPanel = isShowingMoreKeysPanel();
         if (isShowingMoreKeysPanel) {
@@ -402,7 +411,7 @@ final class EmojiPageKeyboardView extends KeyboardView implements
                     callListenerOnReleaseKey(key, true /* withRegistering */);
                 }
             }, KEY_RELEASE_DELAY_TIME);
-        } else {
+        } else if (key != null) {
             callListenerOnReleaseKey(key, true /* withRegistering */);
         }
 

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiPalettesAdapter.java

@@ -182,7 +182,7 @@ final class EmojiPalettesAdapter extends RecyclerView.Adapter<EmojiPalettesAdapt
             mActiveKeyboardViews.remove(position);
         }
         final Keyboard keyboard =
-                mEmojiCategory.getKeyboardFromPagePosition(position);
+                mEmojiCategory.getKeyboardFromAdapterPosition(position);
         holder.getKeyboardView().setKeyboard(keyboard);
         holder.getKeyboardView().setOnKeyEventListener(mListener);
         //parent.addView(keyboardView);
@@ -201,10 +201,9 @@ final class EmojiPalettesAdapter extends RecyclerView.Adapter<EmojiPalettesAdapt
 
     @Override
     public int getItemCount() {
-        return mEmojiCategory.getTotalPageCountOfAllCategories();
+        return mEmojiCategory.getCurrentCategoryPageCount();
     }
 
-
     static class ViewHolder extends RecyclerView.ViewHolder {
         private EmojiPageKeyboardView customView;
 

app/src/main/java/org/dslul/openboard/inputmethod/keyboard/emoji/EmojiPalettesView.java

@@ -21,7 +21,6 @@ import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.graphics.Color;
 import android.util.AttributeSet;
-import android.util.Pair;
 import android.util.TypedValue;
 import android.view.LayoutInflater;
 import android.view.MotionEvent;
@@ -34,6 +33,9 @@ import android.widget.TabHost.OnTabChangeListener;
 import android.widget.TabWidget;
 import android.widget.TextView;
 
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
 import org.dslul.openboard.inputmethod.compat.TabHostCompat;
 import org.dslul.openboard.inputmethod.keyboard.Key;
 import org.dslul.openboard.inputmethod.keyboard.KeyboardActionListener;
@@ -46,10 +48,12 @@ import org.dslul.openboard.inputmethod.latin.AudioAndHapticFeedbackManager;
 import org.dslul.openboard.inputmethod.latin.R;
 import org.dslul.openboard.inputmethod.latin.RichInputMethodSubtype;
 import org.dslul.openboard.inputmethod.latin.common.Constants;
+import org.dslul.openboard.inputmethod.latin.settings.Settings;
+import org.dslul.openboard.inputmethod.latin.settings.SettingsValues;
 import org.dslul.openboard.inputmethod.latin.utils.DeviceProtectedUtils;
 import org.dslul.openboard.inputmethod.latin.utils.ResourceUtils;
 
-import androidx.viewpager2.widget.ViewPager2;
+import org.jetbrains.annotations.NotNull;
 
 import static org.dslul.openboard.inputmethod.latin.common.Constants.NOT_A_COORDINATE;
 
@@ -78,6 +82,7 @@ public final class EmojiPalettesView extends LinearLayout
     private EmojiPalettesAdapter mEmojiPalettesAdapter;
     private final EmojiLayoutParams mEmojiLayoutParams;
     private final DeleteKeyOnTouchListener mDeleteKeyOnTouchListener;
+    private final LinearLayoutManager mEmojiLayoutManager;
 
     private ImageButton mDeleteKey;
     private TextView mAlphabetKeyLeft;
@@ -85,8 +90,7 @@ public final class EmojiPalettesView extends LinearLayout
     // TODO: Remove this workaround.
     private View mSpacebarIcon;
     private TabHostCompat mTabHost;
-    private ViewPager2 mEmojiPager;
+    private RecyclerView mEmojiRecyclerView;
-    private int mCurrentPagerPosition = 0;
     private EmojiCategoryPageIndicatorView mEmojiCategoryPageIndicatorView;
 
     private KeyboardActionListener mKeyboardActionListener = KeyboardActionListener.EMPTY_LISTENER;
@@ -132,6 +136,7 @@ public final class EmojiPalettesView extends LinearLayout
                 R.styleable.EmojiPalettesView_categoryPageIndicatorBackground, 0);
         emojiPalettesViewAttr.recycle();
         mDeleteKeyOnTouchListener = new DeleteKeyOnTouchListener();
+        mEmojiLayoutManager = new LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false);
     }
 
     @Override
@@ -164,6 +169,7 @@ public final class EmojiPalettesView extends LinearLayout
 
     @Override
     protected void onFinishInflate() {
+        super.onFinishInflate();
         mTabHost = findViewById(R.id.emoji_category_tabhost);
         mTabHost.setup();
         for (final EmojiCategory.CategoryProperties properties
@@ -183,51 +189,41 @@ public final class EmojiPalettesView extends LinearLayout
 
         mEmojiPalettesAdapter = new EmojiPalettesAdapter(mEmojiCategory, this);
 
-        mEmojiPager = findViewById(R.id.emoji_keyboard_pager);
+        mEmojiRecyclerView = findViewById(R.id.emoji_keyboard_list);
-        mEmojiPager.setAdapter(mEmojiPalettesAdapter);
+        mEmojiRecyclerView.setLayoutManager(mEmojiLayoutManager);
-
+        mEmojiRecyclerView.setAdapter(mEmojiPalettesAdapter);
-        mEmojiPager.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
+        mEmojiRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
             @Override
-            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
+            public void onScrollStateChanged(@NonNull @NotNull RecyclerView recyclerView, int newState) {
-                mEmojiPalettesAdapter.onPageScrolled();
+                super.onScrollStateChanged(recyclerView, newState);
-                final Pair<Integer, Integer> newPos =
-                        mEmojiCategory.getCategoryIdAndPageIdFromPagePosition(position);
-                final int newCategoryId = newPos.first;
-                final int newCategorySize = mEmojiCategory.getCategoryPageSize(newCategoryId);
-                final int currentCategoryId = mEmojiCategory.getCurrentCategoryId();
-                final int currentCategoryPageId = mEmojiCategory.getCurrentCategoryPageId();
-                final int currentCategorySize = mEmojiCategory.getCurrentCategoryPageSize();
-                if (newCategoryId == currentCategoryId) {
-                    mEmojiCategoryPageIndicatorView.setCategoryPageId(
-                            newCategorySize, newPos.second, positionOffset);
-                } else if (newCategoryId > currentCategoryId) {
-                    mEmojiCategoryPageIndicatorView.setCategoryPageId(
-                            currentCategorySize, currentCategoryPageId, positionOffset);
-                } else if (newCategoryId < currentCategoryId) {
-                    mEmojiCategoryPageIndicatorView.setCategoryPageId(
-                            currentCategorySize, currentCategoryPageId, positionOffset - 1);
-                }
-            }
-
-            @Override
-            public void onPageSelected(int position) {
-                final Pair<Integer, Integer> newPos =
-                        mEmojiCategory.getCategoryIdAndPageIdFromPagePosition(position);
-                setCurrentCategoryAndPageId(newPos.first /* categoryId */, newPos.second /* categoryPageId */,
-                        false /* force */);
-                updateEmojiCategoryPageIdView();
-                mCurrentPagerPosition = position;
-            }
-
-            @Override
-            public void onPageScrollStateChanged(int state) {
                 // Ignore this message. Only want the actual page selected.
             }
+
+            @Override
+            public void onScrolled(@NonNull @NotNull RecyclerView recyclerView, int dx, int dy) {
+                super.onScrolled(recyclerView, dx, dy);
+                mEmojiPalettesAdapter.onPageScrolled();
+
+                final int offset = recyclerView.computeVerticalScrollOffset();
+                final int extent = recyclerView.computeVerticalScrollExtent();
+                final int range = recyclerView.computeVerticalScrollRange();
+                final float percentage = offset / (float) (range - extent);
+
+                final int currentCategorySize = mEmojiCategory.getCurrentCategoryPageCount();
+                final int a = (int) (percentage * currentCategorySize);
+                final float b = percentage * currentCategorySize - a;
+                mEmojiCategoryPageIndicatorView.setCategoryPageId(
+                        currentCategorySize, a, b);
+
+                final int firstCompleteVisibleBoard = mEmojiLayoutManager.findFirstCompletelyVisibleItemPosition();
+                final int firstVisibleBoard = mEmojiLayoutManager.findFirstVisibleItemPosition();
+                mEmojiCategory.setCurrentCategoryPageId(
+                        firstCompleteVisibleBoard > 0 ? firstCompleteVisibleBoard : firstVisibleBoard);
+            }
         });
 
-        mEmojiPager.setOffscreenPageLimit(ViewPager2.OFFSCREEN_PAGE_LIMIT_DEFAULT);
+        mEmojiRecyclerView.setPersistentDrawingCache(PERSISTENT_NO_CACHE);
-        mEmojiPager.setPersistentDrawingCache(PERSISTENT_NO_CACHE);
+        mEmojiLayoutParams.setEmojiListProperties(mEmojiRecyclerView);
-        mEmojiLayoutParams.setPagerProperties(mEmojiPager);
 
         mEmojiCategoryPageIndicatorView =
                 findViewById(R.id.emoji_category_page_id_view);
@@ -283,8 +279,10 @@ public final class EmojiPalettesView extends LinearLayout
         AudioAndHapticFeedbackManager.getInstance().performHapticAndAudioFeedback(
                 Constants.CODE_UNSPECIFIED, this);
         final int categoryId = mEmojiCategory.getCategoryId(tabId);
-        setCurrentCategoryAndPageId(categoryId, 0, false /* force */);
+        if (categoryId != mEmojiCategory.getCurrentCategoryId()) {
-        updateEmojiCategoryPageIdView();
+            setCurrentCategoryAndPageId(categoryId, 0, false /* force */);
+            updateEmojiCategoryPageIdView();
+        }
     }
 
     /**
@@ -388,14 +386,17 @@ public final class EmojiPalettesView extends LinearLayout
         final KeyDrawParams params = new KeyDrawParams();
         params.updateParams(mEmojiLayoutParams.getActionBarHeight(), keyVisualAttr);
         setupAlphabetKey(mAlphabetKeyLeft, switchToAlphaLabel, params);
-        mEmojiPager.setAdapter(mEmojiPalettesAdapter);
+        if (mEmojiRecyclerView.getAdapter() == null) {
-        mEmojiPager.setCurrentItem(mCurrentPagerPosition, false);
+            mEmojiRecyclerView.setAdapter(mEmojiPalettesAdapter);
+            setCurrentCategoryAndPageId(mEmojiCategory.getCurrentCategoryId(), mEmojiCategory.getCurrentCategoryPageId(),
+                    true /* force */);
+        }
     }
 
     public void stopEmojiPalettes() {
         mEmojiPalettesAdapter.releaseCurrentKey(true /* withKeyRegistering */);
         mEmojiPalettesAdapter.flushPendingRecentKeys();
-        mEmojiPager.setAdapter(null);
+        mEmojiRecyclerView.setAdapter(null);
     }
 
     public void setKeyboardActionListener(final KeyboardActionListener listener) {
@@ -408,19 +409,14 @@ public final class EmojiPalettesView extends LinearLayout
             return;
         }
         mEmojiCategoryPageIndicatorView.setCategoryPageId(
-                mEmojiCategory.getCurrentCategoryPageSize(),
+                mEmojiCategory.getCurrentCategoryPageCount(),
                 mEmojiCategory.getCurrentCategoryPageId(), 0.0f /* offset */);
     }
 
     private void setCurrentCategoryAndPageId(final int categoryId, final int categoryPageId,
                             final boolean force) {
         final int oldCategoryId = mEmojiCategory.getCurrentCategoryId();
-        final int oldPageId = mEmojiCategory.getCurrentCategoryPageId();
+        final int oldCategoryPageId = mEmojiCategory.getCurrentCategoryPageId();
-        final boolean firstPage = categoryPageId == 0;
-        mEmojiCategory.setCurrentCategoryPageId(categoryPageId);
-        if (oldCategoryId == categoryId && (!firstPage || oldPageId == 0) && !force) {
-            return;
-        }
 
         if (oldCategoryId == EmojiCategory.ID_RECENTS && categoryId != EmojiCategory.ID_RECENTS) {
             // Needs to save pending updates for recent keys when we get out of the recents
@@ -429,13 +425,11 @@ public final class EmojiPalettesView extends LinearLayout
             mEmojiPalettesAdapter.flushPendingRecentKeys();
         }
 
-        mEmojiCategory.setCurrentCategoryId(categoryId);
+        if (force || oldCategoryId != categoryId || oldCategoryPageId != categoryPageId) {
-        final Pair<Integer, Integer> pagerIds = mEmojiCategory.getCategoryIdAndPageIdFromPagePosition(
+            mEmojiCategory.setCurrentCategoryId(categoryId);
-                mEmojiPager.getCurrentItem());
+            mEmojiCategory.setCurrentCategoryPageId(categoryPageId);
-        if (force || pagerIds.first != categoryId || (firstPage && pagerIds.second != 0)) {
+            mEmojiPalettesAdapter.notifyDataSetChanged();
-            final int newPagerPageId = mEmojiCategory.getPagerPageIdFromCategoryAndPageId(categoryId, categoryPageId);
+            mEmojiRecyclerView.scrollToPosition(categoryPageId);
-            final boolean smooth = pagerIds.first == categoryId && firstPage && pagerIds.second != 0;
-            mEmojiPager.setCurrentItem(newPagerPageId, smooth /* smoothScroll */);
         }
 
         final int newTabId = mEmojiCategory.getTabIdFromCategoryId(categoryId);

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

@@ -59,8 +59,8 @@
             </FrameLayout>
         </org.dslul.openboard.inputmethod.compat.TabHostCompat>
     </LinearLayout>
-    <androidx.viewpager2.widget.ViewPager2
+    <androidx.recyclerview.widget.RecyclerView
-        android:id="@+id/emoji_keyboard_pager"
+        android:id="@+id/emoji_keyboard_list"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical" />

app/src/main/res/values-land/config.xml

@@ -77,8 +77,9 @@
     <dimen name="config_gesture_floating_preview_vertical_padding">15dp</dimen>
 
     <!-- Emoji keyboard -->
-    <fraction name="config_emoji_keyboard_key_width">10%p</fraction>
+    <fraction name="config_emoji_keyboard_key_width">8.33%p</fraction>
-    <fraction name="config_emoji_keyboard_row_height">50%p</fraction>
+    <fraction name="config_emoji_keyboard_row_height">40%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">54%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">70%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">20</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">70%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">32</integer>
 </resources>

app/src/main/res/values-sw600dp-land/config.xml

@@ -65,8 +65,9 @@
     <dimen name="config_gesture_floating_preview_vertical_padding">17dp</dimen>
 
     <!-- Emoji keyboard -->
-    <fraction name="config_emoji_keyboard_key_width">10%p</fraction>
+    <fraction name="config_emoji_keyboard_key_width">8.33%p</fraction>
-    <fraction name="config_emoji_keyboard_row_height">33%p</fraction>
+    <fraction name="config_emoji_keyboard_row_height">40%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">70%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">64%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">30</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">64%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">36</integer>
 </resources>

app/src/main/res/values-sw600dp/config.xml

@@ -82,8 +82,9 @@
     <dimen name="config_gesture_floating_preview_round_radius">3dp</dimen>
 
     <!-- Emoji keyboard -->
-    <fraction name="config_emoji_keyboard_key_width">12.5%p</fraction>
+    <fraction name="config_emoji_keyboard_key_width">11.11%p</fraction>
-    <fraction name="config_emoji_keyboard_row_height">33%p</fraction>
+    <fraction name="config_emoji_keyboard_row_height">28%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">60%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">78%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">24</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">78%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">36</integer>
 </resources>

app/src/main/res/values-sw768dp-land/config.xml

@@ -65,6 +65,7 @@
     <!-- Emoji keyboard -->
     <fraction name="config_emoji_keyboard_key_width">7.69%p</fraction>
     <fraction name="config_emoji_keyboard_row_height">33%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">60%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">58%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">39</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">58%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">39</integer>
 </resources>

app/src/main/res/values-sw768dp/config.xml

@@ -81,7 +81,8 @@
 
     <!-- Emoji keyboard -->
     <fraction name="config_emoji_keyboard_key_width">10%p</fraction>
-    <fraction name="config_emoji_keyboard_row_height">33%p</fraction>
+    <fraction name="config_emoji_keyboard_row_height">30%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">68%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">64%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">30</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">64%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">39</integer>
 </resources>

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

@@ -88,9 +88,10 @@
 
     <!-- Emoji keyboard -->
     <fraction name="config_emoji_keyboard_key_width">12.5%p</fraction>
-    <fraction name="config_emoji_keyboard_row_height">33%p</fraction>
+    <fraction name="config_emoji_keyboard_row_height">28%p</fraction>
-    <fraction name="config_emoji_keyboard_key_letter_size">68%p</fraction>
+    <fraction name="config_emoji_keyboard_key_letter_size">78%p</fraction>
-    <integer name="config_emoji_keyboard_max_page_key_count">24</integer>
+    <fraction name="config_emoji_keyboard_key_label_size">78%p</fraction>
+    <integer name="config_emoji_keyboard_max_recents_key_count">32</integer>
 
     <!-- Key codes of hardware keys that can be used to toggle the Emoji layout.
          Each array defines a comma-separated tuple containing:

app/src/main/res/xml/kbd_emoji_category1.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category10.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category2.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category3.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category4.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category5.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category6.xml

@@ -21,8 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
-    latin:keyLabelSize="60%p"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category7.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category8.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_category9.xml

@@ -21,7 +21,8 @@
 <Keyboard
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
-    latin:keyLetterSize="90%p"
+    latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows

app/src/main/res/xml/kbd_emoji_recents.xml

@@ -22,7 +22,7 @@
     xmlns:latin="http://schemas.android.com/apk/res-auto"
     latin:keyWidth="@fraction/config_emoji_keyboard_key_width"
     latin:keyLetterSize="@fraction/config_emoji_keyboard_key_letter_size"
-    latin:keyLabelSize="60%p"
+    latin:keyLabelSize="@fraction/config_emoji_keyboard_key_label_size"
     latin:rowHeight="@fraction/config_emoji_keyboard_row_height"
 >
     <GridRows