Cleanup key drawing code

This change also modifies 9-patch drawables to fix the following
issues.  In order to draw key background drawable just on the
coordinates we want, we have to know where an actual "visible" part is
in the drawable.  The only clue we can use is "padding" of the
drawable.  To achieve this, the 9-patch drawable must have its
"visible" part marked as "content".  Please refer the Bug: 4948171 for
more detailed explanation.

This change also reverts the following "black" drawables back from
Gingerbread because recent change broke these (I70019a91).
  * drawable-hdpi/sym_bkeyboard_*.png
  * drawable-hdpi/btn_keyboard_key_*_stone.9.png

Bug: 4948171
Change-Id: I6e4d03b3144caa95c793aac97af22df34c5f454f

1 files changed, 269 insertions, 198 deletions

diff --git a/java/src/com/android/inputmethod/keyboard/KeyboardView.java b/java/src/com/android/inputmethod/keyboard/KeyboardView.java
index 58360275d..203cde915 100644
--- a/java/src/com/android/inputmethod/keyboard/KeyboardView.java
+++ b/java/src/com/android/inputmethod/keyboard/KeyboardView.java
@@ -71,6 +71,9 @@ import java.util.WeakHashMap;
  * @attr ref R.styleable#KeyboardView_keyHintLetterRatio
  * @attr ref R.styleable#KeyboardView_keyUppercaseLetterRatio
  * @attr ref R.styleable#KeyboardView_keyHintLabelRatio
+ * @attr ref R.styleable#KeyboardView_keyLabelHorizontalPadding
+ * @attr ref R.styleable#KeyboardView_keyHintLetterPadding
+ * @attr ref R.styleable#KeyboardView_keyUppercaseLetterPadding
  * @attr ref R.styleable#KeyboardView_keyTextStyle
  * @attr ref R.styleable#KeyboardView_keyPreviewLayout
  * @attr ref R.styleable#KeyboardView_keyPreviewTextRatio
@@ -89,7 +92,6 @@ import java.util.WeakHashMap;
  */
 public class KeyboardView extends View implements PointerTracker.UIProxy {
     private static final String TAG = KeyboardView.class.getSimpleName();
-    private static final boolean DEBUG_SHOW_ALIGN = LatinImeLogger.sVISUALDEBUG;
     private static final boolean DEBUG_KEYBOARD_GRID = false;
 
     private static final boolean ENABLE_CAPSLOCK_BY_LONGPRESS = true;
@@ -102,55 +104,25 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
     private static final int[] LONG_PRESSABLE_STATE_SET = { android.R.attr.state_long_pressable };
 
     // XML attribute
-    private final int mKeyTextColor;
-    private final int mKeyTextInactivatedColor;
-    private final Typeface mKeyTextStyle;
-    private final float mKeyLetterRatio;
-    private final float mKeyLargeLetterRatio;
-    private final float mKeyLabelRatio;
-    private final float mKeyHintLetterRatio;
-    private final float mKeyUppercaseLetterRatio;
-    private final float mKeyHintLabelRatio;
-    private final int mShadowColor;
-    private final float mShadowRadius;
-    private final Drawable mKeyBackground;
     private final float mBackgroundDimAmount;
     private final float mKeyHysteresisDistance;
     private final float mVerticalCorrection;
-    private final Drawable mPreviewBackground;
-    private final Drawable mPreviewLeftBackground;
-    private final Drawable mPreviewRightBackground;
-    private final Drawable mPreviewSpacebarBackground;
-    private final int mPreviewTextColor;
-    private final float mPreviewTextRatio;
-    private final int mPreviewOffset;
-    private final int mPreviewHeight;
     private final int mPopupLayout;
-    private final int mKeyHintLetterColor;
-    private final int mKeyHintLabelColor;
-    private final int mKeyUppercaseLetterInactivatedColor;
-    private final int mKeyUppercaseLetterActivatedColor;
 
     // HORIZONTAL ELLIPSIS "...", character for popup hint.
     private static final String POPUP_HINT_CHAR = "\u2026";
 
     // Main keyboard
     private Keyboard mKeyboard;
-    private int mKeyLetterSize;
-    private int mKeyLargeLetterSize;
-    private int mKeyLabelSize;
-    private int mKeyHintLetterSize;
-    private int mKeyUppercaseLetterSize;
-    private int mKeyHintLabelSize;
+    private final KeyDrawParams mKeyDrawParams;
 
     // Key preview
+    private final KeyPreviewDrawParams mKeyPreviewDrawParams;
     private final TextView mPreviewText;
-    private int mPreviewTextSize;
     private boolean mShowKeyPreviewPopup = true;
     private final int mDelayBeforePreview;
     private int mDelayAfterPreview;
     private ViewGroup mPreviewPlacer;
-    private final int[] mCoordinates = new int[2];
 
     // Mini keyboard
     private PopupWindow mPopupWindow;
@@ -194,16 +166,13 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
     /** The canvas for the above mutable keyboard bitmap */
     private Canvas mCanvas;
     private final Paint mPaint = new Paint();
-    private final Rect mPadding = new Rect();
     // This map caches key label text height in pixel as value and key label text size as map key.
-    private final HashMap<Integer, Integer> mTextHeightCache = new HashMap<Integer, Integer>();
+    private static final HashMap<Integer, Float> sTextHeightCache =
+            new HashMap<Integer, Float>();
     // This map caches key label text width in pixel as value and key label text size as map key.
-    private final HashMap<Integer, Integer> mTextWidthCache = new HashMap<Integer, Integer>();
-    // Distance from horizontal center of the key, proportional to key label text height and width.
-    private static final float KEY_LABEL_VERTICAL_ADJUSTMENT_FACTOR_CENTER = 0.45f;
-    private static final float KEY_LABEL_VERTICAL_PADDING_FACTOR = 1.60f;
+    private static final HashMap<Integer, Float> sTextWidthCache =
+            new HashMap<Integer, Float>();
     private static final String KEY_LABEL_REFERENCE_CHAR = "M";
-    private final int mKeyLabelHorizontalPadding;
 
     private static final int MEASURESPEC_UNSPECIFIED = MeasureSpec.makeMeasureSpec(
             0, MeasureSpec.UNSPECIFIED);
@@ -334,6 +303,122 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         }
     }
 
+    private static class KeyDrawParams {
+        // XML attributes
+        public final int mKeyTextColor;
+        public final int mKeyTextInactivatedColor;
+        public final Typeface mKeyTextStyle;
+        public final float mKeyLabelHorizontalPadding;
+        public final float mKeyHintLetterPadding;
+        public final float mKeyUppercaseLetterPadding;
+        public final int mShadowColor;
+        public final float mShadowRadius;
+        public final Drawable mKeyBackground;
+        public final int mKeyHintLetterColor;
+        public final int mKeyHintLabelColor;
+        public final int mKeyUppercaseLetterInactivatedColor;
+        public final int mKeyUppercaseLetterActivatedColor;
+
+        private final float mKeyLetterRatio;
+        private final float mKeyLargeLetterRatio;
+        private final float mKeyLabelRatio;
+        private final float mKeyHintLetterRatio;
+        private final float mKeyUppercaseLetterRatio;
+        private final float mKeyHintLabelRatio;
+
+        public final Rect mPadding = new Rect();
+        public int mKeyLetterSize;
+        public int mKeyLargeLetterSize;
+        public int mKeyLabelSize;
+        public int mKeyHintLetterSize;
+        public int mKeyUppercaseLetterSize;
+        public int mKeyHintLabelSize;
+
+        public KeyDrawParams(TypedArray a) {
+            mKeyBackground = a.getDrawable(R.styleable.KeyboardView_keyBackground);
+            mKeyLetterRatio = getRatio(a, R.styleable.KeyboardView_keyLetterRatio);
+            mKeyLargeLetterRatio = getRatio(a, R.styleable.KeyboardView_keyLargeLetterRatio);
+            mKeyLabelRatio = getRatio(a, R.styleable.KeyboardView_keyLabelRatio);
+            mKeyHintLetterRatio = getRatio(a, R.styleable.KeyboardView_keyHintLetterRatio);
+            mKeyUppercaseLetterRatio = getRatio(a,
+                    R.styleable.KeyboardView_keyUppercaseLetterRatio);
+            mKeyHintLabelRatio = getRatio(a, R.styleable.KeyboardView_keyHintLabelRatio);
+            mKeyLabelHorizontalPadding = a.getDimension(
+                    R.styleable.KeyboardView_keyLabelHorizontalPadding, 0);
+            mKeyHintLetterPadding = a.getDimension(
+                    R.styleable.KeyboardView_keyHintLetterPadding, 0);
+            mKeyUppercaseLetterPadding = a.getDimension(
+                    R.styleable.KeyboardView_keyUppercaseLetterPadding, 0);
+            mKeyTextColor = a.getColor(R.styleable.KeyboardView_keyTextColor, 0xFF000000);
+            mKeyTextInactivatedColor = a.getColor(
+                    R.styleable.KeyboardView_keyTextInactivatedColor, 0xFF000000);
+            mKeyHintLetterColor = a.getColor(R.styleable.KeyboardView_keyHintLetterColor, 0);
+            mKeyHintLabelColor = a.getColor(R.styleable.KeyboardView_keyHintLabelColor, 0);
+            mKeyUppercaseLetterInactivatedColor = a.getColor(
+                    R.styleable.KeyboardView_keyUppercaseLetterInactivatedColor, 0);
+            mKeyUppercaseLetterActivatedColor = a.getColor(
+                    R.styleable.KeyboardView_keyUppercaseLetterActivatedColor, 0);
+            mKeyTextStyle = Typeface.defaultFromStyle(
+                    a.getInt(R.styleable.KeyboardView_keyTextStyle, Typeface.NORMAL));
+            mShadowColor = a.getColor(R.styleable.KeyboardView_shadowColor, 0);
+            mShadowRadius = a.getFloat(R.styleable.KeyboardView_shadowRadius, 0f);
+
+            mKeyBackground.getPadding(mPadding);
+        }
+
+        public void updateKeyHeight(int keyHeight) {
+            mKeyLetterSize = (int)(keyHeight * mKeyLetterRatio);
+            mKeyLargeLetterSize = (int)(keyHeight * mKeyLargeLetterRatio);
+            mKeyLabelSize = (int)(keyHeight * mKeyLabelRatio);
+            mKeyHintLetterSize = (int)(keyHeight * mKeyHintLetterRatio);
+            mKeyUppercaseLetterSize = (int)(keyHeight * mKeyUppercaseLetterRatio);
+            mKeyHintLabelSize = (int)(keyHeight * mKeyHintLabelRatio);
+        }
+    }
+
+    private static class KeyPreviewDrawParams {
+        // XML attributes.
+        public final Drawable mPreviewBackground;
+        public final Drawable mPreviewLeftBackground;
+        public final Drawable mPreviewRightBackground;
+        public final Drawable mPreviewSpacebarBackground;
+        public final int mPreviewTextColor;
+        public final int mPreviewOffset;
+        public final int mPreviewHeight;
+        public final Typeface mKeyTextStyle;
+
+        private final float mPreviewTextRatio;
+        private final float mKeyLetterRatio;
+
+        public int mPreviewTextSize;
+        public int mKeyLetterSize;
+        public final int[] mCoordinates = new int[2];
+
+        public KeyPreviewDrawParams(TypedArray a, KeyDrawParams keyDrawParams) {
+            mPreviewBackground = a.getDrawable(R.styleable.KeyboardView_keyPreviewBackground);
+            mPreviewLeftBackground = a.getDrawable(
+                    R.styleable.KeyboardView_keyPreviewLeftBackground);
+            mPreviewRightBackground = a.getDrawable(
+                    R.styleable.KeyboardView_keyPreviewRightBackground);
+            mPreviewSpacebarBackground = a.getDrawable(
+                    R.styleable.KeyboardView_keyPreviewSpacebarBackground);
+            mPreviewOffset = a.getDimensionPixelOffset(
+                    R.styleable.KeyboardView_keyPreviewOffset, 0);
+            mPreviewHeight = a.getDimensionPixelSize(
+                    R.styleable.KeyboardView_keyPreviewHeight, 80);
+            mPreviewTextRatio = getRatio(a, R.styleable.KeyboardView_keyPreviewTextRatio);
+            mPreviewTextColor = a.getColor(R.styleable.KeyboardView_keyPreviewTextColor, 0);
+
+            mKeyLetterRatio = keyDrawParams.mKeyLetterRatio;
+            mKeyTextStyle = keyDrawParams.mKeyTextStyle;
+        }
+
+        public void updateKeyHeight(int keyHeight) {
+            mPreviewTextSize = (int)(keyHeight * mPreviewTextRatio);
+            mKeyLetterSize = (int)(keyHeight * mKeyLetterRatio);
+        }
+    }
+
     public KeyboardView(Context context, AttributeSet attrs) {
         this(context, attrs, R.attr.keyboardViewStyle);
     }
@@ -344,49 +429,20 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         final TypedArray a = context.obtainStyledAttributes(
                 attrs, R.styleable.KeyboardView, defStyle, R.style.KeyboardView);
 
-        mKeyBackground = a.getDrawable(R.styleable.KeyboardView_keyBackground);
+        mKeyDrawParams = new KeyDrawParams(a);
+        mKeyPreviewDrawParams = new KeyPreviewDrawParams(a, mKeyDrawParams);
         mKeyHysteresisDistance = a.getDimensionPixelOffset(
                 R.styleable.KeyboardView_keyHysteresisDistance, 0);
         mVerticalCorrection = a.getDimensionPixelOffset(
                 R.styleable.KeyboardView_verticalCorrection, 0);
-        mPreviewTextColor = a.getColor(R.styleable.KeyboardView_keyPreviewTextColor, 0);
         final int previewLayout = a.getResourceId(R.styleable.KeyboardView_keyPreviewLayout, 0);
         if (previewLayout != 0) {
             mPreviewText = (TextView) LayoutInflater.from(context).inflate(previewLayout, null);
-            mPreviewText.setTextColor(mPreviewTextColor);
         } else {
             mPreviewText = null;
             mShowKeyPreviewPopup = false;
         }
-        mPreviewBackground = a.getDrawable(R.styleable.KeyboardView_keyPreviewBackground);
-        mPreviewLeftBackground = a.getDrawable(R.styleable.KeyboardView_keyPreviewLeftBackground);
-        mPreviewRightBackground = a.getDrawable(R.styleable.KeyboardView_keyPreviewRightBackground);
-        mPreviewSpacebarBackground = a.getDrawable(
-                R.styleable.KeyboardView_keyPreviewSpacebarBackground);
-        mPreviewOffset = a.getDimensionPixelOffset(R.styleable.KeyboardView_keyPreviewOffset, 0);
-        mPreviewHeight = a.getDimensionPixelSize(R.styleable.KeyboardView_keyPreviewHeight, 80);
-        mKeyLetterRatio = getRatio(a, R.styleable.KeyboardView_keyLetterRatio);
-        mKeyLargeLetterRatio = getRatio(a, R.styleable.KeyboardView_keyLargeLetterRatio);
-        mKeyLabelRatio = getRatio(a, R.styleable.KeyboardView_keyLabelRatio);
-        mKeyHintLetterRatio = getRatio(a, R.styleable.KeyboardView_keyHintLetterRatio);
-        mKeyUppercaseLetterRatio = getRatio(a,
-                R.styleable.KeyboardView_keyUppercaseLetterRatio);
-        mKeyHintLabelRatio = getRatio(a, R.styleable.KeyboardView_keyHintLabelRatio);
-        mPreviewTextRatio = getRatio(a, R.styleable.KeyboardView_keyPreviewTextRatio);
-        mKeyTextColor = a.getColor(R.styleable.KeyboardView_keyTextColor, 0xFF000000);
-        mKeyTextInactivatedColor = a.getColor(
-                R.styleable.KeyboardView_keyTextInactivatedColor, 0xFF000000);
-        mKeyHintLetterColor = a.getColor(R.styleable.KeyboardView_keyHintLetterColor, 0);
-        mKeyHintLabelColor = a.getColor(R.styleable.KeyboardView_keyHintLabelColor, 0);
-        mKeyUppercaseLetterInactivatedColor = a.getColor(
-                R.styleable.KeyboardView_keyUppercaseLetterInactivatedColor, 0);
-        mKeyUppercaseLetterActivatedColor = a.getColor(
-                R.styleable.KeyboardView_keyUppercaseLetterActivatedColor, 0);
-        mKeyTextStyle = Typeface.defaultFromStyle(
-                a.getInt(R.styleable.KeyboardView_keyTextStyle, Typeface.NORMAL));
         mPopupLayout = a.getResourceId(R.styleable.KeyboardView_popupLayout, 0);
-        mShadowColor = a.getColor(R.styleable.KeyboardView_shadowColor, 0);
-        mShadowRadius = a.getFloat(R.styleable.KeyboardView_shadowRadius, 0f);
         // TODO: Use Theme (android.R.styleable.Theme_backgroundDimAmount)
         mBackgroundDimAmount = a.getFloat(R.styleable.KeyboardView_backgroundDimAmount, 0.5f);
         a.recycle();
@@ -395,15 +451,11 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
 
         mDelayBeforePreview = res.getInteger(R.integer.config_delay_before_preview);
         mDelayAfterPreview = res.getInteger(R.integer.config_delay_after_preview);
-        mKeyLabelHorizontalPadding = (int)res.getDimension(
-                R.dimen.key_label_horizontal_alignment_padding);
 
         mPaint.setAntiAlias(true);
         mPaint.setTextAlign(Align.CENTER);
         mPaint.setAlpha(255);
 
-        mKeyBackground.getPadding(mPadding);
-
         mSwipeThreshold = (int) (500 * res.getDisplayMetrics().density);
         // TODO: Refer to frameworks/base/core/res/res/values/config.xml
         mDisambiguateSwipe = res.getBoolean(R.bool.config_swipeDisambiguation);
@@ -539,14 +591,8 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         mKeyDetector.setProximityThreshold(keyboard.getMostCommonKeyWidth());
         mPopupPanelCache.clear();
         final int keyHeight = keyboard.getRowHeight() - keyboard.getVerticalGap();
-        mKeyLetterSize = (int)(keyHeight * mKeyLetterRatio);
-        mKeyLargeLetterSize = (int)(keyHeight * mKeyLargeLetterRatio);
-        mKeyLabelSize = (int)(keyHeight * mKeyLabelRatio);
-        mKeyHintLetterSize = (int)(keyHeight * mKeyHintLetterRatio);
-        mKeyUppercaseLetterSize = (int)(
-                keyHeight * mKeyUppercaseLetterRatio);
-        mKeyHintLabelSize = (int)(keyHeight * mKeyHintLabelRatio);
-        mPreviewTextSize = (int)(keyHeight * mPreviewTextRatio);
+        mKeyDrawParams.updateKeyHeight(keyHeight);
+        mKeyPreviewDrawParams.updateKeyHeight(keyHeight);
     }
 
     /**
@@ -605,14 +651,6 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         return mKeyDetector.isProximityCorrectionEnabled();
     }
 
-    protected CharSequence adjustCase(CharSequence label) {
-        if (mKeyboard.isShiftedOrShiftLocked() && label != null && label.length() < 3
-                && Character.isLowerCase(label.charAt(0))) {
-            return label.toString().toUpperCase(mKeyboard.mId.mLocale);
-        }
-        return label;
-    }
-
     @Override
     public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         // Round up a little
@@ -663,13 +701,24 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
 
         if (mKeyboard == null) return;
 
+        final boolean isManualTemporaryUpperCase = mKeyboard.isManualTemporaryUpperCase();
+        final KeyDrawParams params = mKeyDrawParams;
         if (mInvalidatedKey != null && mInvalidatedKeyRect.contains(mDirtyRect)) {
             // Draw a single key.
-            onBufferDrawKey(canvas, mInvalidatedKey);
+            final int keyDrawX = mInvalidatedKey.mX + mInvalidatedKey.mVisualInsetsLeft
+                    + getPaddingLeft();
+            final int keyDrawY = mInvalidatedKey.mY + getPaddingTop();
+            canvas.translate(keyDrawX, keyDrawY);
+            onBufferDrawKey(mInvalidatedKey, canvas, mPaint, params, isManualTemporaryUpperCase);
+            canvas.translate(-keyDrawX, -keyDrawY);
         } else {
             // Draw all keys.
             for (final Key key : mKeyboard.getKeys()) {
-                onBufferDrawKey(canvas, key);
+                final int keyDrawX = key.mX + key.mVisualInsetsLeft + getPaddingLeft();
+                final int keyDrawY = key.mY + getPaddingTop();
+                canvas.translate(keyDrawX, keyDrawY);
+                onBufferDrawKey(key, canvas, mPaint, params, isManualTemporaryUpperCase);
+                canvas.translate(-keyDrawX, -keyDrawY);
             }
         }
 
@@ -702,58 +751,61 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         mDirtyRect.setEmpty();
     }
 
-    private void onBufferDrawKey(final Canvas canvas, final Key key) {
-        final Paint paint = mPaint;
-        final Drawable keyBackground = mKeyBackground;
-        final Rect padding = mPadding;
-        final int kbdPaddingLeft = getPaddingLeft();
-        final int kbdPaddingTop = getPaddingTop();
-        final int keyDrawX = key.mX + key.mVisualInsetsLeft;
-        final int keyDrawWidth = key.mWidth - key.mVisualInsetsLeft - key.mVisualInsetsRight;
-        final int centerX = (keyDrawWidth + padding.left - padding.right) / 2;
-        final float centerY = (key.mHeight + padding.top - padding.bottom) / 2;
-        final int rowHeight = padding.top + key.mHeight;
-        final boolean isManualTemporaryUpperCase = mKeyboard.isManualTemporaryUpperCase();
-
-        canvas.translate(keyDrawX + kbdPaddingLeft, key.mY + kbdPaddingTop);
-
+    private static void onBufferDrawKey(final Key key, final Canvas canvas, Paint paint,
+            KeyDrawParams params, boolean isManualTemporaryUpperCase) {
+        final boolean debugShowAlign = LatinImeLogger.sVISUALDEBUG;
         // Draw key background.
+        final int bgWidth = key.mWidth - key.mVisualInsetsLeft - key.mVisualInsetsRight
+                + params.mPadding.left + params.mPadding.right;
+        final int bgHeight = key.mHeight + params.mPadding.top + params.mPadding.bottom;
+        final int bgX = -params.mPadding.left;
+        final int bgY = -params.mPadding.top;
         final int[] drawableState = key.getCurrentDrawableState();
-        keyBackground.setState(drawableState);
-        final Rect bounds = keyBackground.getBounds();
-        if (keyDrawWidth != bounds.right || key.mHeight != bounds.bottom) {
-            keyBackground.setBounds(0, 0, keyDrawWidth, key.mHeight);
+        final Drawable background = params.mKeyBackground;
+        background.setState(drawableState);
+        final Rect bounds = background.getBounds();
+        if (bgWidth != bounds.right || bgHeight != bounds.bottom) {
+            background.setBounds(0, 0, bgWidth, bgHeight);
+        }
+        canvas.translate(bgX, bgY);
+        background.draw(canvas);
+        if (debugShowAlign) {
+            drawRectangle(canvas, 0, 0, bgWidth, bgHeight, 0x80c00000, new Paint());
+        }
+        canvas.translate(-bgX, -bgY);
+
+        // Draw key top visuals.
+        final int keyWidth = key.mWidth;
+        final int keyHeight = key.mHeight;
+        final float centerX = keyWidth * 0.5f;
+        final float centerY = keyHeight * 0.5f;
+
+        if (debugShowAlign) {
+            drawRectangle(canvas, 0, 0, keyWidth, keyHeight, 0x800000c0, new Paint());
         }
-        keyBackground.draw(canvas);
 
         // Draw key label.
-        int positionX = centerX;
+        float positionX = centerX;
         if (key.mLabel != null) {
             // Switch the character to uppercase if shift is pressed
-            final CharSequence label = key.mLabel == null ? null : adjustCase(key.mLabel);
+            final CharSequence label = key.getCaseAdjustedLabel();
             // For characters, use large font. For labels like "Done", use smaller font.
-            paint.setTypeface(key.selectTypeface(mKeyTextStyle));
-            final int labelSize = key.selectTextSize(mKeyLetterSize, mKeyLargeLetterSize,
-                    mKeyLabelSize, mKeyHintLabelSize);
+            paint.setTypeface(key.selectTypeface(params.mKeyTextStyle));
+            final int labelSize = key.selectTextSize(params.mKeyLetterSize,
+                    params.mKeyLargeLetterSize, params.mKeyLabelSize, params.mKeyHintLabelSize);
             paint.setTextSize(labelSize);
-            final int labelCharHeight = getLabelCharHeight(paint);
-            final int labelCharWidth = getLabelCharWidth(paint);
+            final float labelCharHeight = getCharHeight(paint);
+            final float labelCharWidth = getCharWidth(paint);
 
             // Vertical label text alignment.
-            final float baseline;
-            // TODO: Generalize the following calculations.
-            if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_BOTTOM) != 0) {
-                baseline = key.mHeight - labelCharHeight * KEY_LABEL_VERTICAL_PADDING_FACTOR;
-            } else { // Align center
-                baseline = centerY + labelCharHeight * KEY_LABEL_VERTICAL_ADJUSTMENT_FACTOR_CENTER;
-            }
+            final float baseline = centerY + labelCharHeight / 2;
 
             // Horizontal label text alignment
             if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_LEFT) != 0) {
-                positionX = padding.left + mKeyLabelHorizontalPadding;
+                positionX = (int)params.mKeyLabelHorizontalPadding;
                 paint.setTextAlign(Align.LEFT);
             } else if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_RIGHT) != 0) {
-                positionX = keyDrawWidth - mKeyLabelHorizontalPadding - padding.right;
+                positionX = keyWidth - (int)params.mKeyLabelHorizontalPadding;
                 paint.setTextAlign(Align.RIGHT);
             } else if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_LEFT_OF_CENTER) != 0) {
                 // TODO: Parameterise this?
@@ -763,20 +815,15 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
                 positionX = centerX;
                 paint.setTextAlign(Align.CENTER);
             }
-            if (DEBUG_SHOW_ALIGN) {
-                final Paint line = new Paint();
-                drawHorizontalLine(canvas, (int)baseline, keyDrawWidth, 0xc0008000, line);
-                drawVerticalLine(canvas, positionX, rowHeight, 0xc0800080, line);
-            }
 
             if (key.hasUppercaseLetter() && isManualTemporaryUpperCase) {
-                paint.setColor(mKeyTextInactivatedColor);
+                paint.setColor(params.mKeyTextInactivatedColor);
             } else {
-                paint.setColor(mKeyTextColor);
+                paint.setColor(params.mKeyTextColor);
             }
             if (key.isEnabled()) {
                 // Set a drop shadow for the text
-                paint.setShadowLayer(mShadowRadius, 0, 0, mShadowColor);
+                paint.setShadowLayer(params.mShadowRadius, 0, 0, params.mShadowColor);
             } else {
                 // Make label invisible
                 paint.setColor(Color.TRANSPARENT);
@@ -785,6 +832,11 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             // Turn off drop shadow
             paint.setShadowLayer(0, 0, 0, 0);
 
+            if (debugShowAlign) {
+                final Paint line = new Paint();
+                drawHorizontalLine(canvas, baseline, keyWidth, 0xc0008000, line);
+                drawVerticalLine(canvas, positionX, keyHeight, 0xc0800080, line);
+            }
         }
 
         // Draw hint label.
@@ -792,31 +844,44 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             final CharSequence hint = key.mHintLabel;
             final int hintColor;
             final int hintSize;
-            if (key.hasUppercaseLetter()) {
-                hintColor = isManualTemporaryUpperCase ? mKeyUppercaseLetterActivatedColor
-                        : mKeyUppercaseLetterInactivatedColor;
-                hintSize = mKeyUppercaseLetterSize;
-            } else if (key.hasHintLabel()) {
-                hintColor = mKeyHintLabelColor;
-                hintSize = mKeyHintLabelSize;
+            if (key.hasHintLabel()) {
+                hintColor = params.mKeyHintLabelColor;
+                hintSize = params.mKeyHintLabelSize;
                 paint.setTypeface(Typeface.DEFAULT);
-            } else {
-                hintColor = mKeyHintLetterColor;
-                hintSize = mKeyHintLetterSize;
+            } else if (key.hasUppercaseLetter()) {
+                hintColor = isManualTemporaryUpperCase
+                        ? params.mKeyUppercaseLetterActivatedColor
+                        : params.mKeyUppercaseLetterInactivatedColor;
+                hintSize = params.mKeyUppercaseLetterSize;
+            } else { // key.hasHintLetter()
+                hintColor = params.mKeyHintLetterColor;
+                hintSize = params.mKeyHintLetterSize;
             }
             paint.setColor(hintColor);
             paint.setTextSize(hintSize);
-            // Note: padding.right for drawX?
+            final float hintCharWidth = getCharWidth(paint);
             final float hintX, hintY;
             if (key.hasHintLabel()) {
                 // TODO: Generalize the following calculations.
-                hintX = positionX + getLabelCharWidth(paint) * 2;
-                hintY = centerY + getLabelCharHeight(paint) / 2;
-            } else {
-                hintX = keyDrawWidth - getLabelCharWidth(paint);
-                hintY = -paint.ascent() + padding.top;
+                hintX = positionX + hintCharWidth * 2;
+                hintY = centerY + getCharHeight(paint) / 2;
+                paint.setTextAlign(Align.LEFT);
+            } else if (key.hasUppercaseLetter()) {
+                hintX = keyWidth - params.mKeyUppercaseLetterPadding - hintCharWidth / 2;
+                hintY = -paint.ascent() + params.mKeyUppercaseLetterPadding;
+                paint.setTextAlign(Align.CENTER);
+            } else { // key.hasHintLetter()
+                hintX = keyWidth - params.mKeyHintLetterPadding - hintCharWidth / 2;
+                hintY = -paint.ascent() + params.mKeyHintLetterPadding;
+                paint.setTextAlign(Align.CENTER);
             }
             canvas.drawText(hint, 0, hint.length(), hintX, hintY, paint);
+
+            if (debugShowAlign) {
+                final Paint line = new Paint();
+                drawHorizontalLine(canvas, (int)hintY, keyWidth, 0xc0808000, line);
+                drawVerticalLine(canvas, (int)hintX, keyHeight, 0xc0808000, line);
+            }
         }
 
         // Draw key icon.
@@ -825,63 +890,67 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             final int iconWidth = icon.getIntrinsicWidth();
             final int iconHeight = icon.getIntrinsicHeight();
             final int iconX, alignX;
-            final int iconY = (key.mHeight + padding.top - padding.bottom - iconHeight) / 2;
+            final int iconY = (keyHeight - iconHeight) / 2;
             if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_LEFT) != 0) {
-                iconX = padding.left + mKeyLabelHorizontalPadding;
+                iconX = (int)params.mKeyLabelHorizontalPadding;
                 alignX = iconX;
             } else if ((key.mLabelOption & Key.LABEL_OPTION_ALIGN_RIGHT) != 0) {
-                iconX = keyDrawWidth - padding.right - mKeyLabelHorizontalPadding - iconWidth;
+                iconX = keyWidth - (int)params.mKeyLabelHorizontalPadding - iconWidth;
                 alignX = iconX + iconWidth;
             } else { // Align center
-                iconX = (keyDrawWidth + padding.left - padding.right - iconWidth) / 2;
+                iconX = (keyWidth - iconWidth) / 2;
                 alignX = iconX + iconWidth / 2;
             }
             drawIcon(canvas, icon, iconX, iconY, iconWidth, iconHeight);
-            if (DEBUG_SHOW_ALIGN) {
+
+            if (debugShowAlign) {
                 final Paint line = new Paint();
-                drawVerticalLine(canvas, alignX, rowHeight, 0xc0800080, line);
+                drawVerticalLine(canvas, alignX, keyHeight, 0xc0800080, line);
                 drawRectangle(canvas, iconX, iconY, iconWidth, iconHeight, 0x80c00000, line);
             }
         }
 
         // Draw popup hint "..." at the bottom right corner of the key.
         if (key.hasPopupHint()) {
-            paint.setTextSize(mKeyHintLetterSize);
-            paint.setColor(mKeyHintLabelColor);
-            final int hintX = keyDrawWidth - getLabelCharWidth(paint);
-            // Using y-coordinate "key.mHeight - paint.descent()" draws "..." just on the bottom
-            // edge of the key. So we use slightly higher position by multiply descent length by 2.
-            final int hintY = key.mHeight - (int)paint.descent() * 2;
+            paint.setTextSize(params.mKeyHintLetterSize);
+            paint.setColor(params.mKeyHintLabelColor);
+            paint.setTextAlign(Align.CENTER);
+            final float hintX = keyWidth - params.mKeyHintLetterPadding - getCharWidth(paint) / 2;
+            final float hintY = keyHeight - params.mKeyHintLetterPadding;
             canvas.drawText(POPUP_HINT_CHAR, hintX, hintY, paint);
-        }
 
-        canvas.translate(-keyDrawX - kbdPaddingLeft, -key.mY - kbdPaddingTop);
+            if (debugShowAlign) {
+                final Paint line = new Paint();
+                drawHorizontalLine(canvas, (int)hintY, keyWidth, 0xc0808000, line);
+                drawVerticalLine(canvas, (int)hintX, keyHeight, 0xc0808000, line);
+            }
+        }
     }
 
     // This method is currently being used only by MiniKeyboardBuilder
     public int getDefaultLabelSizeAndSetPaint(Paint paint) {
         // For characters, use large font. For labels like "Done", use small font.
-        final int labelSize = mKeyLabelSize;
+        final int labelSize = mKeyDrawParams.mKeyLabelSize;
         paint.setTextSize(labelSize);
-        paint.setTypeface(mKeyTextStyle);
+        paint.setTypeface(mKeyDrawParams.mKeyTextStyle);
         return labelSize;
     }
 
-    private final Rect mTextBounds = new Rect();
+    private static final Rect sTextBounds = new Rect();
 
-    private int getLabelCharHeight(Paint paint) {
+    private static float getCharHeight(Paint paint) {
         final int labelSize = (int)paint.getTextSize();
-        final Integer cachedValue = mTextHeightCache.get(labelSize);
+        final Float cachedValue = sTextHeightCache.get(labelSize);
         if (cachedValue != null)
             return cachedValue;
 
-        paint.getTextBounds(KEY_LABEL_REFERENCE_CHAR, 0, 1, mTextBounds);
-        final int height = mTextBounds.height();
-        mTextHeightCache.put(labelSize, height);
+        paint.getTextBounds(KEY_LABEL_REFERENCE_CHAR, 0, 1, sTextBounds);
+        final float height = sTextBounds.height();
+        sTextHeightCache.put(labelSize, height);
         return height;
     }
 
-    private int getLabelCharWidth(Paint paint) {
+    private static float getCharWidth(Paint paint) {
         final int labelSize = (int)paint.getTextSize();
         final Typeface face = paint.getTypeface();
         final Integer key;
@@ -895,13 +964,13 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             key = labelSize;
         }
 
-        final Integer cached = mTextWidthCache.get(key);
+        final Float cached = sTextWidthCache.get(key);
         if (cached != null)
             return cached;
 
-        paint.getTextBounds(KEY_LABEL_REFERENCE_CHAR, 0, 1, mTextBounds);
-        final int width = mTextBounds.width();
-        mTextWidthCache.put(key, width);
+        paint.getTextBounds(KEY_LABEL_REFERENCE_CHAR, 0, 1, sTextBounds);
+        final float width = sTextBounds.width();
+        sTextWidthCache.put(key, width);
         return width;
     }
 
@@ -913,21 +982,21 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
         canvas.translate(-x, -y);
     }
 
-    private static void drawHorizontalLine(Canvas canvas, int y, int w, int color, Paint paint) {
+    private static void drawHorizontalLine(Canvas canvas, float y, float w, int color, Paint paint) {
         paint.setStyle(Paint.Style.STROKE);
         paint.setStrokeWidth(1.0f);
         paint.setColor(color);
         canvas.drawLine(0, y, w, y, paint);
     }
 
-    private static void drawVerticalLine(Canvas canvas, int x, int h, int color, Paint paint) {
+    private static void drawVerticalLine(Canvas canvas, float x, float h, int color, Paint paint) {
         paint.setStyle(Paint.Style.STROKE);
         paint.setStrokeWidth(1.0f);
         paint.setColor(color);
         canvas.drawLine(x, 0, x, h, paint);
     }
 
-    private static void drawRectangle(Canvas canvas, int x, int y, int w, int h, int color,
+    private static void drawRectangle(Canvas canvas, float x, float y, float w, float h, int color,
             Paint paint) {
         paint.setStyle(Paint.Style.STROKE);
         paint.setStrokeWidth(1.0f);
@@ -997,7 +1066,7 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             return;
 
         mHandler.cancelAllDismissKeyPreviews();
-
+        final KeyPreviewDrawParams params = mKeyPreviewDrawParams;
         final int keyDrawX = key.mX + key.mVisualInsetsLeft;
         final int keyDrawWidth = key.mWidth - key.mVisualInsetsLeft - key.mVisualInsetsRight;
         // What we show as preview should match what we show on key top in onBufferDraw(). 
@@ -1005,13 +1074,13 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             // TODO Should take care of temporaryShiftLabel here.
             previewText.setCompoundDrawables(null, null, null, null);
             if (key.mLabel.length() > 1) {
-                previewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, mKeyLetterSize);
+                previewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, params.mKeyLetterSize);
                 previewText.setTypeface(Typeface.DEFAULT_BOLD);
             } else {
-                previewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, mPreviewTextSize);
-                previewText.setTypeface(mKeyTextStyle);
+                previewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, params.mPreviewTextSize);
+                previewText.setTypeface(params.mKeyTextStyle);
             }
-            previewText.setText(adjustCase(tracker.getPreviewText(key)));
+            previewText.setText(key.getCaseAdjustedLabel());
         } else {
             final Drawable previewIcon = key.getPreviewIcon();
             previewText.setCompoundDrawables(null, null, null,
@@ -1019,29 +1088,31 @@ public class KeyboardView extends View implements PointerTracker.UIProxy {
             previewText.setText(null);
         }
         if (key.mCode == Keyboard.CODE_SPACE) {
-            previewText.setBackgroundDrawable(mPreviewSpacebarBackground);
+            previewText.setBackgroundDrawable(params.mPreviewSpacebarBackground);
         } else {
-            previewText.setBackgroundDrawable(mPreviewBackground);
+            previewText.setBackgroundDrawable(params.mPreviewBackground);
         }
 
         previewText.measure(MEASURESPEC_UNSPECIFIED, MEASURESPEC_UNSPECIFIED);
         final int previewWidth = Math.max(previewText.getMeasuredWidth(), keyDrawWidth
                 + previewText.getPaddingLeft() + previewText.getPaddingRight());
-        final int previewHeight = mPreviewHeight;
-        getLocationInWindow(mCoordinates);
-        int previewX = keyDrawX - (previewWidth - keyDrawWidth) / 2 + mCoordinates[0];
-        final int previewY = key.mY - previewHeight + mCoordinates[1] + mPreviewOffset;
-        if (previewX < 0 && mPreviewLeftBackground != null) {
-            previewText.setBackgroundDrawable(mPreviewLeftBackground);
+        final int previewHeight = params.mPreviewHeight;
+        getLocationInWindow(params.mCoordinates);
+        int previewX = keyDrawX - (previewWidth - keyDrawWidth) / 2 + params.mCoordinates[0];
+        final int previewY = key.mY - previewHeight
+                + params.mCoordinates[1] + params.mPreviewOffset;
+        if (previewX < 0 && params.mPreviewLeftBackground != null) {
+            previewText.setBackgroundDrawable(params.mPreviewLeftBackground);
             previewX = 0;
-        } else if (previewX + previewWidth > getWidth() && mPreviewRightBackground != null) {
-            previewText.setBackgroundDrawable(mPreviewRightBackground);
+        } else if (previewX + previewWidth > getWidth() && params.mPreviewRightBackground != null) {
+            previewText.setBackgroundDrawable(params.mPreviewRightBackground);
             previewX = getWidth() - previewWidth;
         }
 
         // Set the preview background state
         previewText.getBackground().setState(
                 key.mPopupCharacters != null ? LONG_PRESSABLE_STATE_SET : EMPTY_STATE_SET);
+        previewText.setTextColor(params.mPreviewTextColor);
         FrameLayoutCompatUtils.placeViewAt(
                 previewText, previewX, previewY, previewWidth, previewHeight);
         previewText.setVisibility(VISIBLE);