Add lightweight visual indication for numbers.

This change adds lightweight visual hints of alternate numeric characters on the top row - e.g. having a light gray '1' on the upper right corner of letter 'q'

Note that MDPI resources are tentative (the same as HDPI for now, until we get fixed MDPI visual assets).

bug: 3004632
Change-Id: I7a25cf90b702433a844c88f5c47bf914706af9bc

1 files changed, 44 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/latin/LatinKeyboard.java b/java/src/com/android/inputmethod/latin/LatinKeyboard.java
index 4e139e849..8b89f3900 100644
--- a/java/src/com/android/inputmethod/latin/LatinKeyboard.java
+++ b/java/src/com/android/inputmethod/latin/LatinKeyboard.java
@@ -63,6 +63,9 @@ public class LatinKeyboard extends Keyboard {
     private Key mF1Key;
     private Key mSpaceKey;
     private Key m123Key;
+    private final int NUMBER_HINT_COUNT = 10;
+    private Key[] mNumberHintKeys;
+    private Drawable[] mNumberHintIcons = new Drawable[NUMBER_HINT_COUNT];
     private int mSpaceKeyIndex = -1;
     private int mSpaceDragStartX;
     private int mSpaceDragLastDiff;
@@ -129,6 +132,21 @@ public class LatinKeyboard extends Keyboard {
         mIsAlphaKeyboard = xmlLayoutResId == R.xml.kbd_qwerty
                 || xmlLayoutResId == R.xml.kbd_qwerty_black;
         mSpaceKeyIndex = indexOf(' ');
+        initializeNumberHintResources(context);
+    }
+
+    private void initializeNumberHintResources(Context context) {
+        final Resources res = context.getResources();
+        mNumberHintIcons[0] = res.getDrawable(R.drawable.keyboard_hint_0);
+        mNumberHintIcons[1] = res.getDrawable(R.drawable.keyboard_hint_1);
+        mNumberHintIcons[2] = res.getDrawable(R.drawable.keyboard_hint_2);
+        mNumberHintIcons[3] = res.getDrawable(R.drawable.keyboard_hint_3);
+        mNumberHintIcons[4] = res.getDrawable(R.drawable.keyboard_hint_4);
+        mNumberHintIcons[5] = res.getDrawable(R.drawable.keyboard_hint_5);
+        mNumberHintIcons[6] = res.getDrawable(R.drawable.keyboard_hint_6);
+        mNumberHintIcons[7] = res.getDrawable(R.drawable.keyboard_hint_7);
+        mNumberHintIcons[8] = res.getDrawable(R.drawable.keyboard_hint_8);
+        mNumberHintIcons[9] = res.getDrawable(R.drawable.keyboard_hint_9);
     }
 
     @Override
@@ -150,6 +168,23 @@ public class LatinKeyboard extends Keyboard {
             m123Label = key.label;
             break;
         }
+
+        // For number hints on the upper-right corner of key
+        if (mNumberHintKeys == null) {
+            // NOTE: This protected method is being called from the base class constructor before
+            // mNumberHintKeys gets initialized.
+            mNumberHintKeys = new Key[NUMBER_HINT_COUNT];
+        }
+        int hintNumber = -1;
+        if (LatinKeyboardBaseView.isNumberAtLeftmostPopupChar(key)) {
+            hintNumber = key.popupCharacters.charAt(0) - '0';
+        } else if (LatinKeyboardBaseView.isNumberAtRightmostPopupChar(key)) {
+            hintNumber = key.popupCharacters.charAt(key.popupCharacters.length() - 1) - '0';
+        }
+        if (hintNumber >= 0 && hintNumber <= 9) {
+            mNumberHintKeys[hintNumber] = key;
+        }
+
         return key;
     }
 
@@ -293,6 +328,7 @@ public class LatinKeyboard extends Keyboard {
         if (mSpaceKey != null) {
             updateSpaceBarForLocale(isAutoCompletion, isBlack);
         }
+        updateNumberHintKeys();
     }
 
     private void setDefaultBounds(Drawable drawable) {
@@ -340,6 +376,14 @@ public class LatinKeyboard extends Keyboard {
         return mSpaceKey;
     }
 
+    private void updateNumberHintKeys() {
+        for (int i = 0; i < mNumberHintKeys.length; ++i) {
+            if (mNumberHintKeys[i] != null) {
+                mNumberHintKeys[i].icon = mNumberHintIcons[i];
+            }
+        }
+    }
+
     private void updateSpaceBarForLocale(boolean isAutoCompletion, boolean isBlack) {
         // If application locales are explicitly selected.
         if (mLocale != null) {