Fix bug #7173351 API REVIEW: android.util.LocaleUtil

Change-Id: I08fd491eff714059e9ec874fadebe7eb556c34d5

Author: Fabrice Di Meglio

api/current.txt

@@ -22033,6 +22033,7 @@ package android.text {
     method public static java.lang.CharSequence expandTemplate(java.lang.CharSequence, java.lang.CharSequence...);
     method public static int getCapsMode(java.lang.CharSequence, int, int);
     method public static void getChars(java.lang.CharSequence, int, int, char[], int);
+    method public static int getLayoutDirectionFromLocale(java.util.Locale);
     method public static int getOffsetAfter(java.lang.CharSequence, int);
     method public static int getOffsetBefore(java.lang.CharSequence, int);
     method public static java.lang.CharSequence getReverse(java.lang.CharSequence, int, int);
@@ -23127,10 +23128,6 @@ package android.util {
     method public android.util.JsonWriter value(java.lang.Number) throws java.io.IOException;
   }
 
-  public class LocaleUtil {
-    method public static int getLayoutDirectionFromLocale(java.util.Locale);
-  }
-
   public final class Log {
     method public static int d(java.lang.String, java.lang.String);
     method public static int d(java.lang.String, java.lang.String, java.lang.Throwable);

core/java/android/content/res/Configuration.java

@@ -19,7 +19,7 @@
 import android.content.pm.ActivityInfo;
 import android.os.Parcel;
 import android.os.Parcelable;
-import android.util.LocaleUtil;
+import android.text.TextUtils;
 import android.view.View;
 
 import java.util.Locale;
@@ -1169,7 +1169,7 @@ public int getLayoutDirection() {
     public void setLayoutDirection(Locale locale) {
         // There is a "1" difference between the configuration values for
         // layout direction and View constants for layout direction, just add "1".
-        final int layoutDirection = 1 + LocaleUtil.getLayoutDirectionFromLocale(locale);
+        final int layoutDirection = 1 + TextUtils.getLayoutDirectionFromLocale(locale);
         screenLayout = (screenLayout&~SCREENLAYOUT_LAYOUTDIR_MASK)|
                 (layoutDirection << SCREENLAYOUT_LAYOUTDIR_SHIFT);
     }

core/java/android/text/TextDirectionHeuristics.java

@@ -17,7 +17,6 @@
 package android.text;
 
 
-import android.util.LocaleUtil;
 import android.view.View;
 
 /**
@@ -242,7 +241,7 @@ public TextDirectionHeuristicLocale() {
 
         @Override
         protected boolean defaultIsRtl() {
-            final int dir = LocaleUtil.getLayoutDirectionFromLocale(java.util.Locale.getDefault());
+            final int dir = TextUtils.getLayoutDirectionFromLocale(java.util.Locale.getDefault());
             return (dir == View.LAYOUT_DIRECTION_RTL);
         }
 

core/java/android/text/TextUtils.java

@@ -46,11 +46,14 @@
 import android.text.style.UnderlineSpan;
 import android.util.Printer;
 
+import android.view.View;
 import com.android.internal.R;
 import com.android.internal.util.ArrayUtils;
+import libcore.icu.ICU;
 
 import java.lang.reflect.Array;
 import java.util.Iterator;
+import java.util.Locale;
 import java.util.regex.Pattern;
 
 public class TextUtils {
@@ -1706,10 +1709,64 @@ public static int unpackRangeEndFromLong(long range) {
         return (int) (range & 0x00000000FFFFFFFFL);
     }
 
+    /**
+     * Return the layout direction for a given Locale
+     *
+     * @param locale the Locale for which we want the layout direction. Can be null.
+     * @return the layout direction. This may be one of:
+     * {@link android.view.View#LAYOUT_DIRECTION_LTR} or
+     * {@link android.view.View#LAYOUT_DIRECTION_RTL}.
+     *
+     * Be careful: this code will need to be updated when vertical scripts will be supported
+     */
+    public static int getLayoutDirectionFromLocale(Locale locale) {
+        if (locale != null && !locale.equals(Locale.ROOT)) {
+            final String scriptSubtag = ICU.getScript(ICU.addLikelySubtags(locale.toString()));
+            if (scriptSubtag == null) return getLayoutDirectionFromFirstChar(locale);
+
+            if (scriptSubtag.equalsIgnoreCase(ARAB_SCRIPT_SUBTAG) ||
+                    scriptSubtag.equalsIgnoreCase(HEBR_SCRIPT_SUBTAG)) {
+                return View.LAYOUT_DIRECTION_RTL;
+            }
+        }
+
+        return View.LAYOUT_DIRECTION_LTR;
+    }
+
+    /**
+     * Fallback algorithm to detect the locale direction. Rely on the fist char of the
+     * localized locale name. This will not work if the localized locale name is in English
+     * (this is the case for ICU 4.4 and "Urdu" script)
+     *
+     * @param locale
+     * @return the layout direction. This may be one of:
+     * {@link View#LAYOUT_DIRECTION_LTR} or
+     * {@link View#LAYOUT_DIRECTION_RTL}.
+     *
+     * Be careful: this code will need to be updated when vertical scripts will be supported
+     *
+     * @hide
+     */
+    private static int getLayoutDirectionFromFirstChar(Locale locale) {
+        switch(Character.getDirectionality(locale.getDisplayName(locale).charAt(0))) {
+            case Character.DIRECTIONALITY_RIGHT_TO_LEFT:
+            case Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC:
+                return View.LAYOUT_DIRECTION_RTL;
+
+            case Character.DIRECTIONALITY_LEFT_TO_RIGHT:
+            default:
+                return View.LAYOUT_DIRECTION_LTR;
+        }
+    }
+
     private static Object sLock = new Object();
+
     private static char[] sTemp = null;
 
     private static String[] EMPTY_STRING_ARRAY = new String[]{};
 
     private static final char ZWNBS_CHAR = '\uFEFF';
+
+    private static String ARAB_SCRIPT_SUBTAG = "Arab";
+    private static String HEBR_SCRIPT_SUBTAG = "Hebr";
 }

core/java/android/util/LocaleUtil.java

@@ -48,9 +48,9 @@
 import android.os.RemoteException;
 import android.os.SystemClock;
 import android.os.SystemProperties;
+import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.FloatProperty;
-import android.util.LocaleUtil;
 import android.util.Log;
 import android.util.Pool;
 import android.util.Poolable;
@@ -11582,7 +11582,7 @@ public void onResolvedLayoutDirectionReset() {
      * @return true if the Locale uses an RTL script.
      */
     protected static boolean isLayoutDirectionRtl(Locale locale) {
-        return (LAYOUT_DIRECTION_RTL == LocaleUtil.getLayoutDirectionFromLocale(locale));
+        return (LAYOUT_DIRECTION_RTL == TextUtils.getLayoutDirectionFromLocale(locale));
     }
 
     /**

core/java/android/view/View.java

@@ -21,8 +21,8 @@
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.os.Handler;
+import android.text.TextUtils;
 import android.util.AttributeSet;
-import android.util.LocaleUtil;
 import android.util.Log;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
@@ -200,7 +200,7 @@ public ListPopupWindow(Context context, AttributeSet attrs, int defStyleAttr, in
         mPopup.setInputMethodMode(PopupWindow.INPUT_METHOD_NEEDED);
         // Set the default layout direction to match the default locale one
         final Locale locale = mContext.getResources().getConfiguration().locale;
-        mLayoutDirection = LocaleUtil.getLayoutDirectionFromLocale(locale);
+        mLayoutDirection = TextUtils.getLayoutDirectionFromLocale(locale);
     }
 
     /**