Add Configuration.getLayoutDirectionFromLocale()

- returns LAYOUT_DIRECTION_UNDEFINED / LAYOUT_DIRECTION_LTR / LAYOUT_DIRECTION_RTL depending on the Locale
- add unit tests

Change-Id: I4372734eb011cbf6270f39ba815e696b04f2352f

2 files changed, 251 insertions, 0 deletions

diff --git a/core/java/android/content/res/Configuration.java b/core/java/android/content/res/Configuration.java
index 6409aac441e7..f51d46e93f4f 100644
--- a/core/java/android/content/res/Configuration.java
+++ b/core/java/android/content/res/Configuration.java
@@ -270,6 +270,26 @@ public final class Configuration implements Parcelable, Comparable<Configuration
     public int smallestScreenWidthDp;
 
     /**
+     * @hide
+     */
+    public static final int LAYOUT_DIRECTION_UNDEFINED = -1;
+
+    /**
+     * @hide
+     */
+    public static final int LAYOUT_DIRECTION_LTR = 0;
+
+    /**
+     * @hide
+     */
+    public static final int LAYOUT_DIRECTION_RTL = 1;
+
+    /**
+     * @hide The layout direction associated to the current Locale
+     */
+    public int layoutDirection;
+
+    /**
      * @hide Internal book-keeping.
      */
     public int seq;
@@ -295,6 +315,7 @@ public final class Configuration implements Parcelable, Comparable<Configuration
         mnc = o.mnc;
         if (o.locale != null) {
             locale = (Locale) o.locale.clone();
+            layoutDirection = o.layoutDirection;
         }
         userSetLocale = o.userSetLocale;
         touchscreen = o.touchscreen;
@@ -419,6 +440,11 @@ public final class Configuration implements Parcelable, Comparable<Configuration
             case NAVIGATIONHIDDEN_YES: sb.append("/h"); break;
             default: sb.append("/"); sb.append(navigationHidden); break;
         }
+        switch (layoutDirection) {
+            case LAYOUT_DIRECTION_UNDEFINED: sb.append(" ?layoutdir"); break;
+            case LAYOUT_DIRECTION_LTR: sb.append(" ltr"); break;
+            case LAYOUT_DIRECTION_RTL: sb.append(" rtl"); break;
+        }
         if (seq != 0) {
             sb.append(" s.");
             sb.append(seq);
@@ -448,6 +474,7 @@ public final class Configuration implements Parcelable, Comparable<Configuration
         screenHeightDp = SCREEN_HEIGHT_DP_UNDEFINED;
         smallestScreenWidthDp = SMALLEST_SCREEN_WIDTH_DP_UNDEFINED;
         seq = 0;
+        layoutDirection = LAYOUT_DIRECTION_LTR;
     }
 
     /** {@hide} */
@@ -482,6 +509,7 @@ public final class Configuration implements Parcelable, Comparable<Configuration
             changed |= ActivityInfo.CONFIG_LOCALE;
             locale = delta.locale != null
                     ? (Locale) delta.locale.clone() : null;
+            layoutDirection = getLayoutDirectionFromLocale(locale);
         }
         if (delta.userSetLocale && (!userSetLocale || ((changed & ActivityInfo.CONFIG_LOCALE) != 0)))
         {
@@ -564,6 +592,29 @@ public final class Configuration implements Parcelable, Comparable<Configuration
     }
 
     /**
+     * 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 #LAYOUT_DIRECTION_UNDEFINED},
+     * {@link #LAYOUT_DIRECTION_LTR} or {@link #LAYOUT_DIRECTION_RTL}.
+     *
+     * @hide
+     */
+    public static int getLayoutDirectionFromLocale(Locale locale) {
+        if (locale == null || locale.equals(Locale.ROOT)) return LAYOUT_DIRECTION_UNDEFINED;
+        // Be careful: this code will need to be changed when vertical scripts will be supported
+        // OR if ICU4C is updated to have the "likelySubtags" file
+        switch(Character.getDirectionality(locale.getDisplayName(locale).charAt(0))) {
+            case Character.DIRECTIONALITY_LEFT_TO_RIGHT:
+                return LAYOUT_DIRECTION_LTR;
+            case Character.DIRECTIONALITY_RIGHT_TO_LEFT:
+            case Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC:
+                return LAYOUT_DIRECTION_RTL;
+            default:
+                return LAYOUT_DIRECTION_UNDEFINED;
+        }
+    }
+
+    /**
      * Return a bit mask of the differences between this Configuration
      * object and the given one.  Does not change the values of either.  Any
      * undefined fields in <var>delta</var> are ignored.
@@ -739,6 +790,7 @@ public final class Configuration implements Parcelable, Comparable<Configuration
         dest.writeInt(screenWidthDp);
         dest.writeInt(screenHeightDp);
         dest.writeInt(smallestScreenWidthDp);
+        dest.writeInt(layoutDirection);
         dest.writeInt(seq);
     }
 
@@ -763,6 +815,7 @@ public final class Configuration implements Parcelable, Comparable<Configuration
         screenWidthDp = source.readInt();
         screenHeightDp = source.readInt();
         smallestScreenWidthDp = source.readInt();
+        layoutDirection = source.readInt();
         seq = source.readInt();
     }
     
diff --git a/core/tests/coretests/src/android/content/res/ConfigurationTest.java b/core/tests/coretests/src/android/content/res/ConfigurationTest.java
new file mode 100644
index 000000000000..f1f745ea9be9
--- /dev/null
+++ b/core/tests/coretests/src/android/content/res/ConfigurationTest.java
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.content.res;
+
+import java.util.Locale;
+
+import android.test.AndroidTestCase;
+import dalvik.annotation.TestLevel;
+import dalvik.annotation.TestTargetNew;
+
+public class ConfigurationTest extends AndroidTestCase {
+
+    @TestTargetNew(
+        level = TestLevel.COMPLETE,
+        method = "getLayoutDirectionFromLocale",
+        args = {Locale.class}
+    )
+    public void testGetLayoutDirectionFromLocale() {
+        assertEquals(Configuration.LAYOUT_DIRECTION_UNDEFINED,
+            Configuration.getLayoutDirectionFromLocale(null));
+
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.ENGLISH));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.CANADA));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.CANADA_FRENCH));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.FRANCE));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.FRENCH));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.GERMAN));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.GERMANY));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.ITALIAN));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.ITALY));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.UK));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.US));
+
+        assertEquals(Configuration.LAYOUT_DIRECTION_UNDEFINED,
+            Configuration.getLayoutDirectionFromLocale(Locale.ROOT));
+
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.CHINA));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.CHINESE));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.JAPAN));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.JAPANESE));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.KOREA));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.KOREAN));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.PRC));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.SIMPLIFIED_CHINESE));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.TAIWAN));
+        assertEquals(Configuration.LAYOUT_DIRECTION_LTR,
+            Configuration.getLayoutDirectionFromLocale(Locale.TRADITIONAL_CHINESE));
+
+        Locale locale = new Locale("ar");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "AE");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "BH");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "DZ");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "EG");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "IQ");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "JO");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "KW");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "LB");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "LY");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "MA");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "OM");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "QA");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "SA");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "SD");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "SY");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "TN");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ar", "YE");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+
+        locale = new Locale("fa");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("fa", "AF");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("fa", "IR");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+
+        locale = new Locale("iw");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("iw", "IL");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("he");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("he", "IL");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+
+        // The following test will not pass until we are able to take care about the scrip subtag
+        // thru having the "likelySubTags" file into ICU4C
+//        locale = new Locale("pa_Arab");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+//        locale = new Locale("pa_Arab", "PK");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+
+        locale = new Locale("ps");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+        locale = new Locale("ps", "AF");
+        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+            Configuration.getLayoutDirectionFromLocale(locale));
+
+        // The following test will not work as the localized display name would be "Urdu" with ICU 4.4
+        // We will need ICU 4.6 to get the correct localized display name
+//        locale = new Locale("ur");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+//        locale = new Locale("ur", "IN");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+//        locale = new Locale("ur", "PK");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+
+        // The following test will not pass until we are able to take care about the scrip subtag
+        // thru having the "likelySubTags" file into ICU4C
+//        locale = new Locale("uz_Arab");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+//        locale = new Locale("uz_Arab", "AF");
+//        assertEquals(Configuration.LAYOUT_DIRECTION_RTL,
+//            Configuration.getLayoutDirectionFromLocale(locale));
+    }
+}