| /* |
| * 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.util; |
| |
| import java.util.Locale; |
| |
| import libcore.icu.ICU; |
| |
| /** |
| * Various utilities for Locales |
| * |
| * @hide |
| */ |
| public class LocaleUtil { |
| |
| private LocaleUtil() { /* cannot be instantiated */ } |
| |
| /** |
| * @hide Do not use. Implementation not finished. |
| */ |
| public static final int TEXT_LAYOUT_DIRECTION_UNDEFINED_DO_NOT_USE = -1; |
| |
| /** |
| * @hide Do not use. Implementation not finished. |
| */ |
| public static final int TEXT_LAYOUT_DIRECTION_LTR_DO_NOT_USE = 0; |
| |
| /** |
| * @hide Do not use. Implementation not finished. |
| */ |
| public static final int TEXT_LAYOUT_DIRECTION_RTL_DO_NOT_USE = 1; |
| |
| private static final char UNDERSCORE_CHAR = '_'; |
| |
| private static String ARAB_SCRIPT_SUBTAG = "Arab"; |
| private static String HEBR_SCRIPT_SUBTAG = "Hebr"; |
| |
| /** |
| * 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 #TEXT_LAYOUT_DIRECTION_UNDEFINED_DO_NOT_USE} or |
| * {@link #TEXT_LAYOUT_DIRECTION_LTR_DO_NOT_USE} or |
| * {@link #TEXT_LAYOUT_DIRECTION_RTL_DO_NOT_USE}. |
| * |
| * Be careful: this code will need to be changed when vertical scripts will be supported |
| * |
| * @hide |
| */ |
| public static int getLayoutDirectionFromLocale(Locale locale) { |
| if (locale == null || locale.equals(Locale.ROOT)) { |
| return TEXT_LAYOUT_DIRECTION_UNDEFINED_DO_NOT_USE; |
| } |
| |
| 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 TEXT_LAYOUT_DIRECTION_RTL_DO_NOT_USE; |
| } |
| return TEXT_LAYOUT_DIRECTION_LTR_DO_NOT_USE; |
| } |
| |
| /** |
| * 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 #TEXT_LAYOUT_DIRECTION_UNDEFINED_DO_NOT_USE} or |
| * {@link #TEXT_LAYOUT_DIRECTION_LTR_DO_NOT_USE} or |
| * {@link #TEXT_LAYOUT_DIRECTION_RTL_DO_NOT_USE}. |
| * |
| * Be careful: this code will need to be changed when vertical scripts will be supported |
| * |
| * @hide |
| */ |
| private static int getLayoutDirectionFromFirstChar(Locale locale) { |
| switch(Character.getDirectionality(locale.getDisplayName(locale).charAt(0))) { |
| case Character.DIRECTIONALITY_LEFT_TO_RIGHT: |
| return TEXT_LAYOUT_DIRECTION_LTR_DO_NOT_USE; |
| case Character.DIRECTIONALITY_RIGHT_TO_LEFT: |
| case Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC: |
| return TEXT_LAYOUT_DIRECTION_RTL_DO_NOT_USE; |
| default: |
| return TEXT_LAYOUT_DIRECTION_UNDEFINED_DO_NOT_USE; |
| } |
| } |
| } |