1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.text.style; 18 19 import android.annotation.NonNull; 20 import android.annotation.Nullable; 21 import android.graphics.Paint; 22 import android.os.LocaleList; 23 import android.os.Parcel; 24 import android.text.ParcelableSpan; 25 import android.text.TextPaint; 26 import android.text.TextUtils; 27 28 import com.android.internal.util.Preconditions; 29 30 import java.util.Locale; 31 32 /** 33 * Changes the {@link Locale} of the text to which the span is attached. 34 */ 35 public class LocaleSpan extends MetricAffectingSpan implements ParcelableSpan { 36 @NonNull 37 private final LocaleList mLocales; 38 39 /** 40 * Creates a {@link LocaleSpan} from a well-formed {@link Locale}. Note that only 41 * {@link Locale} objects that can be created by {@link Locale#forLanguageTag(String)} are 42 * supported. 43 * 44 * <p><b>Caveat:</b> Do not specify any {@link Locale} object that cannot be created by 45 * {@link Locale#forLanguageTag(String)}. {@code new Locale(" a ", " b c", " d")} is an 46 * example of such a malformed {@link Locale} object.</p> 47 * 48 * @param locale The {@link Locale} of the text to which the span is attached. 49 * 50 * @see #LocaleSpan(LocaleList) 51 */ 52 public LocaleSpan(@Nullable Locale locale) { 53 mLocales = locale == null ? LocaleList.getEmptyLocaleList() : new LocaleList(locale); 54 } 55 56 /** 57 * Creates a {@link LocaleSpan} from {@link LocaleList}. 58 * 59 * @param locales The {@link LocaleList} of the text to which the span is attached. 60 * @throws NullPointerException if {@code locales} is null 61 */ 62 public LocaleSpan(@NonNull LocaleList locales) { 63 Preconditions.checkNotNull(locales, "locales cannot be null"); 64 mLocales = locales; 65 } 66 67 public LocaleSpan(Parcel source) { 68 mLocales = LocaleList.CREATOR.createFromParcel(source); 69 } 70 71 @Override 72 public int getSpanTypeId() { 73 return getSpanTypeIdInternal(); 74 } 75 76 /** @hide */ 77 public int getSpanTypeIdInternal() { 78 return TextUtils.LOCALE_SPAN; 79 } 80 81 @Override 82 public int describeContents() { 83 return 0; 84 } 85 86 @Override 87 public void writeToParcel(Parcel dest, int flags) { 88 writeToParcelInternal(dest, flags); 89 } 90 91 /** @hide */ 92 public void writeToParcelInternal(Parcel dest, int flags) { 93 mLocales.writeToParcel(dest, flags); 94 } 95 96 /** 97 * @return The {@link Locale} for this span. If multiple locales are associated with this 98 * span, only the first locale is returned. {@code null} if no {@link Locale} is specified. 99 * 100 * @see LocaleList#get() 101 * @see #getLocales() 102 */ 103 @Nullable 104 public Locale getLocale() { 105 return mLocales.get(0); 106 } 107 108 /** 109 * @return The entire list of locales that are associated with this span. 110 */ 111 @NonNull 112 public LocaleList getLocales() { 113 return mLocales; 114 } 115 116 @Override 117 public void updateDrawState(TextPaint ds) { 118 apply(ds, mLocales); 119 } 120 121 @Override 122 public void updateMeasureState(TextPaint paint) { 123 apply(paint, mLocales); 124 } 125 126 private static void apply(@NonNull Paint paint, @NonNull LocaleList locales) { 127 paint.setTextLocales(locales); 128 } 129 } 130