1/* 2 * Copyright (C) 2006 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 17package android.text.style; 18 19import android.graphics.Paint; 20import android.graphics.Typeface; 21import android.os.Parcel; 22import android.text.ParcelableSpan; 23import android.text.TextPaint; 24import android.text.TextUtils; 25 26/** 27 * 28 * Describes a style in a span. 29 * Note that styles are cumulative -- if both bold and italic are set in 30 * separate spans, or if the base style is bold and a span calls for italic, 31 * you get bold italic. You can't turn off a style from the base style. 32 * 33 */ 34public class StyleSpan extends MetricAffectingSpan implements ParcelableSpan { 35 36 private final int mStyle; 37 38 /** 39 * 40 * @param style An integer constant describing the style for this span. Examples 41 * include bold, italic, and normal. Values are constants defined 42 * in {@link android.graphics.Typeface}. 43 */ 44 public StyleSpan(int style) { 45 mStyle = style; 46 } 47 48 public StyleSpan(Parcel src) { 49 mStyle = src.readInt(); 50 } 51 52 public int getSpanTypeId() { 53 return TextUtils.STYLE_SPAN; 54 } 55 56 public int describeContents() { 57 return 0; 58 } 59 60 public void writeToParcel(Parcel dest, int flags) { 61 dest.writeInt(mStyle); 62 } 63 64 /** 65 * Returns the style constant defined in {@link android.graphics.Typeface}. 66 */ 67 public int getStyle() { 68 return mStyle; 69 } 70 71 @Override 72 public void updateDrawState(TextPaint ds) { 73 apply(ds, mStyle); 74 } 75 76 @Override 77 public void updateMeasureState(TextPaint paint) { 78 apply(paint, mStyle); 79 } 80 81 private static void apply(Paint paint, int style) { 82 int oldStyle; 83 84 Typeface old = paint.getTypeface(); 85 if (old == null) { 86 oldStyle = 0; 87 } else { 88 oldStyle = old.getStyle(); 89 } 90 91 int want = oldStyle | style; 92 93 Typeface tf; 94 if (old == null) { 95 tf = Typeface.defaultFromStyle(want); 96 } else { 97 tf = Typeface.create(old, want); 98 } 99 100 int fake = want & ~tf.getStyle(); 101 102 if ((fake & Typeface.BOLD) != 0) { 103 paint.setFakeBoldText(true); 104 } 105 106 if ((fake & Typeface.ITALIC) != 0) { 107 paint.setTextSkewX(-0.25f); 108 } 109 110 paint.setTypeface(tf); 111 } 112} 113