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 17 package android.text; 18 19 /** 20 * This is the interface for text that has markup objects attached to 21 * ranges of it. Not all text classes have mutable markup or text; 22 * see {@link Spannable} for mutable markup and {@link Editable} for 23 * mutable text. 24 */ 25 @android.ravenwood.annotation.RavenwoodKeepWholeClass 26 public interface Spanned 27 extends CharSequence 28 { 29 /** 30 * Bitmask of bits that are relevent for controlling point/mark behavior 31 * of spans. 32 * 33 * MARK and POINT are conceptually located <i>between</i> two adjacent characters. 34 * A MARK is "attached" to the character before, while a POINT will stick to the character 35 * after. The insertion cursor is conceptually located between the MARK and the POINT. 36 * 37 * As a result, inserting a new character between a MARK and a POINT will leave the MARK 38 * unchanged, while the POINT will be shifted, now located after the inserted character and 39 * still glued to the same character after it. 40 * 41 * Depending on whether the insertion happens at the beginning or the end of a span, the span 42 * will hence be expanded to <i>include</i> the new character (when the span is using a MARK at 43 * its beginning or a POINT at its end) or it will be <i>excluded</i>. 44 * 45 * Note that <i>before</i> and <i>after</i> here refer to offsets in the String, which are 46 * independent from the visual representation of the text (left-to-right or right-to-left). 47 */ 48 public static final int SPAN_POINT_MARK_MASK = 0x33; 49 50 /** 51 * 0-length spans with type SPAN_MARK_MARK behave like text marks: 52 * they remain at their original offset when text is inserted 53 * at that offset. Conceptually, the text is added after the mark. 54 */ 55 public static final int SPAN_MARK_MARK = 0x11; 56 /** 57 * SPAN_MARK_POINT is a synonym for {@link #SPAN_INCLUSIVE_INCLUSIVE}. 58 */ 59 public static final int SPAN_MARK_POINT = 0x12; 60 /** 61 * SPAN_POINT_MARK is a synonym for {@link #SPAN_EXCLUSIVE_EXCLUSIVE}. 62 */ 63 public static final int SPAN_POINT_MARK = 0x21; 64 65 /** 66 * 0-length spans with type SPAN_POINT_POINT behave like cursors: 67 * they are pushed forward by the length of the insertion when text 68 * is inserted at their offset. 69 * The text is conceptually inserted before the point. 70 */ 71 public static final int SPAN_POINT_POINT = 0x22; 72 73 /** 74 * SPAN_PARAGRAPH behaves like SPAN_INCLUSIVE_EXCLUSIVE 75 * (SPAN_MARK_MARK), except that if either end of the span is 76 * at the end of the buffer, that end behaves like _POINT 77 * instead (so SPAN_INCLUSIVE_INCLUSIVE if it starts in the 78 * middle and ends at the end, or SPAN_EXCLUSIVE_INCLUSIVE 79 * if it both starts and ends at the end). 80 * <p> 81 * Its endpoints must be the start or end of the buffer or 82 * immediately after a \n character, and if the \n 83 * that anchors it is deleted, the endpoint is pulled to the 84 * next \n that follows in the buffer (or to the end of 85 * the buffer). If a span with SPAN_PARAGRAPH flag is pasted 86 * into another text and the paragraph boundary constraint 87 * is not satisfied, the span is discarded. 88 */ 89 public static final int SPAN_PARAGRAPH = 0x33; 90 91 /** 92 * Non-0-length spans of type SPAN_INCLUSIVE_EXCLUSIVE expand 93 * to include text inserted at their starting point but not at their 94 * ending point. When 0-length, they behave like marks. 95 */ 96 public static final int SPAN_INCLUSIVE_EXCLUSIVE = SPAN_MARK_MARK; 97 98 /** 99 * Spans of type SPAN_INCLUSIVE_INCLUSIVE expand 100 * to include text inserted at either their starting or ending point. 101 */ 102 public static final int SPAN_INCLUSIVE_INCLUSIVE = SPAN_MARK_POINT; 103 104 /** 105 * Spans of type SPAN_EXCLUSIVE_EXCLUSIVE do not expand 106 * to include text inserted at either their starting or ending point. 107 * They can never have a length of 0 and are automatically removed 108 * from the buffer if all the text they cover is removed. 109 */ 110 public static final int SPAN_EXCLUSIVE_EXCLUSIVE = SPAN_POINT_MARK; 111 112 /** 113 * Non-0-length spans of type SPAN_EXCLUSIVE_INCLUSIVE expand 114 * to include text inserted at their ending point but not at their 115 * starting point. When 0-length, they behave like points. 116 */ 117 public static final int SPAN_EXCLUSIVE_INCLUSIVE = SPAN_POINT_POINT; 118 119 /** 120 * This flag is set on spans that are being used to apply temporary 121 * styling information on the composing text of an input method, so that 122 * they can be found and removed when the composing text is being 123 * replaced. 124 */ 125 public static final int SPAN_COMPOSING = 0x100; 126 127 /** 128 * This flag will be set for intermediate span changes, meaning there 129 * is guaranteed to be another change following it. Typically it is 130 * used for {@link Selection} which automatically uses this with the first 131 * offset it sets when updating the selection. 132 */ 133 public static final int SPAN_INTERMEDIATE = 0x200; 134 135 /** 136 * The bits numbered SPAN_USER_SHIFT and above are available 137 * for callers to use to store scalar data associated with their 138 * span object. 139 */ 140 public static final int SPAN_USER_SHIFT = 24; 141 /** 142 * The bits specified by the SPAN_USER bitfield are available 143 * for callers to use to store scalar data associated with their 144 * span object. 145 */ 146 public static final int SPAN_USER = 0xFFFFFFFF << SPAN_USER_SHIFT; 147 148 /** 149 * The bits numbered just above SPAN_PRIORITY_SHIFT determine the order 150 * of change notifications -- higher numbers go first. You probably 151 * don't need to set this; it is used so that when text changes, the 152 * text layout gets the chance to update itself before any other 153 * callbacks can inquire about the layout of the text. 154 */ 155 public static final int SPAN_PRIORITY_SHIFT = 16; 156 /** 157 * The bits specified by the SPAN_PRIORITY bitmap determine the order 158 * of change notifications -- higher numbers go first. You probably 159 * don't need to set this; it is used so that when text changes, the 160 * text layout gets the chance to update itself before any other 161 * callbacks can inquire about the layout of the text. 162 */ 163 public static final int SPAN_PRIORITY = 0xFF << SPAN_PRIORITY_SHIFT; 164 165 /** 166 * Return an array of the markup objects attached to the specified 167 * slice of this CharSequence and whose type is the specified type 168 * or a subclass of it. Specify Object.class for the type if you 169 * want all the objects regardless of type. 170 */ getSpans(int start, int end, Class<T> type)171 public <T> T[] getSpans(int start, int end, Class<T> type); 172 173 /** 174 * Return the beginning of the range of text to which the specified 175 * markup object is attached, or -1 if the object is not attached. 176 */ getSpanStart(Object tag)177 public int getSpanStart(Object tag); 178 179 /** 180 * Return the end of the range of text to which the specified 181 * markup object is attached, or -1 if the object is not attached. 182 */ getSpanEnd(Object tag)183 public int getSpanEnd(Object tag); 184 185 /** 186 * Return the flags that were specified when {@link Spannable#setSpan} was 187 * used to attach the specified markup object, or 0 if the specified 188 * object has not been attached. 189 */ getSpanFlags(Object tag)190 public int getSpanFlags(Object tag); 191 192 /** 193 * Return the first offset greater than <code>start</code> where a markup 194 * object of class <code>type</code> begins or ends, or <code>limit</code> 195 * if there are no starts or ends greater than <code>start</code> but less 196 * than <code>limit</code>. Specify <code>null</code> or Object.class for 197 * the type if you want every transition regardless of type. 198 */ nextSpanTransition(int start, int limit, Class type)199 public int nextSpanTransition(int start, int limit, Class type); 200 } 201