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