The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 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 | |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 19 | import android.annotation.TestApi; |
| 20 | |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 21 | import java.text.BreakIterator; |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 22 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 23 | |
| 24 | /** |
| 25 | * Utility class for manipulating cursors and selections in CharSequences. |
| 26 | * A cursor is a selection where the start and end are at the same offset. |
| 27 | */ |
| 28 | public class Selection { |
| 29 | private Selection() { /* cannot be instantiated */ } |
| 30 | |
| 31 | /* |
| 32 | * Retrieving the selection |
| 33 | */ |
| 34 | |
| 35 | /** |
| 36 | * Return the offset of the selection anchor or cursor, or -1 if |
| 37 | * there is no selection or cursor. |
| 38 | */ |
| 39 | public static final int getSelectionStart(CharSequence text) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 40 | if (text instanceof Spanned) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 41 | return ((Spanned) text).getSpanStart(SELECTION_START); |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 42 | } |
| 43 | return -1; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 44 | } |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 45 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 46 | /** |
| 47 | * Return the offset of the selection edge or cursor, or -1 if |
| 48 | * there is no selection or cursor. |
| 49 | */ |
| 50 | public static final int getSelectionEnd(CharSequence text) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 51 | if (text instanceof Spanned) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 52 | return ((Spanned) text).getSpanStart(SELECTION_END); |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 53 | } |
| 54 | return -1; |
| 55 | } |
| 56 | |
| 57 | private static int getSelectionMemory(CharSequence text) { |
| 58 | if (text instanceof Spanned) { |
| 59 | return ((Spanned) text).getSpanStart(SELECTION_MEMORY); |
| 60 | } |
| 61 | return -1; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 62 | } |
| 63 | |
| 64 | /* |
| 65 | * Setting the selection |
| 66 | */ |
| 67 | |
| 68 | // private static int pin(int value, int min, int max) { |
| 69 | // return value < min ? 0 : (value > max ? max : value); |
| 70 | // } |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 71 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 72 | /** |
| 73 | * Set the selection anchor to <code>start</code> and the selection edge |
| 74 | * to <code>stop</code>. |
| 75 | */ |
| 76 | public static void setSelection(Spannable text, int start, int stop) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 77 | setSelection(text, start, stop, -1); |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * Set the selection anchor to <code>start</code>, the selection edge |
| 82 | * to <code>stop</code> and the memory horizontal to <code>memory</code>. |
| 83 | */ |
| 84 | private static void setSelection(Spannable text, int start, int stop, int memory) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 85 | // int len = text.length(); |
| 86 | // start = pin(start, 0, len); XXX remove unless we really need it |
| 87 | // stop = pin(stop, 0, len); |
| 88 | |
| 89 | int ostart = getSelectionStart(text); |
| 90 | int oend = getSelectionEnd(text); |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 91 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 92 | if (ostart != start || oend != stop) { |
| 93 | text.setSpan(SELECTION_START, start, start, |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 94 | Spanned.SPAN_POINT_POINT | Spanned.SPAN_INTERMEDIATE); |
| 95 | text.setSpan(SELECTION_END, stop, stop, Spanned.SPAN_POINT_POINT); |
| 96 | updateMemory(text, memory); |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * Update the memory position for text. This is used to ensure vertical navigation of lines |
| 102 | * with different lengths behaves as expected and remembers the longest horizontal position |
| 103 | * seen during a vertical traversal. |
| 104 | */ |
| 105 | private static void updateMemory(Spannable text, int memory) { |
| 106 | if (memory > -1) { |
| 107 | int currentMemory = getSelectionMemory(text); |
| 108 | if (memory != currentMemory) { |
| 109 | text.setSpan(SELECTION_MEMORY, memory, memory, Spanned.SPAN_POINT_POINT); |
| 110 | if (currentMemory == -1) { |
| 111 | // This is the first value, create a watcher. |
| 112 | final TextWatcher watcher = new MemoryTextWatcher(); |
| 113 | text.setSpan(watcher, 0, text.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE); |
| 114 | } |
| 115 | } |
| 116 | } else { |
| 117 | removeMemory(text); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | private static void removeMemory(Spannable text) { |
| 122 | text.removeSpan(SELECTION_MEMORY); |
| 123 | MemoryTextWatcher[] watchers = text.getSpans(0, text.length(), MemoryTextWatcher.class); |
| 124 | for (MemoryTextWatcher watcher : watchers) { |
| 125 | text.removeSpan(watcher); |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * @hide |
| 131 | */ |
| 132 | @TestApi |
| 133 | public static final class MemoryTextWatcher implements TextWatcher { |
| 134 | |
| 135 | @Override |
| 136 | public void beforeTextChanged(CharSequence s, int start, int count, int after) {} |
| 137 | |
| 138 | @Override |
| 139 | public void onTextChanged(CharSequence s, int start, int before, int count) {} |
| 140 | |
| 141 | @Override |
| 142 | public void afterTextChanged(Editable s) { |
| 143 | s.removeSpan(SELECTION_MEMORY); |
| 144 | s.removeSpan(this); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 145 | } |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Move the cursor to offset <code>index</code>. |
| 150 | */ |
| 151 | public static final void setSelection(Spannable text, int index) { |
| 152 | setSelection(text, index, index); |
| 153 | } |
| 154 | |
| 155 | /** |
| 156 | * Select the entire text. |
| 157 | */ |
| 158 | public static final void selectAll(Spannable text) { |
| 159 | setSelection(text, 0, text.length()); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Move the selection edge to offset <code>index</code>. |
| 164 | */ |
| 165 | public static final void extendSelection(Spannable text, int index) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 166 | extendSelection(text, index, -1); |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | * Move the selection edge to offset <code>index</code> and update the memory horizontal. |
| 171 | */ |
| 172 | private static void extendSelection(Spannable text, int index, int memory) { |
| 173 | if (text.getSpanStart(SELECTION_END) != index) { |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 174 | text.setSpan(SELECTION_END, index, index, Spanned.SPAN_POINT_POINT); |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 175 | } |
| 176 | updateMemory(text, memory); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 177 | } |
| 178 | |
| 179 | /** |
| 180 | * Remove the selection or cursor, if any, from the text. |
| 181 | */ |
| 182 | public static final void removeSelection(Spannable text) { |
Clara Bayarri | 4e51877 | 2018-03-27 14:25:33 +0100 | [diff] [blame^] | 183 | text.removeSpan(SELECTION_START, Spanned.SPAN_INTERMEDIATE); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 184 | text.removeSpan(SELECTION_END); |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 185 | removeMemory(text); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 186 | } |
| 187 | |
| 188 | /* |
| 189 | * Moving the selection within the layout |
| 190 | */ |
| 191 | |
| 192 | /** |
| 193 | * Move the cursor to the buffer offset physically above the current |
Raph Levien | fb0431b | 2014-09-04 15:03:14 -0700 | [diff] [blame] | 194 | * offset, to the beginning if it is on the top line but not at the |
| 195 | * start, or return false if the cursor is already on the top line. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 196 | */ |
| 197 | public static boolean moveUp(Spannable text, Layout layout) { |
| 198 | int start = getSelectionStart(text); |
| 199 | int end = getSelectionEnd(text); |
| 200 | |
| 201 | if (start != end) { |
| 202 | int min = Math.min(start, end); |
| 203 | int max = Math.max(start, end); |
| 204 | |
| 205 | setSelection(text, min); |
| 206 | |
| 207 | if (min == 0 && max == text.length()) { |
| 208 | return false; |
| 209 | } |
| 210 | |
| 211 | return true; |
| 212 | } else { |
| 213 | int line = layout.getLineForOffset(end); |
| 214 | |
| 215 | if (line > 0) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 216 | setSelectionAndMemory( |
| 217 | text, layout, line, end, -1 /* direction */, false /* extend */); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 218 | return true; |
Raph Levien | fb0431b | 2014-09-04 15:03:14 -0700 | [diff] [blame] | 219 | } else if (end != 0) { |
| 220 | setSelection(text, 0); |
| 221 | return true; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 222 | } |
| 223 | } |
| 224 | |
| 225 | return false; |
| 226 | } |
| 227 | |
| 228 | /** |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 229 | * Calculate the movement and memory positions needed, and set or extend the selection. |
| 230 | */ |
| 231 | private static void setSelectionAndMemory(Spannable text, Layout layout, int line, int end, |
| 232 | int direction, boolean extend) { |
| 233 | int move; |
| 234 | int newMemory; |
| 235 | |
| 236 | if (layout.getParagraphDirection(line) |
| 237 | == layout.getParagraphDirection(line + direction)) { |
| 238 | int memory = getSelectionMemory(text); |
| 239 | if (memory > -1) { |
| 240 | // We have a memory position |
| 241 | float h = layout.getPrimaryHorizontal(memory); |
| 242 | move = layout.getOffsetForHorizontal(line + direction, h); |
| 243 | newMemory = memory; |
| 244 | } else { |
| 245 | // Create a new memory position |
| 246 | float h = layout.getPrimaryHorizontal(end); |
| 247 | move = layout.getOffsetForHorizontal(line + direction, h); |
| 248 | newMemory = end; |
| 249 | } |
| 250 | } else { |
| 251 | move = layout.getLineStart(line + direction); |
| 252 | newMemory = -1; |
| 253 | } |
| 254 | |
| 255 | if (extend) { |
| 256 | extendSelection(text, move, newMemory); |
| 257 | } else { |
| 258 | setSelection(text, move, move, newMemory); |
| 259 | } |
| 260 | } |
| 261 | |
| 262 | /** |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 263 | * Move the cursor to the buffer offset physically below the current |
Raph Levien | fb0431b | 2014-09-04 15:03:14 -0700 | [diff] [blame] | 264 | * offset, to the end of the buffer if it is on the bottom line but |
| 265 | * not at the end, or return false if the cursor is already at the |
| 266 | * end of the buffer. |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 267 | */ |
| 268 | public static boolean moveDown(Spannable text, Layout layout) { |
| 269 | int start = getSelectionStart(text); |
| 270 | int end = getSelectionEnd(text); |
| 271 | |
| 272 | if (start != end) { |
| 273 | int min = Math.min(start, end); |
| 274 | int max = Math.max(start, end); |
| 275 | |
| 276 | setSelection(text, max); |
| 277 | |
| 278 | if (min == 0 && max == text.length()) { |
| 279 | return false; |
| 280 | } |
| 281 | |
| 282 | return true; |
| 283 | } else { |
| 284 | int line = layout.getLineForOffset(end); |
| 285 | |
| 286 | if (line < layout.getLineCount() - 1) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 287 | setSelectionAndMemory( |
| 288 | text, layout, line, end, 1 /* direction */, false /* extend */); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 289 | return true; |
Raph Levien | fb0431b | 2014-09-04 15:03:14 -0700 | [diff] [blame] | 290 | } else if (end != text.length()) { |
| 291 | setSelection(text, text.length()); |
| 292 | return true; |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 293 | } |
| 294 | } |
| 295 | |
| 296 | return false; |
| 297 | } |
| 298 | |
| 299 | /** |
| 300 | * Move the cursor to the buffer offset physically to the left of |
| 301 | * the current offset, or return false if the cursor is already |
| 302 | * at the left edge of the line and there is not another line to move it to. |
| 303 | */ |
| 304 | public static boolean moveLeft(Spannable text, Layout layout) { |
| 305 | int start = getSelectionStart(text); |
| 306 | int end = getSelectionEnd(text); |
| 307 | |
| 308 | if (start != end) { |
| 309 | setSelection(text, chooseHorizontal(layout, -1, start, end)); |
| 310 | return true; |
| 311 | } else { |
| 312 | int to = layout.getOffsetToLeftOf(end); |
| 313 | |
| 314 | if (to != end) { |
| 315 | setSelection(text, to); |
| 316 | return true; |
| 317 | } |
| 318 | } |
| 319 | |
| 320 | return false; |
| 321 | } |
| 322 | |
| 323 | /** |
| 324 | * Move the cursor to the buffer offset physically to the right of |
| 325 | * the current offset, or return false if the cursor is already at |
| 326 | * at the right edge of the line and there is not another line |
| 327 | * to move it to. |
| 328 | */ |
| 329 | public static boolean moveRight(Spannable text, Layout layout) { |
| 330 | int start = getSelectionStart(text); |
| 331 | int end = getSelectionEnd(text); |
| 332 | |
| 333 | if (start != end) { |
| 334 | setSelection(text, chooseHorizontal(layout, 1, start, end)); |
| 335 | return true; |
| 336 | } else { |
| 337 | int to = layout.getOffsetToRightOf(end); |
| 338 | |
| 339 | if (to != end) { |
| 340 | setSelection(text, to); |
| 341 | return true; |
| 342 | } |
| 343 | } |
| 344 | |
| 345 | return false; |
| 346 | } |
| 347 | |
| 348 | /** |
| 349 | * Move the selection end to the buffer offset physically above |
| 350 | * the current selection end. |
| 351 | */ |
| 352 | public static boolean extendUp(Spannable text, Layout layout) { |
| 353 | int end = getSelectionEnd(text); |
| 354 | int line = layout.getLineForOffset(end); |
| 355 | |
| 356 | if (line > 0) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 357 | setSelectionAndMemory(text, layout, line, end, -1 /* direction */, true /* extend */); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 358 | return true; |
| 359 | } else if (end != 0) { |
| 360 | extendSelection(text, 0); |
| 361 | return true; |
| 362 | } |
| 363 | |
| 364 | return true; |
| 365 | } |
| 366 | |
| 367 | /** |
| 368 | * Move the selection end to the buffer offset physically below |
| 369 | * the current selection end. |
| 370 | */ |
| 371 | public static boolean extendDown(Spannable text, Layout layout) { |
| 372 | int end = getSelectionEnd(text); |
| 373 | int line = layout.getLineForOffset(end); |
| 374 | |
| 375 | if (line < layout.getLineCount() - 1) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 376 | setSelectionAndMemory(text, layout, line, end, 1 /* direction */, true /* extend */); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 377 | return true; |
| 378 | } else if (end != text.length()) { |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 379 | extendSelection(text, text.length(), -1); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 380 | return true; |
| 381 | } |
| 382 | |
| 383 | return true; |
| 384 | } |
| 385 | |
| 386 | /** |
| 387 | * Move the selection end to the buffer offset physically to the left of |
| 388 | * the current selection end. |
| 389 | */ |
| 390 | public static boolean extendLeft(Spannable text, Layout layout) { |
| 391 | int end = getSelectionEnd(text); |
| 392 | int to = layout.getOffsetToLeftOf(end); |
| 393 | |
| 394 | if (to != end) { |
| 395 | extendSelection(text, to); |
| 396 | return true; |
| 397 | } |
| 398 | |
| 399 | return true; |
| 400 | } |
| 401 | |
| 402 | /** |
| 403 | * Move the selection end to the buffer offset physically to the right of |
| 404 | * the current selection end. |
| 405 | */ |
| 406 | public static boolean extendRight(Spannable text, Layout layout) { |
| 407 | int end = getSelectionEnd(text); |
| 408 | int to = layout.getOffsetToRightOf(end); |
| 409 | |
| 410 | if (to != end) { |
| 411 | extendSelection(text, to); |
| 412 | return true; |
| 413 | } |
| 414 | |
| 415 | return true; |
| 416 | } |
| 417 | |
| 418 | public static boolean extendToLeftEdge(Spannable text, Layout layout) { |
| 419 | int where = findEdge(text, layout, -1); |
| 420 | extendSelection(text, where); |
| 421 | return true; |
| 422 | } |
| 423 | |
| 424 | public static boolean extendToRightEdge(Spannable text, Layout layout) { |
| 425 | int where = findEdge(text, layout, 1); |
| 426 | extendSelection(text, where); |
| 427 | return true; |
| 428 | } |
| 429 | |
| 430 | public static boolean moveToLeftEdge(Spannable text, Layout layout) { |
| 431 | int where = findEdge(text, layout, -1); |
| 432 | setSelection(text, where); |
| 433 | return true; |
| 434 | } |
| 435 | |
| 436 | public static boolean moveToRightEdge(Spannable text, Layout layout) { |
| 437 | int where = findEdge(text, layout, 1); |
| 438 | setSelection(text, where); |
| 439 | return true; |
| 440 | } |
| 441 | |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 442 | /** {@hide} */ |
| 443 | public static interface PositionIterator { |
| 444 | public static final int DONE = BreakIterator.DONE; |
| 445 | |
| 446 | public int preceding(int position); |
| 447 | public int following(int position); |
| 448 | } |
| 449 | |
| 450 | /** {@hide} */ |
| 451 | public static boolean moveToPreceding( |
| 452 | Spannable text, PositionIterator iter, boolean extendSelection) { |
| 453 | final int offset = iter.preceding(getSelectionEnd(text)); |
| 454 | if (offset != PositionIterator.DONE) { |
| 455 | if (extendSelection) { |
| 456 | extendSelection(text, offset); |
| 457 | } else { |
| 458 | setSelection(text, offset); |
| 459 | } |
| 460 | } |
| 461 | return true; |
| 462 | } |
| 463 | |
| 464 | /** {@hide} */ |
| 465 | public static boolean moveToFollowing( |
| 466 | Spannable text, PositionIterator iter, boolean extendSelection) { |
| 467 | final int offset = iter.following(getSelectionEnd(text)); |
| 468 | if (offset != PositionIterator.DONE) { |
| 469 | if (extendSelection) { |
| 470 | extendSelection(text, offset); |
| 471 | } else { |
| 472 | setSelection(text, offset); |
| 473 | } |
| 474 | } |
| 475 | return true; |
| 476 | } |
| 477 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 478 | private static int findEdge(Spannable text, Layout layout, int dir) { |
| 479 | int pt = getSelectionEnd(text); |
| 480 | int line = layout.getLineForOffset(pt); |
| 481 | int pdir = layout.getParagraphDirection(line); |
| 482 | |
| 483 | if (dir * pdir < 0) { |
| 484 | return layout.getLineStart(line); |
| 485 | } else { |
| 486 | int end = layout.getLineEnd(line); |
| 487 | |
| 488 | if (line == layout.getLineCount() - 1) |
| 489 | return end; |
| 490 | else |
| 491 | return end - 1; |
| 492 | } |
| 493 | } |
| 494 | |
| 495 | private static int chooseHorizontal(Layout layout, int direction, |
| 496 | int off1, int off2) { |
| 497 | int line1 = layout.getLineForOffset(off1); |
| 498 | int line2 = layout.getLineForOffset(off2); |
| 499 | |
| 500 | if (line1 == line2) { |
| 501 | // same line, so it goes by pure physical direction |
| 502 | |
| 503 | float h1 = layout.getPrimaryHorizontal(off1); |
| 504 | float h2 = layout.getPrimaryHorizontal(off2); |
| 505 | |
| 506 | if (direction < 0) { |
| 507 | // to left |
| 508 | |
| 509 | if (h1 < h2) |
| 510 | return off1; |
| 511 | else |
| 512 | return off2; |
| 513 | } else { |
| 514 | // to right |
| 515 | |
| 516 | if (h1 > h2) |
| 517 | return off1; |
| 518 | else |
| 519 | return off2; |
| 520 | } |
| 521 | } else { |
| 522 | // different line, so which line is "left" and which is "right" |
| 523 | // depends upon the directionality of the text |
| 524 | |
| 525 | // This only checks at one end, but it's not clear what the |
| 526 | // right thing to do is if the ends don't agree. Even if it |
| 527 | // is wrong it should still not be too bad. |
| 528 | int line = layout.getLineForOffset(off1); |
| 529 | int textdir = layout.getParagraphDirection(line); |
| 530 | |
| 531 | if (textdir == direction) |
| 532 | return Math.max(off1, off2); |
| 533 | else |
| 534 | return Math.min(off1, off2); |
| 535 | } |
| 536 | } |
| 537 | |
Gilles Debunne | 2d0e87b | 2010-07-13 10:14:24 -0700 | [diff] [blame] | 538 | private static final class START implements NoCopySpan { } |
| 539 | private static final class END implements NoCopySpan { } |
Clara Bayarri | 6c66f86 | 2016-05-26 10:58:48 +0100 | [diff] [blame] | 540 | private static final class MEMORY implements NoCopySpan { } |
| 541 | private static final Object SELECTION_MEMORY = new MEMORY(); |
Jeff Sharkey | e982dfc1 | 2011-03-21 16:40:23 -0700 | [diff] [blame] | 542 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 543 | /* |
| 544 | * Public constants |
| 545 | */ |
| 546 | |
| 547 | public static final Object SELECTION_START = new START(); |
| 548 | public static final Object SELECTION_END = new END(); |
| 549 | } |