Jeff Brown | 67b6ab7 | 2010-12-17 18:33:02 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2010 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.method; |
| 18 | |
| 19 | import android.text.Layout; |
| 20 | import android.text.Spannable; |
| 21 | import android.view.KeyEvent; |
| 22 | import android.view.MotionEvent; |
| 23 | import android.widget.TextView; |
| 24 | |
| 25 | /** |
| 26 | * Base classes for movement methods. |
| 27 | */ |
| 28 | public class BaseMovementMethod implements MovementMethod { |
| 29 | @Override |
| 30 | public boolean canSelectArbitrarily() { |
| 31 | return false; |
| 32 | } |
| 33 | |
| 34 | @Override |
| 35 | public void initialize(TextView widget, Spannable text) { |
| 36 | } |
| 37 | |
| 38 | @Override |
| 39 | public boolean onKeyDown(TextView widget, Spannable text, int keyCode, KeyEvent event) { |
| 40 | final int movementMetaState = getMovementMetaState(text, event); |
| 41 | boolean handled = handleMovementKey(widget, text, keyCode, movementMetaState, event); |
| 42 | if (handled) { |
| 43 | MetaKeyKeyListener.adjustMetaAfterKeypress(text); |
| 44 | MetaKeyKeyListener.resetLockedMeta(text); |
| 45 | } |
| 46 | return handled; |
| 47 | } |
| 48 | |
| 49 | @Override |
| 50 | public boolean onKeyOther(TextView widget, Spannable text, KeyEvent event) { |
| 51 | final int movementMetaState = getMovementMetaState(text, event); |
| 52 | final int keyCode = event.getKeyCode(); |
| 53 | if (keyCode != KeyEvent.KEYCODE_UNKNOWN |
| 54 | && event.getAction() == KeyEvent.ACTION_MULTIPLE) { |
| 55 | final int repeat = event.getRepeatCount(); |
| 56 | boolean handled = false; |
| 57 | for (int i = 0; i < repeat; i++) { |
| 58 | if (!handleMovementKey(widget, text, keyCode, movementMetaState, event)) { |
| 59 | break; |
| 60 | } |
| 61 | handled = true; |
| 62 | } |
| 63 | if (handled) { |
| 64 | MetaKeyKeyListener.adjustMetaAfterKeypress(text); |
| 65 | MetaKeyKeyListener.resetLockedMeta(text); |
| 66 | } |
| 67 | return handled; |
| 68 | } |
| 69 | return false; |
| 70 | } |
| 71 | |
| 72 | @Override |
| 73 | public boolean onKeyUp(TextView widget, Spannable text, int keyCode, KeyEvent event) { |
| 74 | return false; |
| 75 | } |
| 76 | |
| 77 | @Override |
| 78 | public void onTakeFocus(TextView widget, Spannable text, int direction) { |
| 79 | } |
| 80 | |
| 81 | @Override |
| 82 | public boolean onTouchEvent(TextView widget, Spannable text, MotionEvent event) { |
| 83 | return false; |
| 84 | } |
| 85 | |
| 86 | @Override |
| 87 | public boolean onTrackballEvent(TextView widget, Spannable text, MotionEvent event) { |
| 88 | return false; |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Gets the meta state used for movement using the modifiers tracked by the text |
| 93 | * buffer as well as those present in the key event. |
| 94 | * |
| 95 | * The movement meta state excludes the state of locked modifiers or the SHIFT key |
| 96 | * since they are not used by movement actions (but they may be used for selection). |
| 97 | * |
| 98 | * @param buffer The text buffer. |
| 99 | * @param event The key event. |
| 100 | * @return The keyboard meta states used for movement. |
| 101 | */ |
| 102 | protected int getMovementMetaState(Spannable buffer, KeyEvent event) { |
| 103 | // We ignore locked modifiers and SHIFT. |
| 104 | int metaState = (event.getMetaState() | MetaKeyKeyListener.getMetaState(buffer)) |
| 105 | & ~(MetaKeyKeyListener.META_ALT_LOCKED | MetaKeyKeyListener.META_SYM_LOCKED); |
| 106 | return KeyEvent.normalizeMetaState(metaState) & ~KeyEvent.META_SHIFT_MASK; |
| 107 | } |
| 108 | |
| 109 | /** |
| 110 | * Performs a movement key action. |
| 111 | * The default implementation decodes the key down and invokes movement actions |
| 112 | * such as {@link #down} and {@link #up}. |
| 113 | * {@link #onKeyDown(TextView, Spannable, int, KeyEvent)} calls this method once |
| 114 | * to handle an {@link KeyEvent#ACTION_DOWN}. |
| 115 | * {@link #onKeyOther(TextView, Spannable, KeyEvent)} calls this method repeatedly |
| 116 | * to handle each repetition of an {@link KeyEvent#ACTION_MULTIPLE}. |
| 117 | * |
| 118 | * @param widget The text view. |
| 119 | * @param buffer The text buffer. |
| 120 | * @param event The key event. |
| 121 | * @param keyCode The key code. |
| 122 | * @param movementMetaState The keyboard meta states used for movement. |
| 123 | * @param event The key event. |
| 124 | * @return True if the event was handled. |
| 125 | */ |
| 126 | protected boolean handleMovementKey(TextView widget, Spannable buffer, |
| 127 | int keyCode, int movementMetaState, KeyEvent event) { |
| 128 | switch (keyCode) { |
| 129 | case KeyEvent.KEYCODE_DPAD_LEFT: |
| 130 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 131 | return left(widget, buffer); |
| 132 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 133 | KeyEvent.META_ALT_ON)) { |
| 134 | return lineStart(widget, buffer); |
| 135 | } |
| 136 | break; |
| 137 | |
| 138 | case KeyEvent.KEYCODE_DPAD_RIGHT: |
| 139 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 140 | return right(widget, buffer); |
| 141 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 142 | KeyEvent.META_ALT_ON)) { |
| 143 | return lineEnd(widget, buffer); |
| 144 | } |
| 145 | break; |
| 146 | |
| 147 | case KeyEvent.KEYCODE_DPAD_UP: |
| 148 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 149 | return up(widget, buffer); |
| 150 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 151 | KeyEvent.META_ALT_ON)) { |
| 152 | return top(widget, buffer); |
| 153 | } |
| 154 | break; |
| 155 | |
| 156 | case KeyEvent.KEYCODE_DPAD_DOWN: |
| 157 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 158 | return down(widget, buffer); |
| 159 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 160 | KeyEvent.META_ALT_ON)) { |
| 161 | return bottom(widget, buffer); |
| 162 | } |
| 163 | break; |
| 164 | |
| 165 | case KeyEvent.KEYCODE_PAGE_UP: |
| 166 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 167 | return pageUp(widget, buffer); |
| 168 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 169 | KeyEvent.META_ALT_ON)) { |
| 170 | return top(widget, buffer); |
| 171 | } |
| 172 | break; |
| 173 | |
| 174 | case KeyEvent.KEYCODE_PAGE_DOWN: |
| 175 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 176 | return pageDown(widget, buffer); |
| 177 | } else if (KeyEvent.metaStateHasModifiers(movementMetaState, |
| 178 | KeyEvent.META_ALT_ON)) { |
| 179 | return bottom(widget, buffer); |
| 180 | } |
| 181 | break; |
| 182 | |
| 183 | case KeyEvent.KEYCODE_MOVE_HOME: |
| 184 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 185 | return home(widget, buffer); |
| 186 | } |
| 187 | break; |
| 188 | |
| 189 | case KeyEvent.KEYCODE_MOVE_END: |
| 190 | if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| 191 | return end(widget, buffer); |
| 192 | } |
| 193 | break; |
| 194 | } |
| 195 | return false; |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * Performs a left movement action. |
| 200 | * Moves the cursor or scrolls left by one character. |
| 201 | * |
| 202 | * @param widget The text view. |
| 203 | * @param buffer The text buffer. |
| 204 | * @return True if the event was handled. |
| 205 | */ |
| 206 | protected boolean left(TextView widget, Spannable buffer) { |
| 207 | return false; |
| 208 | } |
| 209 | |
| 210 | /** |
| 211 | * Performs a right movement action. |
| 212 | * Moves the cursor or scrolls right by one character. |
| 213 | * |
| 214 | * @param widget The text view. |
| 215 | * @param buffer The text buffer. |
| 216 | * @return True if the event was handled. |
| 217 | */ |
| 218 | protected boolean right(TextView widget, Spannable buffer) { |
| 219 | return false; |
| 220 | } |
| 221 | |
| 222 | /** |
| 223 | * Performs an up movement action. |
| 224 | * Moves the cursor or scrolls up by one line. |
| 225 | * |
| 226 | * @param widget The text view. |
| 227 | * @param buffer The text buffer. |
| 228 | * @return True if the event was handled. |
| 229 | */ |
| 230 | protected boolean up(TextView widget, Spannable buffer) { |
| 231 | return false; |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * Performs a down movement action. |
| 236 | * Moves the cursor or scrolls down by one line. |
| 237 | * |
| 238 | * @param widget The text view. |
| 239 | * @param buffer The text buffer. |
| 240 | * @return True if the event was handled. |
| 241 | */ |
| 242 | protected boolean down(TextView widget, Spannable buffer) { |
| 243 | return false; |
| 244 | } |
| 245 | |
| 246 | /** |
| 247 | * Performs a page-up movement action. |
| 248 | * Moves the cursor or scrolls up by one page. |
| 249 | * |
| 250 | * @param widget The text view. |
| 251 | * @param buffer The text buffer. |
| 252 | * @return True if the event was handled. |
| 253 | */ |
| 254 | protected boolean pageUp(TextView widget, Spannable buffer) { |
| 255 | return false; |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * Performs a page-down movement action. |
| 260 | * Moves the cursor or scrolls down by one page. |
| 261 | * |
| 262 | * @param widget The text view. |
| 263 | * @param buffer The text buffer. |
| 264 | * @return True if the event was handled. |
| 265 | */ |
| 266 | protected boolean pageDown(TextView widget, Spannable buffer) { |
| 267 | return false; |
| 268 | } |
| 269 | |
| 270 | /** |
| 271 | * Performs a top movement action. |
| 272 | * Moves the cursor or scrolls to the top of the buffer. |
| 273 | * |
| 274 | * @param widget The text view. |
| 275 | * @param buffer The text buffer. |
| 276 | * @return True if the event was handled. |
| 277 | */ |
| 278 | protected boolean top(TextView widget, Spannable buffer) { |
| 279 | return false; |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * Performs a bottom movement action. |
| 284 | * Moves the cursor or scrolls to the bottom of the buffer. |
| 285 | * |
| 286 | * @param widget The text view. |
| 287 | * @param buffer The text buffer. |
| 288 | * @return True if the event was handled. |
| 289 | */ |
| 290 | protected boolean bottom(TextView widget, Spannable buffer) { |
| 291 | return false; |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * Performs a line-start movement action. |
| 296 | * Moves the cursor or scrolls to the start of the line. |
| 297 | * |
| 298 | * @param widget The text view. |
| 299 | * @param buffer The text buffer. |
| 300 | * @return True if the event was handled. |
| 301 | */ |
| 302 | protected boolean lineStart(TextView widget, Spannable buffer) { |
| 303 | return false; |
| 304 | } |
| 305 | |
| 306 | /** |
| 307 | * Performs an line-end movement action. |
| 308 | * Moves the cursor or scrolls to the end of the line. |
| 309 | * |
| 310 | * @param widget The text view. |
| 311 | * @param buffer The text buffer. |
| 312 | * @return True if the event was handled. |
| 313 | */ |
| 314 | protected boolean lineEnd(TextView widget, Spannable buffer) { |
| 315 | return false; |
| 316 | } |
| 317 | |
| 318 | /** |
| 319 | * Performs a home movement action. |
| 320 | * Moves the cursor or scrolls to the start of the line or to the top of the |
| 321 | * document depending on whether the insertion point is being moved or |
| 322 | * the document is being scrolled. |
| 323 | * |
| 324 | * @param widget The text view. |
| 325 | * @param buffer The text buffer. |
| 326 | * @return True if the event was handled. |
| 327 | */ |
| 328 | protected boolean home(TextView widget, Spannable buffer) { |
| 329 | return false; |
| 330 | } |
| 331 | |
| 332 | /** |
| 333 | * Performs an end movement action. |
| 334 | * Moves the cursor or scrolls to the start of the line or to the top of the |
| 335 | * document depending on whether the insertion point is being moved or |
| 336 | * the document is being scrolled. |
| 337 | * |
| 338 | * @param widget The text view. |
| 339 | * @param buffer The text buffer. |
| 340 | * @return True if the event was handled. |
| 341 | */ |
| 342 | protected boolean end(TextView widget, Spannable buffer) { |
| 343 | return false; |
| 344 | } |
| 345 | } |