| 1 | /* |
| 2 | * Jexer - Java Text User Interface |
| 3 | * |
| 4 | * License: LGPLv3 or later |
| 5 | * |
| 6 | * This module is licensed under the GNU Lesser General Public License |
| 7 | * Version 3. Please see the file "COPYING" in this directory for more |
| 8 | * information about the GNU Lesser General Public License Version 3. |
| 9 | * |
| 10 | * Copyright (C) 2015 Kevin Lamonte |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU Lesser General Public License |
| 14 | * as published by the Free Software Foundation; either version 3 of |
| 15 | * the License, or (at your option) any later version. |
| 16 | * |
| 17 | * This program is distributed in the hope that it will be useful, but |
| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 20 | * General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Lesser General Public |
| 23 | * License along with this program; if not, see |
| 24 | * http://www.gnu.org/licenses/, or write to the Free Software |
| 25 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| 26 | * 02110-1301 USA |
| 27 | * |
| 28 | * @author Kevin Lamonte [kevin.lamonte@gmail.com] |
| 29 | * @version 1 |
| 30 | */ |
| 31 | package jexer; |
| 32 | |
| 33 | import jexer.event.TKeypressEvent; |
| 34 | import jexer.event.TMouseEvent; |
| 35 | import static jexer.TKeypress.*; |
| 36 | |
| 37 | /** |
| 38 | * TTreeView implements a simple tree view. |
| 39 | */ |
| 40 | public class TTreeView extends TWidget { |
| 41 | |
| 42 | /** |
| 43 | * Vertical scrollbar. |
| 44 | */ |
| 45 | private TVScroller vScroller; |
| 46 | |
| 47 | /** |
| 48 | * Horizontal scrollbar. |
| 49 | */ |
| 50 | private THScroller hScroller; |
| 51 | |
| 52 | /** |
| 53 | * Get the horizontal scrollbar. This is used by TTreeItem.draw(), and |
| 54 | * potentially subclasses. |
| 55 | * |
| 56 | * @return the horizontal scrollbar |
| 57 | */ |
| 58 | public final THScroller getHScroller() { |
| 59 | return hScroller; |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Root of the tree. |
| 64 | */ |
| 65 | private TTreeItem treeRoot; |
| 66 | |
| 67 | /** |
| 68 | * Get the root of the tree. |
| 69 | * |
| 70 | * @return the root of the tree |
| 71 | */ |
| 72 | public final TTreeItem getTreeRoot() { |
| 73 | return treeRoot; |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Set the root of the tree. |
| 78 | * |
| 79 | * @param treeRoot the new root of the tree |
| 80 | */ |
| 81 | public final void setTreeRoot(final TTreeItem treeRoot) { |
| 82 | this.treeRoot = treeRoot; |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Maximum width of a single line. |
| 87 | */ |
| 88 | private int maxLineWidth; |
| 89 | |
| 90 | /** |
| 91 | * Only one of my children can be selected. |
| 92 | */ |
| 93 | private TTreeItem selectedItem = null; |
| 94 | |
| 95 | /** |
| 96 | * If true, move the window to put the selected item in view. This |
| 97 | * normally only happens once after setting treeRoot. |
| 98 | */ |
| 99 | private boolean centerWindow = false; |
| 100 | |
| 101 | /** |
| 102 | * The action to perform when the user selects an item. |
| 103 | */ |
| 104 | private TAction action = null; |
| 105 | |
| 106 | /** |
| 107 | * Set treeRoot. |
| 108 | * |
| 109 | * @param treeRoot ultimate root of tree |
| 110 | * @param centerWindow if true, move the window to put the root in view |
| 111 | */ |
| 112 | public void setTreeRoot(final TTreeItem treeRoot, |
| 113 | final boolean centerWindow) { |
| 114 | |
| 115 | this.treeRoot = treeRoot; |
| 116 | this.centerWindow = centerWindow; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Public constructor. |
| 121 | * |
| 122 | * @param parent parent widget |
| 123 | * @param x column relative to parent |
| 124 | * @param y row relative to parent |
| 125 | * @param width width of tree view |
| 126 | * @param height height of tree view |
| 127 | */ |
| 128 | public TTreeView(final TWidget parent, final int x, final int y, |
| 129 | final int width, final int height) { |
| 130 | |
| 131 | this(parent, x, y, width, height, null); |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * Public constructor. |
| 136 | * |
| 137 | * @param parent parent widget |
| 138 | * @param x column relative to parent |
| 139 | * @param y row relative to parent |
| 140 | * @param width width of tree view |
| 141 | * @param height height of tree view |
| 142 | * @param action action to perform when an item is selected |
| 143 | */ |
| 144 | public TTreeView(final TWidget parent, final int x, final int y, |
| 145 | final int width, final int height, final TAction action) { |
| 146 | |
| 147 | super(parent, x, y, width, height); |
| 148 | this.action = action; |
| 149 | } |
| 150 | |
| 151 | /** |
| 152 | * Get the tree view item that was selected. |
| 153 | * |
| 154 | * @return the selected item, or null if no item is selected |
| 155 | */ |
| 156 | public final TTreeItem getSelected() { |
| 157 | return selectedItem; |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Set the new selected tree view item. |
| 162 | * |
| 163 | * @param item new item that became selected |
| 164 | */ |
| 165 | public void setSelected(final TTreeItem item) { |
| 166 | if (item != null) { |
| 167 | item.setSelected(true); |
| 168 | } |
| 169 | if ((selectedItem != null) && (selectedItem != item)) { |
| 170 | selectedItem.setSelected(false); |
| 171 | } |
| 172 | selectedItem = item; |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * Perform user selection action. |
| 177 | */ |
| 178 | public void dispatch() { |
| 179 | if (action != null) { |
| 180 | action.DO(); |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | /** |
| 185 | * Update (or instantiate) vScroller and hScroller. |
| 186 | */ |
| 187 | private void updateScrollers() { |
| 188 | // Setup vertical scroller |
| 189 | if (vScroller == null) { |
| 190 | vScroller = new TVScroller(this, getWidth() - 1, 0, |
| 191 | getHeight() - 1); |
| 192 | vScroller.setValue(0); |
| 193 | vScroller.setTopValue(0); |
| 194 | } |
| 195 | vScroller.setX(getWidth() - 1); |
| 196 | vScroller.setHeight(getHeight() - 1); |
| 197 | vScroller.setBigChange(getHeight() - 1); |
| 198 | |
| 199 | // Setup horizontal scroller |
| 200 | if (hScroller == null) { |
| 201 | hScroller = new THScroller(this, 0, getHeight() - 1, |
| 202 | getWidth() - 1); |
| 203 | hScroller.setValue(0); |
| 204 | hScroller.setLeftValue(0); |
| 205 | } |
| 206 | hScroller.setY(getHeight() - 1); |
| 207 | hScroller.setWidth(getWidth() - 1); |
| 208 | hScroller.setBigChange(getWidth() - 1); |
| 209 | } |
| 210 | |
| 211 | /** |
| 212 | * Resize text and scrollbars for a new width/height. |
| 213 | */ |
| 214 | public void reflow() { |
| 215 | int selectedRow = 0; |
| 216 | boolean foundSelectedRow = false; |
| 217 | |
| 218 | updateScrollers(); |
| 219 | if (treeRoot == null) { |
| 220 | return; |
| 221 | } |
| 222 | |
| 223 | // Make each child invisible/inactive to start, expandTree() will |
| 224 | // reactivate the visible ones. |
| 225 | for (TWidget widget: getChildren()) { |
| 226 | if (widget instanceof TTreeItem) { |
| 227 | TTreeItem item = (TTreeItem) widget; |
| 228 | item.setInvisible(true); |
| 229 | item.setEnabled(false); |
| 230 | item.keyboardPrevious = null; |
| 231 | item.keyboardNext = null; |
| 232 | } |
| 233 | } |
| 234 | |
| 235 | // Expand the tree into a linear list |
| 236 | getChildren().clear(); |
| 237 | getChildren().addAll(treeRoot.expandTree("", true)); |
| 238 | |
| 239 | // Locate the selected row and maximum line width |
| 240 | for (TWidget widget: getChildren()) { |
| 241 | TTreeItem item = (TTreeItem) widget; |
| 242 | |
| 243 | if (item == selectedItem) { |
| 244 | foundSelectedRow = true; |
| 245 | } |
| 246 | if (!foundSelectedRow) { |
| 247 | selectedRow++; |
| 248 | } |
| 249 | |
| 250 | int lineWidth = item.getText().length() |
| 251 | + item.getPrefix().length() + 4; |
| 252 | if (lineWidth > maxLineWidth) { |
| 253 | maxLineWidth = lineWidth; |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | if ((centerWindow) && (foundSelectedRow)) { |
| 258 | if ((selectedRow < vScroller.getValue()) |
| 259 | || (selectedRow > vScroller.getValue() + getHeight() - 2) |
| 260 | ) { |
| 261 | vScroller.setValue(selectedRow); |
| 262 | centerWindow = false; |
| 263 | } |
| 264 | } |
| 265 | updatePositions(); |
| 266 | |
| 267 | // Rescale the scroll bars |
| 268 | vScroller.setBottomValue(getChildren().size() - getHeight() + 1); |
| 269 | if (vScroller.getBottomValue() < 0) { |
| 270 | vScroller.setBottomValue(0); |
| 271 | } |
| 272 | /* |
| 273 | if (vScroller.getValue() > vScroller.getBottomValue()) { |
| 274 | vScroller.setValue(vScroller.getBottomValue()); |
| 275 | } |
| 276 | */ |
| 277 | hScroller.setRightValue(maxLineWidth - getWidth() + 3); |
| 278 | if (hScroller.getRightValue() < 0) { |
| 279 | hScroller.setRightValue(0); |
| 280 | } |
| 281 | /* |
| 282 | if (hScroller.getValue() > hScroller.getRightValue()) { |
| 283 | hScroller.setValue(hScroller.getRightValue()); |
| 284 | } |
| 285 | */ |
| 286 | getChildren().add(hScroller); |
| 287 | getChildren().add(vScroller); |
| 288 | } |
| 289 | |
| 290 | /** |
| 291 | * Update the Y positions of all the children items. |
| 292 | */ |
| 293 | private void updatePositions() { |
| 294 | if (treeRoot == null) { |
| 295 | return; |
| 296 | } |
| 297 | |
| 298 | int begin = vScroller.getValue(); |
| 299 | int topY = 0; |
| 300 | |
| 301 | // As we walk the list we also adjust next/previous pointers, |
| 302 | // resulting in a doubly-linked list but only of the expanded items. |
| 303 | TTreeItem p = null; |
| 304 | |
| 305 | for (int i = 0; i < getChildren().size(); i++) { |
| 306 | if (!(getChildren().get(i) instanceof TTreeItem)) { |
| 307 | // Skip the scrollbars |
| 308 | continue; |
| 309 | } |
| 310 | TTreeItem item = (TTreeItem) getChildren().get(i); |
| 311 | |
| 312 | if (p != null) { |
| 313 | item.keyboardPrevious = p; |
| 314 | p.keyboardNext = item; |
| 315 | } |
| 316 | p = item; |
| 317 | |
| 318 | if (i < begin) { |
| 319 | // Render invisible |
| 320 | item.setEnabled(false); |
| 321 | item.setInvisible(true); |
| 322 | continue; |
| 323 | } |
| 324 | |
| 325 | if (topY >= getHeight() - 1) { |
| 326 | // Render invisible |
| 327 | item.setEnabled(false); |
| 328 | item.setInvisible(true); |
| 329 | continue; |
| 330 | } |
| 331 | |
| 332 | item.setY(topY); |
| 333 | item.setEnabled(true); |
| 334 | item.setInvisible(false); |
| 335 | item.setWidth(getWidth() - 1); |
| 336 | topY++; |
| 337 | } |
| 338 | |
| 339 | } |
| 340 | |
| 341 | /** |
| 342 | * Handle mouse press events. |
| 343 | * |
| 344 | * @param mouse mouse button press event |
| 345 | */ |
| 346 | @Override |
| 347 | public void onMouseDown(final TMouseEvent mouse) { |
| 348 | if (mouse.isMouseWheelUp()) { |
| 349 | vScroller.decrement(); |
| 350 | } else if (mouse.isMouseWheelDown()) { |
| 351 | vScroller.increment(); |
| 352 | } else { |
| 353 | // Pass to children |
| 354 | super.onMouseDown(mouse); |
| 355 | } |
| 356 | |
| 357 | // Update the screen after the scrollbars have moved |
| 358 | reflow(); |
| 359 | } |
| 360 | |
| 361 | /** |
| 362 | * Handle mouse release events. |
| 363 | * |
| 364 | * @param mouse mouse button release event |
| 365 | */ |
| 366 | @Override |
| 367 | public void onMouseUp(final TMouseEvent mouse) { |
| 368 | // Pass to children |
| 369 | super.onMouseDown(mouse); |
| 370 | |
| 371 | // Update the screen after any thing has expanded/contracted |
| 372 | reflow(); |
| 373 | } |
| 374 | |
| 375 | /** |
| 376 | * Handle keystrokes. |
| 377 | * |
| 378 | * @param keypress keystroke event |
| 379 | */ |
| 380 | @Override |
| 381 | public void onKeypress(final TKeypressEvent keypress) { |
| 382 | if (keypress.equals(kbShiftLeft) |
| 383 | || keypress.equals(kbCtrlLeft) |
| 384 | || keypress.equals(kbAltLeft) |
| 385 | ) { |
| 386 | hScroller.decrement(); |
| 387 | } else if (keypress.equals(kbShiftRight) |
| 388 | || keypress.equals(kbCtrlRight) |
| 389 | || keypress.equals(kbAltRight) |
| 390 | ) { |
| 391 | hScroller.increment(); |
| 392 | } else if (keypress.equals(kbShiftUp) |
| 393 | || keypress.equals(kbCtrlUp) |
| 394 | || keypress.equals(kbAltUp) |
| 395 | ) { |
| 396 | vScroller.decrement(); |
| 397 | } else if (keypress.equals(kbShiftDown) |
| 398 | || keypress.equals(kbCtrlDown) |
| 399 | || keypress.equals(kbAltDown) |
| 400 | ) { |
| 401 | vScroller.increment(); |
| 402 | } else if (keypress.equals(kbShiftPgUp) |
| 403 | || keypress.equals(kbCtrlPgUp) |
| 404 | || keypress.equals(kbAltPgUp) |
| 405 | ) { |
| 406 | vScroller.bigDecrement(); |
| 407 | } else if (keypress.equals(kbShiftPgDn) |
| 408 | || keypress.equals(kbCtrlPgDn) |
| 409 | || keypress.equals(kbAltPgDn) |
| 410 | ) { |
| 411 | vScroller.bigIncrement(); |
| 412 | } else if (keypress.equals(kbHome)) { |
| 413 | vScroller.toTop(); |
| 414 | } else if (keypress.equals(kbEnd)) { |
| 415 | vScroller.toBottom(); |
| 416 | } else if (keypress.equals(kbEnter)) { |
| 417 | if (selectedItem != null) { |
| 418 | dispatch(); |
| 419 | } |
| 420 | } else if (keypress.equals(kbUp)) { |
| 421 | // Select the previous item |
| 422 | if (selectedItem != null) { |
| 423 | TTreeItem oldItem = selectedItem; |
| 424 | if (selectedItem.keyboardPrevious != null) { |
| 425 | setSelected(selectedItem.keyboardPrevious); |
| 426 | if (oldItem.getY() == 0) { |
| 427 | vScroller.decrement(); |
| 428 | } |
| 429 | } |
| 430 | } |
| 431 | } else if (keypress.equals(kbDown)) { |
| 432 | // Select the next item |
| 433 | if (selectedItem != null) { |
| 434 | TTreeItem oldItem = selectedItem; |
| 435 | if (selectedItem.keyboardNext != null) { |
| 436 | setSelected(selectedItem.keyboardNext); |
| 437 | if (oldItem.getY() == getHeight() - 2) { |
| 438 | vScroller.increment(); |
| 439 | } |
| 440 | } |
| 441 | } |
| 442 | } else if (keypress.equals(kbTab)) { |
| 443 | getParent().switchWidget(true); |
| 444 | return; |
| 445 | } else if (keypress.equals(kbShiftTab) |
| 446 | || keypress.equals(kbBackTab)) { |
| 447 | getParent().switchWidget(false); |
| 448 | return; |
| 449 | } else if (selectedItem != null) { |
| 450 | // Give the TTreeItem a chance to handle arrow keys |
| 451 | selectedItem.onKeypress(keypress); |
| 452 | } else { |
| 453 | // Pass other keys (tab etc.) on to TWidget's handler. |
| 454 | super.onKeypress(keypress); |
| 455 | return; |
| 456 | } |
| 457 | |
| 458 | // Update the screen after any thing has expanded/contracted |
| 459 | reflow(); |
| 460 | } |
| 461 | |
| 462 | } |