src/jexer/TSplitPane.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2019 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer;
  30
  31 import jexer.bits.CellAttributes;
  32 import jexer.bits.GraphicsChars;
  33 import jexer.event.TMenuEvent;
  34 import jexer.event.TMouseEvent;
  35 import jexer.event.TResizeEvent;
  36 import jexer.menu.TMenu;
  37
  38 /**
  39  * TSplitPane contains two widgets with a draggable horizontal or vertical
  40  * bar between them.
  41  */
  42 public class TSplitPane extends TWidget {
  43
  44     // ------------------------------------------------------------------------
  45     // Variables --------------------------------------------------------------
  46     // ------------------------------------------------------------------------
  47
  48     /**
  49      * If true, split vertically.  If false, split horizontally.
  50      */
  51     private boolean vertical = true;
  52
  53     /**
  54      * The location of the split bar, either as a column number for vertical
  55      * split or a row number for horizontal split.
  56      */
  57     private int split = 0;
  58
  59     /**
  60      * The widget on the left side.
  61      */
  62     private TWidget left;
  63
  64     /**
  65      * The widget on the right side.
  66      */
  67     private TWidget right;
  68
  69     /**
  70      * The widget on the top side.
  71      */
  72     private TWidget top;
  73
  74     /**
  75      * The widget on the bottom side.
  76      */
  77     private TWidget bottom;
  78
  79     /**
  80      * If true, we are in the middle of a split move.
  81      */
  82     private boolean inSplitMove = false;
  83
  84     /**
  85      * The last seen mouse position.
  86      */
  87     private TMouseEvent mouse;
  88
  89     // ------------------------------------------------------------------------
  90     // Constructors -----------------------------------------------------------
  91     // ------------------------------------------------------------------------
  92
  93     /**
  94      * Public constructor.
  95      *
  96      * @param parent parent widget
  97      * @param x column relative to parent
  98      * @param y row relative to parent
  99      * @param width width of widget
 100      * @param height height of widget
 101      * @param vertical if true, split vertically
 102      */
 103     public TSplitPane(final TWidget parent, final int x, final int y,
 104         final int width, final int height, final boolean vertical) {
 105
 106         super(parent, x, y, width, height);
 107
 108         this.vertical = vertical;
 109         center();
 110     }
 111
 112     // ------------------------------------------------------------------------
 113     // Event handlers ---------------------------------------------------------
 114     // ------------------------------------------------------------------------
 115
 116     /**
 117      * Handle window/screen resize events.
 118      *
 119      * @param event resize event
 120      */
 121     @Override
 122     public void onResize(final TResizeEvent event) {
 123         if (event.getType() == TResizeEvent.Type.WIDGET) {
 124             // Resize me
 125             super.onResize(event);
 126
 127             if (vertical && (split >= getWidth() - 2)) {
 128                 center();
 129             } else if (!vertical && (split >= getHeight() - 2)) {
 130                 center();
 131             } else {
 132                 layoutChildren();
 133             }
 134         }
 135     }
 136
 137     /**
 138      * Handle mouse button presses.
 139      *
 140      * @param mouse mouse button event
 141      */
 142     @Override
 143     public void onMouseDown(final TMouseEvent mouse) {
 144         this.mouse = mouse;
 145
 146         inSplitMove = false;
 147
 148         if (mouse.isMouse1()) {
 149             if (vertical) {
 150                 inSplitMove = (mouse.getAbsoluteX() - getAbsoluteX() == split);
 151             } else {
 152                 inSplitMove = (mouse.getAbsoluteY() - getAbsoluteY() == split);
 153             }
 154             if (inSplitMove) {
 155                 return;
 156             }
 157         }
 158
 159         // I didn't take it, pass it on to my children
 160         super.onMouseDown(mouse);
 161     }
 162
 163     /**
 164      * Handle mouse button releases.
 165      *
 166      * @param mouse mouse button release event
 167      */
 168     @Override
 169     public void onMouseUp(final TMouseEvent mouse) {
 170         this.mouse = mouse;
 171
 172         if (inSplitMove && mouse.isMouse1()) {
 173             // Stop moving split
 174             inSplitMove = false;
 175             return;
 176         }
 177
 178         // I didn't take it, pass it on to my children
 179         super.onMouseUp(mouse);
 180     }
 181
 182     /**
 183      * Handle mouse movements.
 184      *
 185      * @param mouse mouse motion event
 186      */
 187     @Override
 188     public void onMouseMotion(final TMouseEvent mouse) {
 189         this.mouse = mouse;
 190
 191         if ((mouse.getAbsoluteX() - getAbsoluteX() < 0)
 192             || (mouse.getAbsoluteX() - getAbsoluteX() >= getWidth())
 193             || (mouse.getAbsoluteY() - getAbsoluteY() < 0)
 194             || (mouse.getAbsoluteY() - getAbsoluteY() >= getHeight())
 195         ) {
 196             // Mouse has travelled out of my window.
 197             inSplitMove = false;
 198         }
 199
 200         if (inSplitMove) {
 201             if (vertical) {
 202                 split = mouse.getAbsoluteX() - getAbsoluteX();
 203                 split = Math.min(Math.max(1, split), getWidth() - 2);
 204             } else {
 205                 split = mouse.getAbsoluteY() - getAbsoluteY();
 206                 split = Math.min(Math.max(1, split), getHeight() - 2);
 207             }
 208             layoutChildren();
 209             return;
 210         }
 211
 212         // I didn't take it, pass it on to my children
 213         super.onMouseMotion(mouse);
 214     }
 215
 216     // ------------------------------------------------------------------------
 217     // TWidget ----------------------------------------------------------------
 218     // ------------------------------------------------------------------------
 219
 220     /**
 221      * Draw me on screen.
 222      */
 223     @Override
 224     public void draw() {
 225         CellAttributes attr = getTheme().getColor("tsplitpane");
 226         if (vertical) {
 227             vLineXY(split, 0, getHeight(), GraphicsChars.WINDOW_SIDE, attr);
 228             // TODO: draw intersections of children
 229
 230             if ((mouse != null)
 231                 && (mouse.getAbsoluteX() == getAbsoluteX() + split)
 232                 && (mouse.getAbsoluteY() >= getAbsoluteY()) &&
 233                 (mouse.getAbsoluteY() < getAbsoluteY() + getHeight())
 234             ) {
 235                 putCharXY(split, mouse.getAbsoluteY() - getAbsoluteY(),
 236                     '\u2194', attr);
 237             }
 238         } else {
 239             hLineXY(0, split, getWidth(), GraphicsChars.SINGLE_BAR, attr);
 240             // TODO: draw intersections of children
 241
 242             if ((mouse != null)
 243                 && (mouse.getAbsoluteY() == getAbsoluteY() + split)
 244                 && (mouse.getAbsoluteX() >= getAbsoluteX()) &&
 245                 (mouse.getAbsoluteX() < getAbsoluteX() + getWidth())
 246             ) {
 247                 putCharXY(mouse.getAbsoluteX() - getAbsoluteX(), split,
 248                     '\u2195', attr);
 249             }
 250         }
 251
 252     }
 253
 254     /**
 255      * Generate a human-readable string for this widget.
 256      *
 257      * @return a human-readable string
 258      */
 259     @Override
 260     public String toString() {
 261         return String.format("%s(%8x) %s position (%d, %d) geometry %dx%d " +
 262             "split %d left %s(%8x) right %s(%8x) top %s(%8x) bottom %s(%8x) " +
 263             "active %s enabled %s visible %s", getClass().getName(),
 264             hashCode(), (vertical ? "VERTICAL" : "HORIZONTAL"),
 265             getX(), getY(), getWidth(), getHeight(), split,
 266             (left == null ? "null" : left.getClass().getName()),
 267             (left == null ? 0 : left.hashCode()),
 268             (right == null ? "null" : right.getClass().getName()),
 269             (right == null ? 0 : right.hashCode()),
 270             (top == null ? "null" : top.getClass().getName()),
 271             (top == null ? 0 : top.hashCode()),
 272             (bottom == null ? "null" : bottom.getClass().getName()),
 273             (bottom == null ? 0 : bottom.hashCode()),
 274             isActive(), isEnabled(), isVisible());
 275     }
 276
 277     // ------------------------------------------------------------------------
 278     // TSplitPane -------------------------------------------------------------
 279     // ------------------------------------------------------------------------
 280
 281     /**
 282      * Get the widget on the left side.
 283      *
 284      * @return the widget on the left, or null if not set
 285      */
 286     public TWidget getLeft() {
 287         return left;
 288     }
 289
 290     /**
 291      * Set the widget on the left side.
 292      *
 293      * @param left the widget to set, or null to remove
 294      */
 295     public void setLeft(final TWidget left) {
 296         if (!vertical) {
 297             throw new IllegalArgumentException("cannot set left on " +
 298                 "horizontal split pane");
 299         }
 300         if (left == null) {
 301             if (this.left != null) {
 302                 remove(this.left);
 303             }
 304             this.left = null;
 305             return;
 306         }
 307         this.left = left;
 308         left.setParent(this, false);
 309         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 310                 getHeight()));
 311     }
 312
 313     /**
 314      * Get the widget on the right side.
 315      *
 316      * @return the widget on the right, or null if not set
 317      */
 318     public TWidget getRight() {
 319         return right;
 320     }
 321
 322     /**
 323      * Set the widget on the right side.
 324      *
 325      * @param right the widget to set, or null to remove
 326      */
 327     public void setRight(final TWidget right) {
 328         if (!vertical) {
 329             throw new IllegalArgumentException("cannot set right on " +
 330                 "horizontal split pane");
 331         }
 332         if (right == null) {
 333             if (this.right != null) {
 334                 remove(this.right);
 335             }
 336             this.right = null;
 337             return;
 338         }
 339         this.right = right;
 340         right.setParent(this, false);
 341         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 342                 getHeight()));
 343     }
 344
 345     /**
 346      * Get the widget on the top side.
 347      *
 348      * @return the widget on the top, or null if not set
 349      */
 350     public TWidget getTop() {
 351         return top;
 352     }
 353
 354     /**
 355      * Set the widget on the top side.
 356      *
 357      * @param top the widget to set, or null to remove
 358      */
 359     public void setTop(final TWidget top) {
 360         if (vertical) {
 361             throw new IllegalArgumentException("cannot set top on vertical " +
 362                 "split pane");
 363         }
 364         if (top == null) {
 365             if (this.top != null) {
 366                 remove(this.top);
 367             }
 368             this.top = null;
 369             return;
 370         }
 371         this.top = top;
 372         top.setParent(this, false);
 373         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 374                 getHeight()));
 375     }
 376
 377     /**
 378      * Get the widget on the bottom side.
 379      *
 380      * @return the widget on the bottom, or null if not set
 381      */
 382     public TWidget getBottom() {
 383         return bottom;
 384     }
 385
 386     /**
 387      * Set the widget on the bottom side.
 388      *
 389      * @param bottom the widget to set, or null to remove
 390      */
 391     public void setBottom(final TWidget bottom) {
 392         if (vertical) {
 393             throw new IllegalArgumentException("cannot set bottom on " +
 394                 "vertical split pane");
 395         }
 396         if (bottom == null) {
 397             if (this.bottom != null) {
 398                 remove(this.bottom);
 399             }
 400             this.bottom = null;
 401             return;
 402         }
 403         this.bottom = bottom;
 404         bottom.setParent(this, false);
 405         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 406                 getHeight()));
 407     }
 408
 409     /**
 410      * Remove a widget, regardless of what pane it is on.
 411      *
 412      * @param widget the widget to remove
 413      */
 414     public void removeWidget(final TWidget widget) {
 415         if (widget == null) {
 416             throw new IllegalArgumentException("cannot remove null widget");
 417         }
 418         if (left == widget) {
 419             left = null;
 420             assert(right != widget);
 421             assert(top != widget);
 422             assert(bottom != widget);
 423             return;
 424         }
 425         if (right == widget) {
 426             right = null;
 427             assert(left != widget);
 428             assert(top != widget);
 429             assert(bottom != widget);
 430             return;
 431         }
 432         if (top == widget) {
 433             top = null;
 434             assert(left != widget);
 435             assert(right != widget);
 436             assert(bottom != widget);
 437             return;
 438         }
 439         if (bottom == widget) {
 440             bottom = null;
 441             assert(left != widget);
 442             assert(right != widget);
 443             assert(top != widget);
 444             return;
 445         }
 446         throw new IllegalArgumentException("widget " + widget +
 447             " not in this split");
 448     }
 449
 450     /**
 451      * Replace a widget, regardless of what pane it is on, with another
 452      * widget.
 453      *
 454      * @param oldWidget the widget to remove
 455      * @param newWidget the widget to replace it with
 456      */
 457     public void replaceWidget(final TWidget oldWidget,
 458         final TWidget newWidget) {
 459
 460         if (oldWidget == null) {
 461             throw new IllegalArgumentException("cannot remove null oldWidget");
 462         }
 463         if (left == oldWidget) {
 464             setLeft(newWidget);
 465             assert(right != newWidget);
 466             assert(top != newWidget);
 467             assert(bottom != newWidget);
 468             return;
 469         }
 470         if (right == oldWidget) {
 471             setRight(newWidget);
 472             assert(left != newWidget);
 473             assert(top != newWidget);
 474             assert(bottom != newWidget);
 475             return;
 476         }
 477         if (top == oldWidget) {
 478             setTop(newWidget);
 479             assert(left != newWidget);
 480             assert(right != newWidget);
 481             assert(bottom != newWidget);
 482             return;
 483         }
 484         if (bottom == oldWidget) {
 485             setBottom(newWidget);
 486             assert(left != newWidget);
 487             assert(right != newWidget);
 488             assert(top != newWidget);
 489             return;
 490         }
 491         throw new IllegalArgumentException("oldWidget " + oldWidget +
 492             " not in this split");
 493     }
 494
 495     /**
 496      * Layout the two child widgets.
 497      */
 498     private void layoutChildren() {
 499         if (vertical) {
 500             if (left != null) {
 501                 left.setDimensions(0, 0, split, getHeight());
 502                 left.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 503                         left.getWidth(), left.getHeight()));
 504             }
 505             if (right != null) {
 506                 right.setDimensions(split + 1, 0, getWidth() - split - 1,
 507                     getHeight());
 508                 right.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 509                         right.getWidth(), right.getHeight()));
 510             }
 511         } else {
 512             if (top != null) {
 513                 top.setDimensions(0, 0, getWidth(), split);
 514                 top.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 515                         top.getWidth(), top.getHeight()));
 516             }
 517             if (bottom != null) {
 518                 bottom.setDimensions(0, split + 1, getWidth(),
 519                     getHeight() - split - 1);
 520                 bottom.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 521                         bottom.getWidth(), bottom.getHeight()));
 522             }
 523         }
 524     }
 525
 526     /**
 527      * Recenter the split to the middle of this split pane.
 528      */
 529     public void center() {
 530         if (vertical) {
 531             split = getWidth() / 2;
 532         } else {
 533             split = getHeight() / 2;
 534         }
 535         layoutChildren();
 536     }
 537
 538     /**
 539      * Remove this split, removing the widget specified.
 540      *
 541      * @param widgetToRemove the widget to remove
 542      * @param doClose if true, call the close() method before removing the
 543      * child
 544      * @return the pane that remains, or null if nothing is retained
 545      */
 546     public TWidget removeSplit(final TWidget widgetToRemove,
 547         final boolean doClose) {
 548
 549         TWidget keep = null;
 550         if (vertical) {
 551             if ((widgetToRemove != left) && (widgetToRemove != right)) {
 552                 throw new IllegalArgumentException("widget to remove is not " +
 553                     "either of the panes in this splitpane");
 554             }
 555             if (widgetToRemove == left) {
 556                 keep = right;
 557             } else {
 558                 keep = left;
 559             }
 560
 561         } else {
 562             if ((widgetToRemove != top) && (widgetToRemove != bottom)) {
 563                 throw new IllegalArgumentException("widget to remove is not " +
 564                     "either of the panes in this splitpane");
 565             }
 566             if (widgetToRemove == top) {
 567                 keep = bottom;
 568             } else {
 569                 keep = top;
 570             }
 571         }
 572
 573         // Remove me from my parent widget.
 574         TWidget myParent = getParent();
 575         remove(false);
 576
 577         if (keep == null) {
 578             if (myParent instanceof TSplitPane) {
 579                 // TSplitPane has a left/right/top/bottom link to me
 580                 // somewhere, remove it.
 581                 ((TSplitPane) myParent).removeWidget(this);
 582             }
 583
 584             // Nothing is left of either pane.  Remove me and bail out.
 585             return null;
 586         }
 587
 588         if (myParent instanceof TSplitPane) {
 589             // TSplitPane has a left/right/top/bottom link to me
 590             // somewhere, replace me with keep.
 591             ((TSplitPane) myParent).replaceWidget(this, keep);
 592         } else {
 593             keep.setParent(myParent, false);
 594             keep.setDimensions(getX(), getY(), getWidth(), getHeight());
 595             keep.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 596                     getHeight()));
 597         }
 598
 599         return keep;
 600     }
 601
 602 }