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.getX() == split);
 151             } else {
 152                 inSplitMove = (mouse.getY() == 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.getX();
 203                 split = Math.min(Math.max(1, split), getWidth() - 2);
 204             } else {
 205                 split = mouse.getY();
 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     // TSplitPane -------------------------------------------------------------
 256     // ------------------------------------------------------------------------
 257
 258     /**
 259      * Get the widget on the left side.
 260      *
 261      * @return the widget on the left, or null if not set
 262      */
 263     public TWidget getLeft() {
 264         return left;
 265     }
 266
 267     /**
 268      * Set the widget on the left side.
 269      *
 270      * @param left the widget to set, or null to remove
 271      */
 272     public void setLeft(final TWidget left) {
 273         if (!vertical) {
 274             throw new IllegalArgumentException("cannot set left on " +
 275                 "horizontal split pane");
 276         }
 277         if (left == null) {
 278             if (this.left != null) {
 279                 remove(this.left);
 280             }
 281             this.left = null;
 282             return;
 283         }
 284         this.left = left;
 285         left.setParent(this, false);
 286         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 287                 getHeight()));
 288     }
 289
 290     /**
 291      * Get the widget on the right side.
 292      *
 293      * @return the widget on the right, or null if not set
 294      */
 295     public TWidget getRight() {
 296         return right;
 297     }
 298
 299     /**
 300      * Set the widget on the right side.
 301      *
 302      * @param right the widget to set, or null to remove
 303      */
 304     public void setRight(final TWidget right) {
 305         if (!vertical) {
 306             throw new IllegalArgumentException("cannot set right on " +
 307                 "horizontal split pane");
 308         }
 309         if (right == null) {
 310             if (this.right != null) {
 311                 remove(this.right);
 312             }
 313             this.right = null;
 314             return;
 315         }
 316         this.right = right;
 317         right.setParent(this, false);
 318         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 319                 getHeight()));
 320     }
 321
 322     /**
 323      * Get the widget on the top side.
 324      *
 325      * @return the widget on the top, or null if not set
 326      */
 327     public TWidget getTop() {
 328         return top;
 329     }
 330
 331     /**
 332      * Set the widget on the top side.
 333      *
 334      * @param top the widget to set, or null to remove
 335      */
 336     public void setTop(final TWidget top) {
 337         if (vertical) {
 338             throw new IllegalArgumentException("cannot set top on vertical " +
 339                 "split pane");
 340         }
 341         if (top == null) {
 342             if (this.top != null) {
 343                 remove(this.top);
 344             }
 345             this.top = null;
 346             return;
 347         }
 348         this.top = top;
 349         top.setParent(this, false);
 350         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 351                 getHeight()));
 352     }
 353
 354     /**
 355      * Get the widget on the bottom side.
 356      *
 357      * @return the widget on the bottom, or null if not set
 358      */
 359     public TWidget getBottom() {
 360         return bottom;
 361     }
 362
 363     /**
 364      * Set the widget on the bottom side.
 365      *
 366      * @param bottom the widget to set, or null to remove
 367      */
 368     public void setBottom(final TWidget bottom) {
 369         if (vertical) {
 370             throw new IllegalArgumentException("cannot set bottom on " +
 371                 "vertical split pane");
 372         }
 373         if (bottom == null) {
 374             if (this.bottom != null) {
 375                 remove(this.bottom);
 376             }
 377             this.bottom = null;
 378             return;
 379         }
 380         this.bottom = bottom;
 381         bottom.setParent(this, false);
 382         onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 383                 getHeight()));
 384     }
 385
 386     /**
 387      * Layout the two child widgets.
 388      */
 389     private void layoutChildren() {
 390         if (vertical) {
 391             if (left != null) {
 392                 left.setDimensions(0, 0, split, getHeight());
 393                 left.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 394                         left.getWidth(), left.getHeight()));
 395             }
 396             if (right != null) {
 397                 right.setDimensions(split + 1, 0, getWidth() - split - 1,
 398                     getHeight());
 399                 right.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 400                         right.getWidth(), right.getHeight()));
 401             }
 402         } else {
 403             if (top != null) {
 404                 top.setDimensions(0, 0, getWidth(), split);
 405                 top.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 406                         top.getWidth(), top.getHeight()));
 407             }
 408             if (bottom != null) {
 409                 bottom.setDimensions(0, split + 1, getWidth(),
 410                     getHeight() - split - 1);
 411                 bottom.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET,
 412                         bottom.getWidth(), bottom.getHeight()));
 413             }
 414         }
 415     }
 416
 417     /**
 418      * Recenter the split to the middle of this split pane.
 419      */
 420     public void center() {
 421         if (vertical) {
 422             split = getWidth() / 2;
 423         } else {
 424             split = getHeight() / 2;
 425         }
 426         layoutChildren();
 427     }
 428
 429     /**
 430      * Remove this split, removing the widget specified.
 431      *
 432      * @param widgetToRemove the widget to remove
 433      * @param doClose if true, call the close() method before removing the
 434      * child
 435      * @return the pane that remains, or null if nothing is retained
 436      */
 437     public TWidget removeSplit(final TWidget widgetToRemove,
 438         final boolean doClose) {
 439
 440         TWidget keep = null;
 441         if (vertical) {
 442             if ((widgetToRemove != left) && (widgetToRemove != right)) {
 443                 throw new IllegalArgumentException("widget to remove is not " +
 444                     "either of the panes in this splitpane");
 445             }
 446             if (widgetToRemove == left) {
 447                 keep = right;
 448             } else {
 449                 keep = left;
 450             }
 451
 452         } else {
 453             if ((widgetToRemove != top) && (widgetToRemove != bottom)) {
 454                 throw new IllegalArgumentException("widget to remove is not " +
 455                     "either of the panes in this splitpane");
 456             }
 457             if (widgetToRemove == top) {
 458                 keep = bottom;
 459             } else {
 460                 keep = top;
 461             }
 462         }
 463
 464         // Remove me from my parent widget.
 465         TWidget newParent = getParent();
 466         remove(false);
 467
 468         if (keep == null) {
 469             // Nothing is left of either pane.  Remove me and bail out.
 470             return null;
 471         }
 472
 473         keep.setParent(newParent, false);
 474         keep.setDimensions(getX(), getY(), getWidth(), getHeight());
 475         keep.onResize(new TResizeEvent(TResizeEvent.Type.WIDGET, getWidth(),
 476                 getHeight()));
 477
 478         return keep;
 479     }
 480
 481 }