src/jexer/TText.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 java.util.Arrays;
  32 import java.util.LinkedList;
  33 import java.util.List;
  34
  35 import jexer.bits.CellAttributes;
  36 import jexer.bits.StringUtils;
  37 import jexer.event.TKeypressEvent;
  38 import jexer.event.TMouseEvent;
  39 import static jexer.TKeypress.kbDown;
  40 import static jexer.TKeypress.kbEnd;
  41 import static jexer.TKeypress.kbHome;
  42 import static jexer.TKeypress.kbLeft;
  43 import static jexer.TKeypress.kbPgDn;
  44 import static jexer.TKeypress.kbPgUp;
  45 import static jexer.TKeypress.kbRight;
  46 import static jexer.TKeypress.kbUp;
  47
  48 /**
  49  * TText implements a simple scrollable text area. It reflows automatically on
  50  * resize.
  51  */
  52 public class TText extends TScrollableWidget {
  53
  54     // ------------------------------------------------------------------------
  55     // Constants --------------------------------------------------------------
  56     // ------------------------------------------------------------------------
  57
  58     /**
  59      * Available text justifications.
  60      */
  61     public enum Justification {
  62
  63         /**
  64          * Not justified at all, use spacing as provided by the client.
  65          */
  66         NONE,
  67
  68         /**
  69          * Left-justified text.
  70          */
  71         LEFT,
  72
  73         /**
  74          * Centered text.
  75          */
  76         CENTER,
  77
  78         /**
  79          * Right-justified text.
  80          */
  81         RIGHT,
  82
  83         /**
  84          * Fully-justified text.
  85          */
  86         FULL,
  87     }
  88
  89     // ------------------------------------------------------------------------
  90     // Variables --------------------------------------------------------------
  91     // ------------------------------------------------------------------------
  92
  93     /**
  94      * How to justify the text.
  95      */
  96     private Justification justification = Justification.LEFT;
  97
  98     /**
  99      * Text to display.
 100      */
 101     private String text;
 102
 103     /**
 104      * Text converted to lines.
 105      */
 106     private List<String> lines;
 107
 108     /**
 109      * Text color.
 110      */
 111     private String colorKey;
 112
 113     /**
 114      * Maximum width of a single line.
 115      */
 116     private int maxLineWidth;
 117
 118     /**
 119      * Number of lines between each paragraph.
 120      */
 121     private int lineSpacing = 1;
 122
 123     // ------------------------------------------------------------------------
 124     // Constructors -----------------------------------------------------------
 125     // ------------------------------------------------------------------------
 126
 127     /**
 128      * Public constructor.
 129      *
 130      * @param parent parent widget
 131      * @param text text on the screen
 132      * @param x column relative to parent
 133      * @param y row relative to parent
 134      * @param width width of text area
 135      * @param height height of text area
 136      */
 137     public TText(final TWidget parent, final String text, final int x,
 138             final int y, final int width, final int height) {
 139
 140         this(parent, text, x, y, width, height, "ttext");
 141     }
 142
 143     /**
 144      * Public constructor.
 145      *
 146      * @param parent parent widget
 147      * @param text text on the screen
 148      * @param x column relative to parent
 149      * @param y row relative to parent
 150      * @param width width of text area
 151      * @param height height of text area
 152      * @param colorKey ColorTheme key color to use for foreground
 153      * text. Default is "ttext".
 154      */
 155     public TText(final TWidget parent, final String text, final int x,
 156             final int y, final int width, final int height,
 157             final String colorKey) {
 158
 159         // Set parent and window
 160         super(parent, x, y, width, height);
 161
 162         this.text = text;
 163         this.colorKey = colorKey;
 164
 165         lines = new LinkedList<String>();
 166
 167         vScroller = new TVScroller(this, getWidth() - 1, 0, getHeight() - 1);
 168         hScroller = new THScroller(this, 0, getHeight() - 1, getWidth() - 1);
 169         reflowData();
 170     }
 171
 172     // ------------------------------------------------------------------------
 173     // TScrollableWidget ------------------------------------------------------
 174     // ------------------------------------------------------------------------
 175
 176     /**
 177      * Draw the text box.
 178      */
 179     @Override
 180     public void draw() {
 181         // Setup my color
 182         CellAttributes color = getTheme().getColor(colorKey);
 183
 184         int begin = vScroller.getValue();
 185         int topY = 0;
 186         for (int i = begin; i < lines.size(); i++) {
 187             String line = lines.get(i);
 188             if (hScroller.getValue() < StringUtils.width(line)) {
 189                 line = line.substring(hScroller.getValue());
 190             } else {
 191                 line = "";
 192             }
 193             String formatString = "%-" + Integer.toString(getWidth() - 1) + "s";
 194             putStringXY(0, topY, String.format(formatString, line), color);
 195             topY++;
 196
 197             if (topY >= (getHeight() - 1)) {
 198                 break;
 199             }
 200         }
 201
 202         // Pad the rest with blank lines
 203         for (int i = topY; i < (getHeight() - 1); i++) {
 204             hLineXY(0, i, getWidth() - 1, ' ', color);
 205         }
 206
 207     }
 208
 209     /**
 210      * Handle mouse press events.
 211      *
 212      * @param mouse mouse button press event
 213      */
 214     @Override
 215     public void onMouseDown(final TMouseEvent mouse) {
 216         if (mouse.isMouseWheelUp()) {
 217             vScroller.decrement();
 218             return;
 219         }
 220         if (mouse.isMouseWheelDown()) {
 221             vScroller.increment();
 222             return;
 223         }
 224
 225         // Pass to children
 226         super.onMouseDown(mouse);
 227     }
 228
 229     /**
 230      * Handle keystrokes.
 231      *
 232      * @param keypress keystroke event
 233      */
 234     @Override
 235     public void onKeypress(final TKeypressEvent keypress) {
 236         if (keypress.equals(kbLeft)) {
 237             hScroller.decrement();
 238         } else if (keypress.equals(kbRight)) {
 239             hScroller.increment();
 240         } else if (keypress.equals(kbUp)) {
 241             vScroller.decrement();
 242         } else if (keypress.equals(kbDown)) {
 243             vScroller.increment();
 244         } else if (keypress.equals(kbPgUp)) {
 245             vScroller.bigDecrement();
 246         } else if (keypress.equals(kbPgDn)) {
 247             vScroller.bigIncrement();
 248         } else if (keypress.equals(kbHome)) {
 249             vScroller.toTop();
 250         } else if (keypress.equals(kbEnd)) {
 251             vScroller.toBottom();
 252         } else {
 253             // Pass other keys (tab etc.) on
 254             super.onKeypress(keypress);
 255         }
 256     }
 257
 258     /**
 259      * Resize text and scrollbars for a new width/height.
 260      */
 261     @Override
 262     public void reflowData() {
 263         // Reset the lines
 264         lines.clear();
 265
 266         // Break up text into paragraphs
 267         String[] paragraphs = text.split("\n\n");
 268         for (String p : paragraphs) {
 269             switch (justification) {
 270             case NONE:
 271                 lines.addAll(Arrays.asList(p.split("\n")));
 272                 break;
 273             case LEFT:
 274                 lines.addAll(jexer.bits.StringUtils.left(p,
 275                         getWidth() - 1));
 276                 break;
 277             case CENTER:
 278                 lines.addAll(jexer.bits.StringUtils.center(p,
 279                         getWidth() - 1));
 280                 break;
 281             case RIGHT:
 282                 lines.addAll(jexer.bits.StringUtils.right(p,
 283                         getWidth() - 1));
 284                 break;
 285             case FULL:
 286                 lines.addAll(jexer.bits.StringUtils.full(p,
 287                         getWidth() - 1));
 288                 break;
 289             }
 290
 291             for (int i = 0; i < lineSpacing; i++) {
 292                 lines.add("");
 293             }
 294         }
 295         computeBounds();
 296     }
 297
 298     // ------------------------------------------------------------------------
 299     // TText ------------------------------------------------------------------
 300     // ------------------------------------------------------------------------
 301
 302     /**
 303      * Set the text.
 304      *
 305      * @param text new text to display
 306      */
 307     public void setText(final String text) {
 308         this.text = text;
 309         reflowData();
 310     }
 311
 312     /**
 313      * Get the text.
 314      *
 315      * @return the text
 316      */
 317     public String getText() {
 318         return text;
 319     }
 320
 321     /**
 322      * Convenience method used by TWindowLoggerOutput.
 323      *
 324      * @param line new line to add
 325      */
 326     public void addLine(final String line) {
 327         if (StringUtils.width(text) == 0) {
 328             text = line;
 329         } else {
 330             text += "\n\n";
 331             text += line;
 332         }
 333         reflowData();
 334     }
 335
 336     /**
 337      * Recompute the bounds for the scrollbars.
 338      */
 339     private void computeBounds() {
 340         maxLineWidth = 0;
 341         for (String line : lines) {
 342             if (StringUtils.width(line) > maxLineWidth) {
 343                 maxLineWidth = StringUtils.width(line);
 344             }
 345         }
 346
 347         vScroller.setTopValue(0);
 348         vScroller.setBottomValue((lines.size() - getHeight()) + 1);
 349         if (vScroller.getBottomValue() < 0) {
 350             vScroller.setBottomValue(0);
 351         }
 352         if (vScroller.getValue() > vScroller.getBottomValue()) {
 353             vScroller.setValue(vScroller.getBottomValue());
 354         }
 355
 356         hScroller.setLeftValue(0);
 357         hScroller.setRightValue((maxLineWidth - getWidth()) + 1);
 358         if (hScroller.getRightValue() < 0) {
 359             hScroller.setRightValue(0);
 360         }
 361         if (hScroller.getValue() > hScroller.getRightValue()) {
 362             hScroller.setValue(hScroller.getRightValue());
 363         }
 364     }
 365
 366     /**
 367      * Set justification.
 368      *
 369      * @param justification LEFT, CENTER, RIGHT, or FULL
 370      */
 371     public void setJustification(final Justification justification) {
 372         this.justification = justification;
 373         reflowData();
 374     }
 375
 376     /**
 377      * Left-justify the text.
 378      */
 379     public void leftJustify() {
 380         justification = Justification.LEFT;
 381         reflowData();
 382     }
 383
 384     /**
 385      * Center-justify the text.
 386      */
 387     public void centerJustify() {
 388         justification = Justification.CENTER;
 389         reflowData();
 390     }
 391
 392     /**
 393      * Right-justify the text.
 394      */
 395     public void rightJustify() {
 396         justification = Justification.RIGHT;
 397         reflowData();
 398     }
 399
 400     /**
 401      * Fully-justify the text.
 402      */
 403     public void fullJustify() {
 404         justification = Justification.FULL;
 405         reflowData();
 406     }
 407
 408 }