src/jexer/TText.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2017 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 static jexer.TKeypress.kbDown;
  32 import static jexer.TKeypress.kbEnd;
  33 import static jexer.TKeypress.kbHome;
  34 import static jexer.TKeypress.kbLeft;
  35 import static jexer.TKeypress.kbPgDn;
  36 import static jexer.TKeypress.kbPgUp;
  37 import static jexer.TKeypress.kbRight;
  38 import static jexer.TKeypress.kbUp;
  39
  40 import java.util.LinkedList;
  41 import java.util.List;
  42
  43 import jexer.bits.CellAttributes;
  44 import jexer.event.TKeypressEvent;
  45 import jexer.event.TMouseEvent;
  46
  47 /**
  48  * TText implements a simple scrollable text area. It reflows automatically on
  49  * resize.
  50  */
  51 public final class TText extends TWidget {
  52
  53     /**
  54      * Available text justifications.
  55      */
  56     public enum Justification {
  57         /**
  58          * Left-justified text.
  59          */
  60         LEFT,
  61
  62         /**
  63          * Centered text.
  64          */
  65         CENTER,
  66
  67         /**
  68          * Right-justified text.
  69          */
  70         RIGHT,
  71
  72         /**
  73          * Fully-justified text.
  74          */
  75         FULL,
  76     }
  77
  78     /**
  79      * How to justify the text.
  80      */
  81     private Justification justification = Justification.LEFT;
  82
  83     /**
  84      * Text to display.
  85      */
  86     private String text;
  87
  88     /**
  89      * Text converted to lines.
  90      */
  91     private List<String> lines;
  92
  93     /**
  94      * Text color.
  95      */
  96     private String colorKey;
  97
  98     /**
  99      * Vertical scrollbar.
 100      */
 101     private TVScroller vScroller;
 102
 103     /**
 104      * Horizontal scrollbar.
 105      */
 106     private THScroller hScroller;
 107
 108     /**
 109      * Maximum width of a single line.
 110      */
 111     private int maxLineWidth;
 112
 113     /**
 114      * Number of lines between each paragraph.
 115      */
 116     private int lineSpacing = 1;
 117
 118     /**
 119      * Convenience method used by TWindowLoggerOutput.
 120      *
 121      * @param line new line to add
 122      */
 123     public void addLine(final String line) {
 124         if (text.length() == 0) {
 125             text = line;
 126         } else {
 127             text += "\n\n";
 128             text += line;
 129         }
 130         reflow();
 131     }
 132
 133     /**
 134      * Recompute the bounds for the scrollbars.
 135      */
 136     private void computeBounds() {
 137         maxLineWidth = 0;
 138         for (String line : lines) {
 139             if (line.length() > maxLineWidth) {
 140                 maxLineWidth = line.length();
 141             }
 142         }
 143
 144         vScroller.setBottomValue((lines.size() - getHeight()) + 1);
 145         if (vScroller.getBottomValue() < 0) {
 146             vScroller.setBottomValue(0);
 147         }
 148         if (vScroller.getValue() > vScroller.getBottomValue()) {
 149             vScroller.setValue(vScroller.getBottomValue());
 150         }
 151
 152         hScroller.setRightValue((maxLineWidth - getWidth()) + 1);
 153         if (hScroller.getRightValue() < 0) {
 154             hScroller.setRightValue(0);
 155         }
 156         if (hScroller.getValue() > hScroller.getRightValue()) {
 157             hScroller.setValue(hScroller.getRightValue());
 158         }
 159     }
 160
 161     /**
 162      * Set justification.
 163      *
 164      * @param justification LEFT, CENTER, RIGHT, or FULL
 165      */
 166     public void setJustification(final Justification justification) {
 167         this.justification = justification;
 168         reflow();
 169     }
 170
 171     /**
 172      * Left-justify the text.
 173      */
 174     public void leftJustify() {
 175         justification = Justification.LEFT;
 176         reflow();
 177     }
 178
 179     /**
 180      * Center-justify the text.
 181      */
 182     public void centerJustify() {
 183         justification = Justification.CENTER;
 184         reflow();
 185     }
 186
 187     /**
 188      * Right-justify the text.
 189      */
 190     public void rightJustify() {
 191         justification = Justification.RIGHT;
 192         reflow();
 193     }
 194
 195     /**
 196      * Fully-justify the text.
 197      */
 198     public void fullJustify() {
 199         justification = Justification.FULL;
 200         reflow();
 201     }
 202
 203     /**
 204      * Resize text and scrollbars for a new width/height.
 205      */
 206     public void reflow() {
 207         // Reset the lines
 208         lines.clear();
 209
 210         // Break up text into paragraphs
 211         String[] paragraphs = text.split("\n\n");
 212         for (String p : paragraphs) {
 213             switch (justification) {
 214             case LEFT:
 215                 lines.addAll(jexer.bits.StringJustifier.left(p,
 216                         getWidth() - 1));
 217                 break;
 218             case CENTER:
 219                 lines.addAll(jexer.bits.StringJustifier.center(p,
 220                         getWidth() - 1));
 221                 break;
 222             case RIGHT:
 223                 lines.addAll(jexer.bits.StringJustifier.right(p,
 224                         getWidth() - 1));
 225                 break;
 226             case FULL:
 227                 lines.addAll(jexer.bits.StringJustifier.full(p,
 228                         getWidth() - 1));
 229                 break;
 230             }
 231
 232             for (int i = 0; i < lineSpacing; i++) {
 233                 lines.add("");
 234             }
 235         }
 236
 237         // Start at the top
 238         if (vScroller == null) {
 239             vScroller = new TVScroller(this, getWidth() - 1, 0, getHeight() - 1);
 240             vScroller.setTopValue(0);
 241             vScroller.setValue(0);
 242         } else {
 243             vScroller.setX(getWidth() - 1);
 244             vScroller.setHeight(getHeight() - 1);
 245         }
 246         vScroller.setBigChange(getHeight() - 1);
 247
 248         // Start at the left
 249         if (hScroller == null) {
 250             hScroller = new THScroller(this, 0, getHeight() - 1, getWidth() - 1);
 251             hScroller.setLeftValue(0);
 252             hScroller.setValue(0);
 253         } else {
 254             hScroller.setY(getHeight() - 1);
 255             hScroller.setWidth(getWidth() - 1);
 256         }
 257         hScroller.setBigChange(getWidth() - 1);
 258
 259         computeBounds();
 260     }
 261
 262     /**
 263      * Public constructor.
 264      *
 265      * @param parent parent widget
 266      * @param text text on the screen
 267      * @param x column relative to parent
 268      * @param y row relative to parent
 269      * @param width width of text area
 270      * @param height height of text area
 271      */
 272     public TText(final TWidget parent, final String text, final int x,
 273             final int y, final int width, final int height) {
 274
 275         this(parent, text, x, y, width, height, "ttext");
 276     }
 277
 278     /**
 279      * Public constructor.
 280      *
 281      * @param parent parent widget
 282      * @param text text on the screen
 283      * @param x column relative to parent
 284      * @param y row relative to parent
 285      * @param width width of text area
 286      * @param height height of text area
 287      * @param colorKey ColorTheme key color to use for foreground
 288      * text. Default is "ttext".
 289      */
 290     public TText(final TWidget parent, final String text, final int x,
 291             final int y, final int width, final int height,
 292             final String colorKey) {
 293
 294         // Set parent and window
 295         super(parent, x, y, width, height);
 296
 297         this.text = text;
 298         this.colorKey = colorKey;
 299
 300         lines = new LinkedList<String>();
 301
 302         reflow();
 303     }
 304
 305     /**
 306      * Draw the text box.
 307      */
 308     @Override
 309     public void draw() {
 310         // Setup my color
 311         CellAttributes color = getTheme().getColor(colorKey);
 312
 313         int begin = vScroller.getValue();
 314         int topY = 0;
 315         for (int i = begin; i < lines.size(); i++) {
 316             String line = lines.get(i);
 317             if (hScroller.getValue() < line.length()) {
 318                 line = line.substring(hScroller.getValue());
 319             } else {
 320                 line = "";
 321             }
 322             String formatString = "%-" + Integer.toString(getWidth() - 1) + "s";
 323             getScreen().putStringXY(0, topY, String.format(formatString, line),
 324                     color);
 325             topY++;
 326
 327             if (topY >= (getHeight() - 1)) {
 328                 break;
 329             }
 330         }
 331
 332         // Pad the rest with blank lines
 333         for (int i = topY; i < (getHeight() - 1); i++) {
 334             getScreen().hLineXY(0, i, getWidth() - 1, ' ', color);
 335         }
 336
 337     }
 338
 339     /**
 340      * Handle mouse press events.
 341      *
 342      * @param mouse mouse button press event
 343      */
 344     @Override
 345     public void onMouseDown(final TMouseEvent mouse) {
 346         if (mouse.isMouseWheelUp()) {
 347             vScroller.decrement();
 348             return;
 349         }
 350         if (mouse.isMouseWheelDown()) {
 351             vScroller.increment();
 352             return;
 353         }
 354
 355         // Pass to children
 356         super.onMouseDown(mouse);
 357     }
 358
 359     /**
 360      * Handle keystrokes.
 361      *
 362      * @param keypress keystroke event
 363      */
 364     @Override
 365     public void onKeypress(final TKeypressEvent keypress) {
 366         if (keypress.equals(kbLeft)) {
 367             hScroller.decrement();
 368         } else if (keypress.equals(kbRight)) {
 369             hScroller.increment();
 370         } else if (keypress.equals(kbUp)) {
 371             vScroller.decrement();
 372         } else if (keypress.equals(kbDown)) {
 373             vScroller.increment();
 374         } else if (keypress.equals(kbPgUp)) {
 375             vScroller.bigDecrement();
 376         } else if (keypress.equals(kbPgDn)) {
 377             vScroller.bigIncrement();
 378         } else if (keypress.equals(kbHome)) {
 379             vScroller.toTop();
 380         } else if (keypress.equals(kbEnd)) {
 381             vScroller.toBottom();
 382         } else {
 383             // Pass other keys (tab etc.) on
 384             super.onKeypress(keypress);
 385         }
 386     }
 387
 388 }