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