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 TScrollableWidget {
  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      * Maximum width of a single line.
 100      */
 101     private int maxLineWidth;
 102
 103     /**
 104      * Number of lines between each paragraph.
 105      */
 106     private int lineSpacing = 1;
 107
 108     /**
 109      * Set the text.
 110      *
 111      * @param text new text to display
 112      */
 113     public void setText(final String text) {
 114         this.text = text;
 115         reflowData();
 116     }
 117
 118     /**
 119      * Get the text.
 120      *
 121      * @return the text
 122      */
 123     public String getText() {
 124         return text;
 125     }
 126
 127     /**
 128      * Convenience method used by TWindowLoggerOutput.
 129      *
 130      * @param line new line to add
 131      */
 132     public void addLine(final String line) {
 133         if (text.length() == 0) {
 134             text = line;
 135         } else {
 136             text += "\n\n";
 137             text += line;
 138         }
 139         reflowData();
 140     }
 141
 142     /**
 143      * Recompute the bounds for the scrollbars.
 144      */
 145     private void computeBounds() {
 146         maxLineWidth = 0;
 147         for (String line : lines) {
 148             if (line.length() > maxLineWidth) {
 149                 maxLineWidth = line.length();
 150             }
 151         }
 152
 153         vScroller.setTopValue(0);
 154         vScroller.setBottomValue((lines.size() - getHeight()) + 1);
 155         if (vScroller.getBottomValue() < 0) {
 156             vScroller.setBottomValue(0);
 157         }
 158         if (vScroller.getValue() > vScroller.getBottomValue()) {
 159             vScroller.setValue(vScroller.getBottomValue());
 160         }
 161
 162         hScroller.setLeftValue(0);
 163         hScroller.setRightValue((maxLineWidth - getWidth()) + 1);
 164         if (hScroller.getRightValue() < 0) {
 165             hScroller.setRightValue(0);
 166         }
 167         if (hScroller.getValue() > hScroller.getRightValue()) {
 168             hScroller.setValue(hScroller.getRightValue());
 169         }
 170     }
 171
 172     /**
 173      * Set justification.
 174      *
 175      * @param justification LEFT, CENTER, RIGHT, or FULL
 176      */
 177     public void setJustification(final Justification justification) {
 178         this.justification = justification;
 179         reflowData();
 180     }
 181
 182     /**
 183      * Left-justify the text.
 184      */
 185     public void leftJustify() {
 186         justification = Justification.LEFT;
 187         reflowData();
 188     }
 189
 190     /**
 191      * Center-justify the text.
 192      */
 193     public void centerJustify() {
 194         justification = Justification.CENTER;
 195         reflowData();
 196     }
 197
 198     /**
 199      * Right-justify the text.
 200      */
 201     public void rightJustify() {
 202         justification = Justification.RIGHT;
 203         reflowData();
 204     }
 205
 206     /**
 207      * Fully-justify the text.
 208      */
 209     public void fullJustify() {
 210         justification = Justification.FULL;
 211         reflowData();
 212     }
 213
 214     /**
 215      * Resize text and scrollbars for a new width/height.
 216      */
 217     @Override
 218     public void reflowData() {
 219         // Reset the lines
 220         lines.clear();
 221
 222         // Break up text into paragraphs
 223         String[] paragraphs = text.split("\n\n");
 224         for (String p : paragraphs) {
 225             switch (justification) {
 226             case LEFT:
 227                 lines.addAll(jexer.bits.StringJustifier.left(p,
 228                         getWidth() - 1));
 229                 break;
 230             case CENTER:
 231                 lines.addAll(jexer.bits.StringJustifier.center(p,
 232                         getWidth() - 1));
 233                 break;
 234             case RIGHT:
 235                 lines.addAll(jexer.bits.StringJustifier.right(p,
 236                         getWidth() - 1));
 237                 break;
 238             case FULL:
 239                 lines.addAll(jexer.bits.StringJustifier.full(p,
 240                         getWidth() - 1));
 241                 break;
 242             }
 243
 244             for (int i = 0; i < lineSpacing; i++) {
 245                 lines.add("");
 246             }
 247         }
 248         computeBounds();
 249     }
 250
 251     /**
 252      * Public constructor.
 253      *
 254      * @param parent parent widget
 255      * @param text text on the screen
 256      * @param x column relative to parent
 257      * @param y row relative to parent
 258      * @param width width of text area
 259      * @param height height of text area
 260      */
 261     public TText(final TWidget parent, final String text, final int x,
 262             final int y, final int width, final int height) {
 263
 264         this(parent, text, x, y, width, height, "ttext");
 265     }
 266
 267     /**
 268      * Public constructor.
 269      *
 270      * @param parent parent widget
 271      * @param text text on the screen
 272      * @param x column relative to parent
 273      * @param y row relative to parent
 274      * @param width width of text area
 275      * @param height height of text area
 276      * @param colorKey ColorTheme key color to use for foreground
 277      * text. Default is "ttext".
 278      */
 279     public TText(final TWidget parent, final String text, final int x,
 280             final int y, final int width, final int height,
 281             final String colorKey) {
 282
 283         // Set parent and window
 284         super(parent, x, y, width, height);
 285
 286         this.text = text;
 287         this.colorKey = colorKey;
 288
 289         lines = new LinkedList<String>();
 290
 291         vScroller = new TVScroller(this, getWidth() - 1, 0, getHeight() - 1);
 292         hScroller = new THScroller(this, 0, getHeight() - 1, getWidth() - 1);
 293         reflowData();
 294     }
 295
 296     /**
 297      * Draw the text box.
 298      */
 299     @Override
 300     public void draw() {
 301         // Setup my color
 302         CellAttributes color = getTheme().getColor(colorKey);
 303
 304         int begin = vScroller.getValue();
 305         int topY = 0;
 306         for (int i = begin; i < lines.size(); i++) {
 307             String line = lines.get(i);
 308             if (hScroller.getValue() < line.length()) {
 309                 line = line.substring(hScroller.getValue());
 310             } else {
 311                 line = "";
 312             }
 313             String formatString = "%-" + Integer.toString(getWidth() - 1) + "s";
 314             getScreen().putStringXY(0, topY, String.format(formatString, line),
 315                     color);
 316             topY++;
 317
 318             if (topY >= (getHeight() - 1)) {
 319                 break;
 320             }
 321         }
 322
 323         // Pad the rest with blank lines
 324         for (int i = topY; i < (getHeight() - 1); i++) {
 325             getScreen().hLineXY(0, i, getWidth() - 1, ' ', color);
 326         }
 327
 328     }
 329
 330     /**
 331      * Handle mouse press events.
 332      *
 333      * @param mouse mouse button press event
 334      */
 335     @Override
 336     public void onMouseDown(final TMouseEvent mouse) {
 337         if (mouse.isMouseWheelUp()) {
 338             vScroller.decrement();
 339             return;
 340         }
 341         if (mouse.isMouseWheelDown()) {
 342             vScroller.increment();
 343             return;
 344         }
 345
 346         // Pass to children
 347         super.onMouseDown(mouse);
 348     }
 349
 350     /**
 351      * Handle keystrokes.
 352      *
 353      * @param keypress keystroke event
 354      */
 355     @Override
 356     public void onKeypress(final TKeypressEvent keypress) {
 357         if (keypress.equals(kbLeft)) {
 358             hScroller.decrement();
 359         } else if (keypress.equals(kbRight)) {
 360             hScroller.increment();
 361         } else if (keypress.equals(kbUp)) {
 362             vScroller.decrement();
 363         } else if (keypress.equals(kbDown)) {
 364             vScroller.increment();
 365         } else if (keypress.equals(kbPgUp)) {
 366             vScroller.bigDecrement();
 367         } else if (keypress.equals(kbPgDn)) {
 368             vScroller.bigIncrement();
 369         } else if (keypress.equals(kbHome)) {
 370             vScroller.toTop();
 371         } else if (keypress.equals(kbEnd)) {
 372             vScroller.toBottom();
 373         } else {
 374             // Pass other keys (tab etc.) on
 375             super.onKeypress(keypress);
 376         }
 377     }
 378
 379 }