src/jexer/bits/MnemonicString.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.bits;
  30
  31 /**
  32  * MnemonicString is used to render a string like "&amp;File" into a
  33  * highlighted 'F' and the rest of 'ile'.  To insert a literal '&amp;', use
  34  * two '&amp;&amp;' characters, e.g. "&amp;File &amp;&amp; Stuff" would be
  35  * "File &amp; Stuff" with the first 'F' highlighted.
  36  */
  37 public class MnemonicString {
  38
  39     // ------------------------------------------------------------------------
  40     // Variables --------------------------------------------------------------
  41     // ------------------------------------------------------------------------
  42
  43     /**
  44      * Keyboard shortcut to activate this item.
  45      */
  46     private int shortcut;
  47
  48     /**
  49      * Location of the highlighted character.
  50      */
  51     private int shortcutIdx = -1;
  52
  53     /**
  54      * Screen location of the highlighted character (number of text cells
  55      * required to display from the beginning to shortcutIdx).
  56      */
  57     private int screenShortcutIdx = -1;
  58
  59     /**
  60      * The raw (uncolored) string.
  61      */
  62     private String rawLabel;
  63
  64     // ------------------------------------------------------------------------
  65     // Constructors -----------------------------------------------------------
  66     // ------------------------------------------------------------------------
  67
  68     /**
  69      * Public constructor.
  70      *
  71      * @param label widget label or title.  Label must contain a keyboard
  72      * shortcut, denoted by prefixing a letter with "&amp;", e.g. "&amp;File"
  73      */
  74     public MnemonicString(final String label) {
  75
  76         // Setup the menu shortcut
  77         StringBuilder newLabel = new StringBuilder();
  78         boolean foundAmp = false;
  79         boolean foundShortcut = false;
  80         int scanShortcutIdx = 0;
  81         int scanScreenShortcutIdx = 0;
  82         for (int i = 0; i < label.length();) {
  83             int c = label.codePointAt(i);
  84             i += Character.charCount(c);
  85
  86             if (c == '&') {
  87                 if (foundAmp) {
  88                     newLabel.append('&');
  89                     scanShortcutIdx++;
  90                     scanScreenShortcutIdx++;
  91                 } else {
  92                     foundAmp = true;
  93                 }
  94             } else {
  95                 newLabel.append(Character.toChars(c));
  96                 if (foundAmp) {
  97                     if (!foundShortcut) {
  98                         shortcut = c;
  99                         foundAmp = false;
 100                         foundShortcut = true;
 101                         shortcutIdx = scanShortcutIdx;
 102                         screenShortcutIdx = scanScreenShortcutIdx;
 103                     }
 104                 } else {
 105                     scanShortcutIdx++;
 106                     scanScreenShortcutIdx += StringUtils.width(c);
 107                 }
 108             }
 109         }
 110         this.rawLabel = newLabel.toString();
 111     }
 112
 113     // ------------------------------------------------------------------------
 114     // MnemonicString ---------------------------------------------------------
 115     // ------------------------------------------------------------------------
 116
 117     /**
 118      * Get the keyboard shortcut character.
 119      *
 120      * @return the highlighted character
 121      */
 122     public int getShortcut() {
 123         return shortcut;
 124     }
 125
 126     /**
 127      * Get location of the highlighted character.
 128      *
 129      * @return location of the highlighted character
 130      */
 131     public int getShortcutIdx() {
 132         return shortcutIdx;
 133     }
 134
 135     /**
 136      * Get the screen location of the highlighted character.
 137      *
 138      * @return the number of text cells required to display from the
 139      * beginning of the label to shortcutIdx
 140      */
 141     public int getScreenShortcutIdx() {
 142         return screenShortcutIdx;
 143     }
 144
 145     /**
 146      * Get the raw (uncolored) string.
 147      *
 148      * @return the raw (uncolored) string
 149      */
 150     public String getRawLabel() {
 151         return rawLabel;
 152     }
 153
 154 }