src/jexer/bits/MnemonicString.java

   1 /**
   2  * Jexer - Java Text User Interface
   3  *
   4  * License: LGPLv3 or later
   5  *
   6  * This module is licensed under the GNU Lesser General Public License
   7  * Version 3.  Please see the file "COPYING" in this directory for more
   8  * information about the GNU Lesser General Public License Version 3.
   9  *
  10  *     Copyright (C) 2015  Kevin Lamonte
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public License
  14  * as published by the Free Software Foundation; either version 3 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this program; if not, see
  24  * http://www.gnu.org/licenses/, or write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  26  * 02110-1301 USA
  27  *
  28  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  29  * @version 1
  30  */
  31 package jexer.bits;
  32
  33 /**
  34  * MnemonicString is used to render a string like "&File" into a highlighted
  35  * 'F' and the rest of 'ile'.  To insert a literal '&', use two '&&'
  36  * characters, e.g. "&File && Stuff" would be "File & Stuff" with the first
  37  * 'F' highlighted.
  38  */
  39 public class MnemonicString {
  40
  41     /**
  42      * Keyboard shortcut to activate this item.
  43      */
  44     private char shortcut;
  45
  46     /**
  47      * Location of the highlighted character.
  48      */
  49     private int shortcutIdx = -1;
  50
  51     /**
  52      * The raw (uncolored) string.
  53      */
  54     private String rawLabel;
  55
  56     /**
  57      * Public constructor.
  58      *
  59      * @param label widget label or title.  Label must contain a keyboard
  60      * shortcut, denoted by prefixing a letter with "&", e.g. "&File"
  61      */
  62     public MnemonicString(final String label) {
  63
  64         // Setup the menu shortcut
  65         String newLabel = "";
  66         boolean foundAmp = false;
  67         boolean foundShortcut = false;
  68         int scanShortcutIdx = 0;
  69         for (int i = 0; i < label.length(); i++) {
  70             char c = label.charAt(i);
  71             if (c == '&') {
  72                 if (foundAmp) {
  73                     newLabel += '&';
  74                     scanShortcutIdx++;
  75                 } else {
  76                     foundAmp = true;
  77                 }
  78             } else {
  79                 newLabel += c;
  80                 if (foundAmp) {
  81                     if (!foundShortcut) {
  82                         shortcut = c;
  83                         foundAmp = false;
  84                         foundShortcut = true;
  85                         shortcutIdx = scanShortcutIdx;
  86                     }
  87                 } else {
  88                     scanShortcutIdx++;
  89                 }
  90             }
  91         }
  92         this.rawLabel = newLabel;
  93     }
  94 }