src/jexer/menu/TSubMenu.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.menu;
  32
  33 import jexer.TKeypress;
  34 import jexer.TWidget;
  35 import jexer.bits.CellAttributes;
  36 import jexer.bits.GraphicsChars;
  37 import jexer.event.TKeypressEvent;
  38 import static jexer.TKeypress.*;
  39
  40 /**
  41  * TSubMenu is a special case menu item that wraps another TMenu.
  42  */
  43 public final class TSubMenu extends TMenuItem {
  44
  45     /**
  46      * The menu window.  Note package private access.
  47      */
  48     TMenu menu;
  49
  50     /**
  51      * Package private constructor.
  52      *
  53      * @param parent parent widget
  54      * @param title menu title.  Title must contain a keyboard shortcut,
  55      * denoted by prefixing a letter with "&", e.g. "&File"
  56      * @param x column relative to parent
  57      * @param y row relative to parent
  58      */
  59     TSubMenu(final TMenu parent, final String title, final int x, final int y) {
  60         super(parent, TMenu.MID_UNUSED, x, y, title);
  61
  62         setActive(false);
  63         setEnabled(true);
  64
  65         this.menu = new TMenu(parent.getApplication(), x, getAbsoluteY() - 1,
  66             title);
  67         setWidth(menu.getWidth() + 2);
  68
  69         this.menu.isSubMenu = true;
  70     }
  71
  72     /**
  73      * Draw the menu title.
  74      */
  75     @Override
  76     public void draw() {
  77         super.draw();
  78
  79         CellAttributes menuColor;
  80         if (isAbsoluteActive()) {
  81             menuColor = getTheme().getColor("tmenu.highlighted");
  82         } else {
  83             if (isEnabled()) {
  84                 menuColor = getTheme().getColor("tmenu");
  85             } else {
  86                 menuColor = getTheme().getColor("tmenu.disabled");
  87             }
  88         }
  89
  90         // Add the arrow
  91         getScreen().putCharXY(getWidth() - 2, 0, GraphicsChars.CP437[0x10],
  92             menuColor);
  93     }
  94
  95     /**
  96      * Handle keystrokes.
  97      *
  98      * @param keypress keystroke event
  99      */
 100     @Override
 101     public void onKeypress(final TKeypressEvent keypress) {
 102
 103         // Open me if they hit my mnemonic.
 104         if (!keypress.getKey().isFnKey()
 105             && !keypress.getKey().isAlt()
 106             && !keypress.getKey().isCtrl()
 107             && (getMnemonic() != null)
 108             && (Character.toLowerCase(getMnemonic().getShortcut())
 109                 == Character.toLowerCase(keypress.getKey().getChar()))
 110         ) {
 111             dispatch();
 112             return;
 113         }
 114
 115         if (menu.isActive()) {
 116             menu.onKeypress(keypress);
 117             return;
 118         }
 119
 120         if (keypress.equals(kbEnter)) {
 121             dispatch();
 122             return;
 123         }
 124
 125         if (keypress.equals(kbRight)) {
 126             dispatch();
 127             return;
 128         }
 129
 130         if (keypress.equals(kbDown)) {
 131             getParent().switchWidget(true);
 132             return;
 133         }
 134
 135         if (keypress.equals(kbUp)) {
 136             getParent().switchWidget(false);
 137             return;
 138         }
 139
 140         if (keypress.equals(kbLeft)) {
 141             TMenu parentMenu = (TMenu) getParent();
 142             if (parentMenu.isSubMenu) {
 143                 getApplication().closeSubMenu();
 144             } else {
 145                 getApplication().switchMenu(false);
 146             }
 147             return;
 148         }
 149
 150         if (keypress.equals(kbEsc)) {
 151             getApplication().closeMenu();
 152             return;
 153         }
 154     }
 155
 156     /**
 157      * Override dispatch() to do nothing.
 158      */
 159     @Override
 160     public void dispatch() {
 161         assert (isEnabled());
 162         if (isAbsoluteActive()) {
 163             if (!menu.isActive()) {
 164                 getApplication().addSubMenu(menu);
 165                 menu.setActive(true);
 166             }
 167         }
 168     }
 169
 170     /**
 171      * Returns my active widget.
 172      *
 173      * @return widget that is active, or this if no children
 174      */
 175     @Override
 176     public TWidget getActiveChild() {
 177         if (menu.isActive()) {
 178             return menu;
 179         }
 180         // Menu not active, return me
 181         return this;
 182     }
 183
 184     /**
 185      * Convenience function to add a custom menu item.
 186      *
 187      * @param id menu item ID.  Must be greater than 1024.
 188      * @param label menu item label
 189      * @param key global keyboard accelerator
 190      * @return the new menu item
 191      */
 192     public TMenuItem addItem(final int id, final String label,
 193         final TKeypress key) {
 194
 195         return menu.addItem(id, label, key);
 196     }
 197
 198     /**
 199      * Convenience function to add a menu item.
 200      *
 201      * @param id menu item ID.  Must be greater than 1024.
 202      * @param label menu item label
 203      * @return the new menu item
 204      */
 205     public TMenuItem addItem(final int id, final String label) {
 206         return menu.addItem(id, label);
 207     }
 208
 209     /**
 210      * Convenience function to add one of the default menu items.
 211      *
 212      * @param id menu item ID.  Must be between 0 (inclusive) and 1023
 213      * (inclusive).
 214      * @return the new menu item
 215      */
 216     public TMenuItem addDefaultItem(final int id) {
 217         return menu.addDefaultItem(id);
 218     }
 219
 220     /**
 221      * Convenience function to add a menu separator.
 222      */
 223     public void addSeparator() {
 224         menu.addSeparator();
 225     }
 226
 227     /**
 228      * Convenience function to add a sub-menu.
 229      *
 230      * @param title menu title.  Title must contain a keyboard shortcut,
 231      * denoted by prefixing a letter with "&", e.g. "&File"
 232      * @return the new sub-menu
 233      */
 234     public TSubMenu addSubMenu(final String title) {
 235         return menu.addSubMenu(title);
 236     }
 237
 238
 239 }