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 background = getTheme().getColor("tmenu");
  80         CellAttributes menuColor;
  81         CellAttributes menuMnemonicColor;
  82         if (getAbsoluteActive()) {
  83             menuColor = getTheme().getColor("tmenu.highlighted");
  84             menuMnemonicColor = getTheme().getColor("tmenu.mnemonic.highlighted");
  85         } else {
  86             if (getEnabled()) {
  87                 menuColor = getTheme().getColor("tmenu");
  88                 menuMnemonicColor = getTheme().getColor("tmenu.mnemonic");
  89             } else {
  90                 menuColor = getTheme().getColor("tmenu.disabled");
  91                 menuMnemonicColor = getTheme().getColor("tmenu.disabled");
  92             }
  93         }
  94
  95         // Add the arrow
  96         getScreen().putCharXY(getWidth() - 2, 0, GraphicsChars.CP437[0x10],
  97             menuColor);
  98     }
  99
 100     /**
 101      * Handle keystrokes.
 102      *
 103      * @param keypress keystroke event
 104      */
 105     @Override
 106     public void onKeypress(final TKeypressEvent keypress) {
 107
 108         if (menu.getActive()) {
 109             menu.onKeypress(keypress);
 110             return;
 111         }
 112
 113         if (keypress.equals(kbEnter)) {
 114             dispatch();
 115             return;
 116         }
 117
 118         if (keypress.equals(kbRight)) {
 119             dispatch();
 120             return;
 121         }
 122
 123         if (keypress.equals(kbDown)) {
 124             getParent().switchWidget(true);
 125             return;
 126         }
 127
 128         if (keypress.equals(kbUp)) {
 129             getParent().switchWidget(false);
 130             return;
 131         }
 132
 133         if (keypress.equals(kbLeft)) {
 134             TMenu parentMenu = (TMenu) getParent();
 135             if (parentMenu.isSubMenu) {
 136                 getApplication().closeSubMenu();
 137             } else {
 138                 getApplication().switchMenu(false);
 139             }
 140             return;
 141         }
 142
 143         if (keypress.equals(kbEsc)) {
 144             getApplication().closeMenu();
 145             return;
 146         }
 147     }
 148
 149     /**
 150      * Override dispatch() to do nothing.
 151      */
 152     @Override
 153     public void dispatch() {
 154         assert (getEnabled());
 155         if (getAbsoluteActive()) {
 156             if (!menu.getActive()) {
 157                 getApplication().addSubMenu(menu);
 158                 menu.setActive(true);
 159             }
 160         }
 161     }
 162
 163     /**
 164      * Returns my active widget.
 165      *
 166      * @return widget that is active, or this if no children
 167      */
 168     @Override
 169     public TWidget getActiveChild() {
 170         if (menu.getActive()) {
 171             return menu;
 172         }
 173         // Menu not active, return me
 174         return this;
 175     }
 176
 177     /**
 178      * Convenience function to add a custom menu item.
 179      *
 180      * @param id menu item ID.  Must be greater than 1024.
 181      * @param label menu item label
 182      * @param key global keyboard accelerator
 183      * @return the new menu item
 184      */
 185     public TMenuItem addItem(final int id, final String label,
 186         final TKeypress key) {
 187
 188         return menu.addItem(id, label, key);
 189     }
 190
 191     /**
 192      * Convenience function to add a menu item.
 193      *
 194      * @param id menu item ID.  Must be greater than 1024.
 195      * @param label menu item label
 196      * @return the new menu item
 197      */
 198     public TMenuItem addItem(final int id, final String label) {
 199         return menu.addItem(id, label);
 200     }
 201
 202     /**
 203      * Convenience function to add one of the default menu items.
 204      *
 205      * @param id menu item ID.  Must be between 0 (inclusive) and 1023
 206      * (inclusive).
 207      * @return the new menu item
 208      */
 209     public TMenuItem addDefaultItem(final int id) {
 210         return menu.addDefaultItem(id);
 211     }
 212
 213     /**
 214      * Convenience function to add a menu separator.
 215      */
 216     public void addSeparator() {
 217         menu.addSeparator();
 218     }
 219
 220     /**
 221      * Convenience function to add a sub-menu.
 222      *
 223      * @param title menu title.  Title must contain a keyboard shortcut,
 224      * denoted by prefixing a letter with "&", e.g. "&File"
 225      * @return the new sub-menu
 226      */
 227     public TSubMenu addSubMenu(final String title) {
 228         return menu.addSubMenu(title);
 229     }
 230
 231
 232 }