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.TWidget;
  34 import jexer.bits.CellAttributes;
  35 import jexer.bits.GraphicsChars;
  36 import jexer.event.TKeypressEvent;
  37 import static jexer.TKeypress.*;
  38
  39 /**
  40  * TSubMenu is a special case menu item that wraps another TMenu.
  41  */
  42 public class TSubMenu extends TMenuItem {
  43
  44     /**
  45      * The menu window.  Note package private access.
  46      */
  47     TMenu menu;
  48
  49     /**
  50      * Package private constructor.
  51      *
  52      * @param parent parent widget
  53      * @param title menu title.  Title must contain a keyboard shortcut,
  54      * denoted by prefixing a letter with "&", e.g. "&File"
  55      * @param x column relative to parent
  56      * @param y row relative to parent
  57      */
  58     TSubMenu(final TMenu parent, final String title, final int x, final int y) {
  59         super(parent, TMenu.MID_UNUSED, x, y, title);
  60
  61         setActive(false);
  62         setEnabled(true);
  63
  64         this.menu = new TMenu(parent.getApplication(), x, getAbsoluteY() - 1,
  65             title);
  66         setWidth(menu.getWidth() + 2);
  67
  68         this.menu.isSubMenu = true;
  69     }
  70
  71     /**
  72      * Draw the menu title.
  73      */
  74     @Override
  75     public void draw() {
  76         super.draw();
  77
  78         CellAttributes background = getTheme().getColor("tmenu");
  79         CellAttributes menuColor;
  80         CellAttributes menuMnemonicColor;
  81         if (getAbsoluteActive()) {
  82             menuColor = getTheme().getColor("tmenu.highlighted");
  83             menuMnemonicColor = getTheme().getColor("tmenu.mnemonic.highlighted");
  84         } else {
  85             if (getEnabled()) {
  86                 menuColor = getTheme().getColor("tmenu");
  87                 menuMnemonicColor = getTheme().getColor("tmenu.mnemonic");
  88             } else {
  89                 menuColor = getTheme().getColor("tmenu.disabled");
  90                 menuMnemonicColor = getTheme().getColor("tmenu.disabled");
  91             }
  92         }
  93
  94         // Add the arrow
  95         getScreen().putCharXY(getWidth() - 2, 0, GraphicsChars.CP437[0x10],
  96             menuColor);
  97     }
  98
  99     /**
 100      * Handle keystrokes.
 101      *
 102      * @param keypress keystroke event
 103      */
 104     @Override
 105     public void onKeypress(final TKeypressEvent keypress) {
 106
 107         if (menu.getActive()) {
 108             menu.onKeypress(keypress);
 109             return;
 110         }
 111
 112         if (keypress.equals(kbEnter)) {
 113             dispatch();
 114             return;
 115         }
 116
 117         if (keypress.equals(kbRight)) {
 118             dispatch();
 119             return;
 120         }
 121
 122         if (keypress.equals(kbDown)) {
 123             getParent().switchWidget(true);
 124             return;
 125         }
 126
 127         if (keypress.equals(kbUp)) {
 128             getParent().switchWidget(false);
 129             return;
 130         }
 131
 132         if (keypress.equals(kbLeft)) {
 133             TMenu parentMenu = (TMenu) getParent();
 134             if (parentMenu.isSubMenu) {
 135                 getApplication().closeSubMenu();
 136             } else {
 137                 getApplication().switchMenu(false);
 138             }
 139             return;
 140         }
 141
 142         if (keypress.equals(kbEsc)) {
 143             getApplication().closeMenu();
 144             return;
 145         }
 146     }
 147
 148     /**
 149      * Override dispatch() to do nothing.
 150      */
 151     @Override
 152     public void dispatch() {
 153         assert (getEnabled());
 154         if (getAbsoluteActive()) {
 155             if (!menu.getActive()) {
 156                 getApplication().addSubMenu(menu);
 157                 menu.setActive(true);
 158             }
 159         }
 160     }
 161
 162     /**
 163      * Returns my active widget.
 164      *
 165      * @return widget that is active, or this if no children
 166      */
 167     @Override
 168     public TWidget getActiveChild() {
 169         if (menu.getActive()) {
 170             return menu;
 171         }
 172         // Menu not active, return me
 173         return this;
 174     }
 175
 176 }