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         if (menu.isActive()) {
 104             menu.onKeypress(keypress);
 105             return;
 106         }
 107
 108         if (keypress.equals(kbEnter)) {
 109             dispatch();
 110             return;
 111         }
 112
 113         if (keypress.equals(kbRight)) {
 114             dispatch();
 115             return;
 116         }
 117
 118         if (keypress.equals(kbDown)) {
 119             getParent().switchWidget(true);
 120             return;
 121         }
 122
 123         if (keypress.equals(kbUp)) {
 124             getParent().switchWidget(false);
 125             return;
 126         }
 127
 128         if (keypress.equals(kbLeft)) {
 129             TMenu parentMenu = (TMenu) getParent();
 130             if (parentMenu.isSubMenu) {
 131                 getApplication().closeSubMenu();
 132             } else {
 133                 getApplication().switchMenu(false);
 134             }
 135             return;
 136         }
 137
 138         if (keypress.equals(kbEsc)) {
 139             getApplication().closeMenu();
 140             return;
 141         }
 142     }
 143
 144     /**
 145      * Override dispatch() to do nothing.
 146      */
 147     @Override
 148     public void dispatch() {
 149         assert (isEnabled());
 150         if (isAbsoluteActive()) {
 151             if (!menu.isActive()) {
 152                 getApplication().addSubMenu(menu);
 153                 menu.setActive(true);
 154             }
 155         }
 156     }
 157
 158     /**
 159      * Returns my active widget.
 160      *
 161      * @return widget that is active, or this if no children
 162      */
 163     @Override
 164     public TWidget getActiveChild() {
 165         if (menu.isActive()) {
 166             return menu;
 167         }
 168         // Menu not active, return me
 169         return this;
 170     }
 171
 172     /**
 173      * Convenience function to add a custom menu item.
 174      *
 175      * @param id menu item ID.  Must be greater than 1024.
 176      * @param label menu item label
 177      * @param key global keyboard accelerator
 178      * @return the new menu item
 179      */
 180     public TMenuItem addItem(final int id, final String label,
 181         final TKeypress key) {
 182
 183         return menu.addItem(id, label, key);
 184     }
 185
 186     /**
 187      * Convenience function to add a menu item.
 188      *
 189      * @param id menu item ID.  Must be greater than 1024.
 190      * @param label menu item label
 191      * @return the new menu item
 192      */
 193     public TMenuItem addItem(final int id, final String label) {
 194         return menu.addItem(id, label);
 195     }
 196
 197     /**
 198      * Convenience function to add one of the default menu items.
 199      *
 200      * @param id menu item ID.  Must be between 0 (inclusive) and 1023
 201      * (inclusive).
 202      * @return the new menu item
 203      */
 204     public TMenuItem addDefaultItem(final int id) {
 205         return menu.addDefaultItem(id);
 206     }
 207
 208     /**
 209      * Convenience function to add a menu separator.
 210      */
 211     public void addSeparator() {
 212         menu.addSeparator();
 213     }
 214
 215     /**
 216      * Convenience function to add a sub-menu.
 217      *
 218      * @param title menu title.  Title must contain a keyboard shortcut,
 219      * denoted by prefixing a letter with "&", e.g. "&File"
 220      * @return the new sub-menu
 221      */
 222     public TSubMenu addSubMenu(final String title) {
 223         return menu.addSubMenu(title);
 224     }
 225
 226
 227 }