src/jexer/TRadioButton.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2019 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer;
  30
  31 import jexer.bits.CellAttributes;
  32 import jexer.bits.GraphicsChars;
  33 import jexer.bits.MnemonicString;
  34 import jexer.event.TKeypressEvent;
  35 import jexer.event.TMouseEvent;
  36 import static jexer.TKeypress.*;
  37
  38 /**
  39  * TRadioButton implements a selectable radio button.
  40  *
  41  * If the user clicks or presses space on this button, it is selected.
  42  *
  43  * If the user presses escape on this button, it is unselected.
  44  */
  45 public class TRadioButton extends TWidget {
  46
  47     // ------------------------------------------------------------------------
  48     // Variables --------------------------------------------------------------
  49     // ------------------------------------------------------------------------
  50
  51     /**
  52      * RadioButton state, true means selected.
  53      */
  54     private boolean selected = false;
  55
  56     /**
  57      * The shortcut and radio button label.
  58      */
  59     private MnemonicString mnemonic;
  60
  61     /**
  62      * ID for this radio button.  Buttons start counting at 1 in the
  63      * RadioGroup.
  64      */
  65     private int id;
  66
  67     // ------------------------------------------------------------------------
  68     // Constructors -----------------------------------------------------------
  69     // ------------------------------------------------------------------------
  70
  71     /**
  72      * Public constructor.
  73      *
  74      * @param parent parent widget
  75      * @param x column relative to parent
  76      * @param y row relative to parent
  77      * @param label label to display next to (right of) the radiobutton
  78      * @param id ID for this radio button
  79      */
  80     public TRadioButton(final TRadioGroup parent, final int x, final int y,
  81         final String label, final int id) {
  82
  83         // Set parent and window
  84         super(parent, x, y, label.length() + 4, 1);
  85
  86         mnemonic = new MnemonicString(label);
  87         this.id = id;
  88
  89         setCursorVisible(true);
  90         setCursorX(1);
  91     }
  92
  93     // ------------------------------------------------------------------------
  94     // Event handlers ---------------------------------------------------------
  95     // ------------------------------------------------------------------------
  96
  97     /**
  98      * Returns true if the mouse is currently on the radio button.
  99      *
 100      * @param mouse mouse event
 101      * @return if true the mouse is currently on the radio button
 102      */
 103     private boolean mouseOnRadioButton(final TMouseEvent mouse) {
 104         if ((mouse.getY() == 0)
 105             && (mouse.getX() >= 0)
 106             && (mouse.getX() <= 2)
 107         ) {
 108             return true;
 109         }
 110         return false;
 111     }
 112
 113     /**
 114      * Handle mouse button presses.
 115      *
 116      * @param mouse mouse button press event
 117      */
 118     @Override
 119     public void onMouseDown(final TMouseEvent mouse) {
 120         if ((mouseOnRadioButton(mouse)) && (mouse.isMouse1())) {
 121             // Switch state
 122             selected = true;
 123             ((TRadioGroup) getParent()).setSelected(this);
 124         }
 125     }
 126
 127     /**
 128      * Handle keystrokes.
 129      *
 130      * @param keypress keystroke event
 131      */
 132     @Override
 133     public void onKeypress(final TKeypressEvent keypress) {
 134
 135         if (keypress.equals(kbSpace)) {
 136             selected = true;
 137             ((TRadioGroup) getParent()).setSelected(this);
 138             return;
 139         }
 140
 141         if (keypress.equals(kbEsc)) {
 142             TRadioGroup parent = (TRadioGroup) getParent();
 143             if (parent.requiresSelection == false) {
 144                 selected = false;
 145                 parent.setSelected(0);
 146             }
 147             return;
 148         }
 149
 150         // Pass to parent for the things we don't care about.
 151         super.onKeypress(keypress);
 152     }
 153
 154     // ------------------------------------------------------------------------
 155     // TWidget ----------------------------------------------------------------
 156     // ------------------------------------------------------------------------
 157
 158     /**
 159      * Draw a radio button with label.
 160      */
 161     @Override
 162     public void draw() {
 163         CellAttributes radioButtonColor;
 164         CellAttributes mnemonicColor;
 165
 166         if (isAbsoluteActive()) {
 167             radioButtonColor = getTheme().getColor("tradiobutton.active");
 168             mnemonicColor = getTheme().getColor("tradiobutton.mnemonic.highlighted");
 169         } else {
 170             radioButtonColor = getTheme().getColor("tradiobutton.inactive");
 171             mnemonicColor = getTheme().getColor("tradiobutton.mnemonic");
 172         }
 173
 174         putCharXY(0, 0, '(', radioButtonColor);
 175         if (selected) {
 176             putCharXY(1, 0, GraphicsChars.CP437[0x07], radioButtonColor);
 177         } else {
 178             putCharXY(1, 0, ' ', radioButtonColor);
 179         }
 180         putCharXY(2, 0, ')', radioButtonColor);
 181         putStringXY(4, 0, mnemonic.getRawLabel(), radioButtonColor);
 182         if (mnemonic.getShortcutIdx() >= 0) {
 183             putCharXY(4 + mnemonic.getShortcutIdx(), 0,
 184                 mnemonic.getShortcut(), mnemonicColor);
 185         }
 186     }
 187
 188     // ------------------------------------------------------------------------
 189     // TRadioButton -----------------------------------------------------------
 190     // ------------------------------------------------------------------------
 191
 192     /**
 193      * Get RadioButton state, true means selected.
 194      *
 195      * @return if true then this is the one button in the group that is
 196      * selected
 197      */
 198     public boolean isSelected() {
 199         return selected;
 200     }
 201
 202     /**
 203      * Set RadioButton state, true means selected.  Note package private
 204      * access.
 205      *
 206      * @param selected if true then this is the one button in the group that
 207      * is selected
 208      */
 209     void setSelected(final boolean selected) {
 210         this.selected = selected;
 211     }
 212
 213     /**
 214      * Get ID for this radio button.  Buttons start counting at 1 in the
 215      * RadioGroup.
 216      *
 217      * @return the ID
 218      */
 219     public int getId() {
 220         return id;
 221     }
 222
 223     /**
 224      * Get the mnemonic string for this button.
 225      *
 226      * @return mnemonic string
 227      */
 228     public MnemonicString getMnemonic() {
 229         return mnemonic;
 230     }
 231
 232 }