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.bits.StringUtils;
  35 import jexer.event.TKeypressEvent;
  36 import jexer.event.TMouseEvent;
  37 import static jexer.TKeypress.*;
  38
  39 /**
  40  * TRadioButton implements a selectable radio button.
  41  *
  42  * If the user clicks or presses space on this button, it is selected.
  43  *
  44  * If the user presses escape on this button, it is unselected.
  45  */
  46 public class TRadioButton extends TWidget {
  47
  48     // ------------------------------------------------------------------------
  49     // Variables --------------------------------------------------------------
  50     // ------------------------------------------------------------------------
  51
  52     /**
  53      * RadioButton state, true means selected.  Note package private access.
  54      */
  55     boolean selected = false;
  56
  57     /**
  58      * The shortcut and radio button label.
  59      */
  60     private MnemonicString mnemonic;
  61
  62     /**
  63      * ID for this radio button.  Buttons start counting at 1 in the
  64      * RadioGroup.  Note package private access.
  65      */
  66     int id;
  67
  68     // ------------------------------------------------------------------------
  69     // Constructors -----------------------------------------------------------
  70     // ------------------------------------------------------------------------
  71
  72     /**
  73      * Package private constructor.
  74      *
  75      * @param parent parent widget
  76      * @param x column relative to parent
  77      * @param y row relative to parent
  78      * @param label label to display next to (right of) the radiobutton
  79      * @param id ID for this radio button
  80      */
  81     TRadioButton(final TRadioGroup parent, final int x, final int y,
  82         final String label, final int id) {
  83
  84         // Set parent and window
  85         super(parent, x, y, StringUtils.width(label) + 4, 1);
  86
  87         mnemonic = new MnemonicString(label);
  88         this.id = id;
  89
  90         setCursorVisible(true);
  91         setCursorX(1);
  92
  93         parent.addRadioButton(this);
  94     }
  95
  96     // ------------------------------------------------------------------------
  97     // Event handlers ---------------------------------------------------------
  98     // ------------------------------------------------------------------------
  99
 100     /**
 101      * Returns true if the mouse is currently on the radio button.
 102      *
 103      * @param mouse mouse event
 104      * @return if true the mouse is currently on the radio button
 105      */
 106     private boolean mouseOnRadioButton(final TMouseEvent mouse) {
 107         if ((mouse.getY() == 0)
 108             && (mouse.getX() >= 0)
 109             && (mouse.getX() <= 2)
 110         ) {
 111             return true;
 112         }
 113         return false;
 114     }
 115
 116     /**
 117      * Handle mouse button presses.
 118      *
 119      * @param mouse mouse button press event
 120      */
 121     @Override
 122     public void onMouseDown(final TMouseEvent mouse) {
 123         if ((mouseOnRadioButton(mouse)) && (mouse.isMouse1())) {
 124             // Switch state
 125             ((TRadioGroup) getParent()).setSelected(id);
 126         }
 127     }
 128
 129     /**
 130      * Handle keystrokes.
 131      *
 132      * @param keypress keystroke event
 133      */
 134     @Override
 135     public void onKeypress(final TKeypressEvent keypress) {
 136
 137         if (keypress.equals(kbSpace)) {
 138             ((TRadioGroup) getParent()).setSelected(id);
 139             return;
 140         }
 141
 142         if (keypress.equals(kbEsc)) {
 143             TRadioGroup parent = (TRadioGroup) getParent();
 144             if (parent.requiresSelection == false) {
 145                 selected = false;
 146                 parent.setSelected(0);
 147             }
 148             return;
 149         }
 150
 151         // Pass to parent for the things we don't care about.
 152         super.onKeypress(keypress);
 153     }
 154
 155     // ------------------------------------------------------------------------
 156     // TWidget ----------------------------------------------------------------
 157     // ------------------------------------------------------------------------
 158
 159     /**
 160      * Override TWidget's width: we can only set width at construction time.
 161      *
 162      * @param width new widget width (ignored)
 163      */
 164     @Override
 165     public void setWidth(final int width) {
 166         // Do nothing
 167     }
 168
 169     /**
 170      * Override TWidget's height: we can only set height at construction
 171      * time.
 172      *
 173      * @param height new widget height (ignored)
 174      */
 175     @Override
 176     public void setHeight(final int height) {
 177         // Do nothing
 178     }
 179
 180     /**
 181      * Draw a radio button with label.
 182      */
 183     @Override
 184     public void draw() {
 185         CellAttributes radioButtonColor;
 186         CellAttributes mnemonicColor;
 187
 188         if (isAbsoluteActive()) {
 189             radioButtonColor = getTheme().getColor("tradiobutton.active");
 190             mnemonicColor = getTheme().getColor("tradiobutton.mnemonic.highlighted");
 191         } else {
 192             radioButtonColor = getTheme().getColor("tradiobutton.inactive");
 193             mnemonicColor = getTheme().getColor("tradiobutton.mnemonic");
 194         }
 195
 196         putCharXY(0, 0, '(', radioButtonColor);
 197         if (selected) {
 198             putCharXY(1, 0, GraphicsChars.CP437[0x07], radioButtonColor);
 199         } else {
 200             putCharXY(1, 0, ' ', radioButtonColor);
 201         }
 202         putCharXY(2, 0, ')', radioButtonColor);
 203         putStringXY(4, 0, mnemonic.getRawLabel(), radioButtonColor);
 204         if (mnemonic.getScreenShortcutIdx() >= 0) {
 205             putCharXY(4 + mnemonic.getScreenShortcutIdx(), 0,
 206                 mnemonic.getShortcut(), mnemonicColor);
 207         }
 208     }
 209
 210     // ------------------------------------------------------------------------
 211     // TRadioButton -----------------------------------------------------------
 212     // ------------------------------------------------------------------------
 213
 214     /**
 215      * Get RadioButton state, true means selected.
 216      *
 217      * @return if true then this is the one button in the group that is
 218      * selected
 219      */
 220     public boolean isSelected() {
 221         return selected;
 222     }
 223
 224     /**
 225      * Set RadioButton state, true means selected.
 226      *
 227      * @param selected if true then this is the one button in the group that
 228      * is selected
 229      */
 230     public void setSelected(final boolean selected) {
 231         if (selected == true) {
 232             ((TRadioGroup) getParent()).setSelected(id);
 233         } else {
 234             ((TRadioGroup) getParent()).setSelected(0);
 235         }
 236     }
 237
 238     /**
 239      * Get ID for this radio button.  Buttons start counting at 1 in the
 240      * RadioGroup.
 241      *
 242      * @return the ID
 243      */
 244     public int getId() {
 245         return id;
 246     }
 247
 248     /**
 249      * Get the mnemonic string for this button.
 250      *
 251      * @return mnemonic string
 252      */
 253     public MnemonicString getMnemonic() {
 254         return mnemonic;
 255     }
 256
 257 }