src/jexer/TButton.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2017 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.Color;
  33 import jexer.bits.GraphicsChars;
  34 import jexer.bits.MnemonicString;
  35 import jexer.event.TKeypressEvent;
  36 import jexer.event.TMouseEvent;
  37 import static jexer.TKeypress.*;
  38
  39 /**
  40  * TButton implements a simple button.  To make the button do something, pass
  41  * a TAction class to its constructor.
  42  *
  43  * @see TAction#DO()
  44  */
  45 public final class TButton extends TWidget {
  46
  47     /**
  48      * The shortcut and button text.
  49      */
  50     private MnemonicString mnemonic;
  51
  52     /**
  53      * Get the mnemonic string for this button.
  54      *
  55      * @return mnemonic string
  56      */
  57     public MnemonicString getMnemonic() {
  58         return mnemonic;
  59     }
  60
  61     /**
  62      * Remember mouse state.
  63      */
  64     private TMouseEvent mouse;
  65
  66     /**
  67      * True when the button is being pressed and held down.
  68      */
  69     private boolean inButtonPress = false;
  70
  71     /**
  72      * The action to perform when the button is clicked.
  73      */
  74     private TAction action;
  75
  76     /**
  77      * How long to animate dispatch of the event in millis.
  78      */
  79     private static final long DISPATCH_TIME = 75;
  80
  81     /**
  82      * Act as though the button was pressed.  This is useful for other UI
  83      * elements to get the same action as if the user clicked the button.
  84      */
  85     public void dispatch() {
  86         if (action != null) {
  87             action.DO();
  88             inButtonPress = false;
  89         }
  90     }
  91
  92     /**
  93      * Private constructor.
  94      *
  95      * @param parent parent widget
  96      * @param text label on the button
  97      * @param x column relative to parent
  98      * @param y row relative to parent
  99      */
 100     private TButton(final TWidget parent, final String text,
 101         final int x, final int y) {
 102
 103         // Set parent and window
 104         super(parent);
 105
 106         mnemonic = new MnemonicString(text);
 107
 108         setX(x);
 109         setY(y);
 110         setHeight(2);
 111         setWidth(mnemonic.getRawLabel().length() + 3);
 112     }
 113
 114     /**
 115      * Public constructor.
 116      *
 117      * @param parent parent widget
 118      * @param text label on the button
 119      * @param x column relative to parent
 120      * @param y row relative to parent
 121      * @param action to call when button is pressed
 122      */
 123     public TButton(final TWidget parent, final String text,
 124         final int x, final int y, final TAction action) {
 125
 126         this(parent, text, x, y);
 127         this.action = action;
 128     }
 129
 130     /**
 131      * Returns true if the mouse is currently on the button.
 132      *
 133      * @return if true the mouse is currently on the button
 134      */
 135     private boolean mouseOnButton() {
 136         int rightEdge = getWidth() - 1;
 137         if (inButtonPress) {
 138             rightEdge++;
 139         }
 140         if ((mouse != null)
 141             && (mouse.getY() == 0)
 142             && (mouse.getX() >= 0)
 143             && (mouse.getX() < rightEdge)
 144         ) {
 145             return true;
 146         }
 147         return false;
 148     }
 149
 150     /**
 151      * Draw a button with a shadow.
 152      */
 153     @Override
 154     public void draw() {
 155         CellAttributes buttonColor;
 156         CellAttributes menuMnemonicColor;
 157         CellAttributes shadowColor = new CellAttributes();
 158         shadowColor.setTo(getWindow().getBackground());
 159         shadowColor.setForeColor(Color.BLACK);
 160         shadowColor.setBold(false);
 161
 162         if (!isEnabled()) {
 163             buttonColor = getTheme().getColor("tbutton.disabled");
 164             menuMnemonicColor = getTheme().getColor("tbutton.disabled");
 165         } else if (isAbsoluteActive()) {
 166             buttonColor = getTheme().getColor("tbutton.active");
 167             menuMnemonicColor = getTheme().getColor("tbutton.mnemonic.highlighted");
 168         } else {
 169             buttonColor = getTheme().getColor("tbutton.inactive");
 170             menuMnemonicColor = getTheme().getColor("tbutton.mnemonic");
 171         }
 172
 173         if (inButtonPress) {
 174             getScreen().putCharXY(1, 0, ' ', buttonColor);
 175             getScreen().putStringXY(2, 0, mnemonic.getRawLabel(), buttonColor);
 176             getScreen().putCharXY(getWidth() - 1, 0, ' ', buttonColor);
 177         } else {
 178             getScreen().putCharXY(0, 0, ' ', buttonColor);
 179             getScreen().putStringXY(1, 0, mnemonic.getRawLabel(), buttonColor);
 180             getScreen().putCharXY(getWidth() - 2, 0, ' ', buttonColor);
 181
 182             getScreen().putCharXY(getWidth() - 1, 0,
 183                 GraphicsChars.CP437[0xDC], shadowColor);
 184             getScreen().hLineXY(1, 1, getWidth() - 1,
 185                 GraphicsChars.CP437[0xDF], shadowColor);
 186         }
 187         if (mnemonic.getShortcutIdx() >= 0) {
 188             if (inButtonPress) {
 189                 getScreen().putCharXY(2 + mnemonic.getShortcutIdx(), 0,
 190                     mnemonic.getShortcut(), menuMnemonicColor);
 191             } else {
 192                 getScreen().putCharXY(1 + mnemonic.getShortcutIdx(), 0,
 193                     mnemonic.getShortcut(), menuMnemonicColor);
 194             }
 195
 196         }
 197     }
 198
 199     /**
 200      * Handle mouse button presses.
 201      *
 202      * @param mouse mouse button event
 203      */
 204     @Override
 205     public void onMouseDown(final TMouseEvent mouse) {
 206         this.mouse = mouse;
 207
 208         if ((mouseOnButton()) && (mouse.isMouse1())) {
 209             // Begin button press
 210             inButtonPress = true;
 211         }
 212     }
 213
 214     /**
 215      * Handle mouse button releases.
 216      *
 217      * @param mouse mouse button release event
 218      */
 219     @Override
 220     public void onMouseUp(final TMouseEvent mouse) {
 221         this.mouse = mouse;
 222
 223         if (inButtonPress && mouse.isMouse1()) {
 224             // Dispatch the event
 225             dispatch();
 226         }
 227
 228     }
 229
 230     /**
 231      * Handle mouse movements.
 232      *
 233      * @param mouse mouse motion event
 234      */
 235     @Override
 236     public void onMouseMotion(final TMouseEvent mouse) {
 237         this.mouse = mouse;
 238
 239         if (!mouseOnButton()) {
 240             inButtonPress = false;
 241         }
 242     }
 243
 244     /**
 245      * Handle keystrokes.
 246      *
 247      * @param keypress keystroke event
 248      */
 249     @Override
 250     public void onKeypress(final TKeypressEvent keypress) {
 251         if (keypress.equals(kbEnter)
 252             || keypress.equals(kbSpace)
 253         ) {
 254             // Dispatch
 255             dispatch();
 256             return;
 257         }
 258
 259         // Pass to parent for the things we don't care about.
 260         super.onKeypress(keypress);
 261     }
 262
 263 }