src/jexer/TMessageBox.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;
  32
  33 import java.util.ArrayList;
  34 import java.util.List;
  35
  36 /**
  37  * TMessageBox is a system-modal dialog with buttons for OK, Cancel, Yes, or
  38  * No.  Call it like:
  39  *
  40  * <p>
  41  * <pre>
  42  * {@code
  43  *     box = application.messageBox(title, caption,
  44  *         TMessageBox.Type.OK | TMessageBox.Type.CANCEL);
  45  *
  46  *     if (box.getResult() == TMessageBox.OK) {
  47  *         ... the user pressed OK, do stuff ...
  48  *     }
  49  * }
  50  * </pre>
  51  *
  52  */
  53 public class TMessageBox extends TWindow {
  54
  55     /**
  56      * Message boxes have these supported types.
  57      */
  58     public enum Type {
  59         /**
  60          * Show an OK button.
  61          */
  62         OK,
  63
  64         /**
  65          * Show both OK and Cancel buttons.
  66          */
  67         OKCANCEL,
  68
  69         /**
  70          * Show both Yes and No buttons.
  71          */
  72         YESNO,
  73
  74         /**
  75          * Show Yes, No, and Cancel buttons.
  76          */
  77         YESNOCANCEL
  78     };
  79
  80     /**
  81      * Message boxes have these possible results.
  82      */
  83     public enum Result {
  84         /**
  85          * User clicked "OK".
  86          */
  87         OK,
  88
  89         /**
  90          * User clicked "Cancel".
  91          */
  92         CANCEL,
  93
  94         /**
  95          * User clicked "Yes".
  96          */
  97         YES,
  98
  99         /**
 100          * User clicked "No".
 101          */
 102         NO
 103     };
 104
 105
 106     /**
 107      * Which button was clicked: OK, CANCEL, YES, or NO.
 108      */
 109     private Result result = Result.OK;
 110
 111     /**
 112      * Get the result.
 113      *
 114      * @return the result: OK, CANCEL, YES, or NO.
 115      */
 116     public final Result getResult() {
 117         return result;
 118     }
 119
 120     /**
 121      * Public constructor.  The message box will be centered on screen.
 122      *
 123      * @param application TApplication that manages this window
 124      * @param title window title, will be centered along the top border
 125      * @param caption message to display.  Use embedded newlines to get a
 126      * multi-line box.
 127      */
 128     public TMessageBox(final TApplication application, final String title,
 129         final String caption) {
 130
 131         this(application, title, caption, Type.OK, true);
 132     }
 133
 134     /**
 135      * Public constructor.  The message box will be centered on screen.
 136      *
 137      * @param application TApplication that manages this window
 138      * @param title window title, will be centered along the top border
 139      * @param caption message to display.  Use embedded newlines to get a
 140      * multi-line box.
 141      * @param type one of the Type constants.  Default is Type.OK.
 142      */
 143     public TMessageBox(final TApplication application, final String title,
 144         final String caption, final Type type) {
 145
 146         this(application, title, caption, type, true);
 147     }
 148
 149     /**
 150      * Public constructor.  The message box will be centered on screen.
 151      *
 152      * @param application TApplication that manages this window
 153      * @param title window title, will be centered along the top border
 154      * @param caption message to display.  Use embedded newlines to get a
 155      * multi-line box.
 156      * @param type one of the Type constants.  Default is Type.OK.
 157      * @param yield if true, yield this Thread.  Subclasses need to set this
 158      * to false and yield at their end of their constructor intead.
 159      */
 160     protected TMessageBox(final TApplication application, final String title,
 161         final String caption, final Type type, final boolean yield) {
 162
 163         // Start as 50x50 at (1, 1).  These will be changed later.
 164         super(application, title, 1, 1, 100, 100, CENTERED | MODAL);
 165
 166         // Determine width and height
 167         String [] lines = caption.split("\n");
 168         int width = title.length() + 12;
 169         setHeight(6 + lines.length);
 170         for (String line: lines) {
 171             if (line.length() + 4 > width) {
 172                 width = line.length() + 4;
 173             }
 174         }
 175         setWidth(width);
 176         if (getWidth() > getScreen().getWidth()) {
 177             setWidth(getScreen().getWidth());
 178         }
 179         // Re-center window to get an appropriate (x, y)
 180         center();
 181
 182         // Now add my elements
 183         int lineI = 1;
 184         for (String line: lines) {
 185             addLabel(line, 1, lineI, "twindow.background.modal");
 186             lineI++;
 187         }
 188
 189         // The button line
 190         lineI++;
 191         List<TButton> buttons = new ArrayList<TButton>();
 192
 193         int buttonX = 0;
 194
 195         // Setup button actions
 196         switch (type) {
 197
 198         case OK:
 199             result = Result.OK;
 200             if (getWidth() < 15) {
 201                 setWidth(15);
 202             }
 203             buttonX = (getWidth() - 11) / 2;
 204             buttons.add(addButton("  &OK  ", buttonX, lineI,
 205                     new TAction() {
 206                         public void DO() {
 207                             result = Result.OK;
 208                             getApplication().closeWindow(TMessageBox.this);
 209                         }
 210                     }
 211                 )
 212             );
 213             break;
 214
 215         case OKCANCEL:
 216             result = Result.CANCEL;
 217             if (getWidth() < 26) {
 218                 setWidth(26);
 219             }
 220             buttonX = (getWidth() - 22) / 2;
 221             buttons.add(addButton("  &OK  ", buttonX, lineI,
 222                     new TAction() {
 223                         public void DO() {
 224                             result = Result.OK;
 225                             getApplication().closeWindow(TMessageBox.this);
 226                         }
 227                     }
 228                 )
 229             );
 230             buttonX += 8 + 4;
 231             buttons.add(addButton("&Cancel", buttonX, lineI,
 232                     new TAction() {
 233                         public void DO() {
 234                             result = Result.CANCEL;
 235                             getApplication().closeWindow(TMessageBox.this);
 236                         }
 237                     }
 238                 )
 239             );
 240             break;
 241
 242         case YESNO:
 243             result = Result.NO;
 244             if (getWidth() < 20) {
 245                 setWidth(20);
 246             }
 247             buttonX = (getWidth() - 16) / 2;
 248             buttons.add(addButton("&Yes", buttonX, lineI,
 249                     new TAction() {
 250                         public void DO() {
 251                             result = Result.YES;
 252                             getApplication().closeWindow(TMessageBox.this);
 253                         }
 254                     }
 255                 )
 256             );
 257             buttonX += 5 + 4;
 258             buttons.add(addButton("&No", buttonX, lineI,
 259                     new TAction() {
 260                         public void DO() {
 261                             result = Result.NO;
 262                             getApplication().closeWindow(TMessageBox.this);
 263                         }
 264                     }
 265                 )
 266             );
 267             break;
 268
 269         case YESNOCANCEL:
 270             result = Result.CANCEL;
 271             if (getWidth() < 31) {
 272                 setWidth(31);
 273             }
 274             buttonX = (getWidth() - 27) / 2;
 275             buttons.add(addButton("&Yes", buttonX, lineI,
 276                     new TAction() {
 277                         public void DO() {
 278                             result = Result.YES;
 279                             getApplication().closeWindow(TMessageBox.this);
 280                         }
 281                     }
 282                 )
 283             );
 284             buttonX += 5 + 4;
 285             buttons.add(addButton("&No", buttonX, lineI,
 286                     new TAction() {
 287                         public void DO() {
 288                             result = Result.NO;
 289                             getApplication().closeWindow(TMessageBox.this);
 290                         }
 291                     }
 292                 )
 293             );
 294             buttonX += 4 + 4;
 295             buttons.add(addButton("&Cancel", buttonX, lineI,
 296                     new TAction() {
 297                         public void DO() {
 298                             result = Result.CANCEL;
 299                             getApplication().closeWindow(TMessageBox.this);
 300                         }
 301                     }
 302                 )
 303             );
 304             break;
 305
 306         default:
 307             throw new IllegalArgumentException("Invalid message box type: " + type);
 308         }
 309
 310         // Set the secondaryThread to run me
 311         getApplication().enableSecondaryEventReceiver(this);
 312
 313         if (yield) {
 314             // Yield to the secondary thread.  When I come back from the
 315             // constructor response will already be set.
 316             getApplication().yield();
 317         }
 318     }
 319
 320 }