libjava/java/awt/Dialog.java

   1 /* Dialog.java -- An AWT dialog box
   2    Copyright (C) 1999, 2000, 2001, 2002, 2005  Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.awt;
  40
  41 import java.awt.peer.DialogPeer;
  42
  43 import javax.accessibility.AccessibleContext;
  44 import javax.accessibility.AccessibleRole;
  45 import javax.accessibility.AccessibleState;
  46 import javax.accessibility.AccessibleStateSet;
  47
  48 /**
  49  * A dialog box widget class.
  50  *
  51  * @author Aaron M. Renn (arenn@urbanophile.com)
  52  * @author Tom Tromey (tromey@redhat.com)
  53  */
  54 public class Dialog extends Window
  55 {
  56
  57 /*
  58  * Static Variables
  59  */
  60
  61 // Serialization constant
  62 private static final long serialVersionUID = 5920926903803293709L;
  63
  64 /*************************************************************************/
  65
  66 /*
  67  * Instance Variables
  68  */
  69
  70 /**
  71   * @serial Indicates whether or not this dialog box is modal.
  72   */
  73 private boolean modal;
  74
  75 /**
  76   * @serial Indicates whether or not this dialog box is resizable.
  77   */
  78 private boolean resizable = true;
  79
  80 /**
  81   * @serial The title string for this dialog box, which can be
  82   * <code>null</code>.
  83   */
  84 private String title;
  85
  86 /**
  87   * This field indicates whether the dialog is undecorated or not.
  88   */
  89 private boolean undecorated = false;
  90
  91 /**
  92   * Indicates that we are blocked for modality in show
  93   */
  94 private boolean blocked = false;
  95
  96 /**
  97   * Secondary EventQueue to handle AWT events while
  98   * we are blocked for modality in show
  99   */
 100 private EventQueue eq2 = null;
 101
 102 /*************************************************************************/
 103
 104 /*
 105  * Constructors
 106  */
 107
 108 /**
 109   * Initializes a new instance of <code>Dialog</code> with the specified
 110   * parent, that is resizable and not modal, and which has no title.
 111   *
 112   * @param parent The parent frame of this dialog box.
 113   *
 114   * @exception IllegalArgumentException If the owner's GraphicsConfiguration
 115   * is not from a screen device, or if owner is null. This exception is always
 116   * thrown when GraphicsEnvironment.isHeadless() returns true.
 117   */
 118 public
 119 Dialog(Frame parent)
 120 {
 121   this(parent, "", false);
 122 }
 123
 124 /*************************************************************************/
 125
 126 /**
 127   * Initializes a new instance of <code>Dialog</code> with the specified
 128   * parent and modality, that is resizable and which has no title.
 129   *
 130   * @param parent The parent frame of this dialog box.
 131   * @param modal <code>true</code> if this dialog box is modal,
 132   * <code>false</code> otherwise.
 133   *
 134   * @exception IllegalArgumentException If the owner's GraphicsConfiguration
 135   * is not from a screen device, or if owner is null. This exception is always
 136   * thrown when GraphicsEnvironment.isHeadless() returns true.
 137   */
 138 public
 139 Dialog(Frame parent, boolean modal)
 140 {
 141   this(parent, "", modal);
 142 }
 143
 144 /*************************************************************************/
 145
 146 /**
 147   * Initializes a new instance of <code>Dialog</code> with the specified
 148   * parent, that is resizable and not modal, and which has the specified
 149   * title.
 150   *
 151   * @param parent The parent frame of this dialog box.
 152   * @param title The title string for this dialog box.
 153   *
 154   * @exception IllegalArgumentException If the owner's GraphicsConfiguration
 155   * is not from a screen device, or if owner is null. This exception is always
 156   * thrown when GraphicsEnvironment.isHeadless() returns true.
 157   */
 158 public
 159 Dialog(Frame parent, String title)
 160 {
 161   this(parent, title, false);
 162 }
 163
 164 /*************************************************************************/
 165
 166 /**
 167   * Initializes a new instance of <code>Dialog</code> with the specified,
 168   * parent, title, and modality, that is resizable.
 169   *
 170   * @param parent The parent frame of this dialog box.
 171   * @param title The title string for this dialog box.
 172   * @param modal <code>true</code> if this dialog box is modal,
 173   * <code>false</code> otherwise.
 174   *
 175   * @exception IllegalArgumentException If owner is null or
 176   * GraphicsEnvironment.isHeadless() returns true.
 177   */
 178 public
 179 Dialog(Frame parent, String title, boolean modal)
 180 {
 181   this (parent, title, modal, parent.getGraphicsConfiguration ());
 182 }
 183
 184 /**
 185  * Initializes a new instance of <code>Dialog</code> with the specified,
 186  * parent, title, modality and <code>GraphicsConfiguration</code>,
 187  * that is resizable.
 188  *
 189  * @param parent The parent frame of this dialog box.
 190  * @param title The title string for this dialog box.
 191  * @param modal <code>true</code> if this dialog box is modal,
 192  * <code>false</code> otherwise.
 193  * @param gc The <code>GraphicsConfiguration</code> object to use.
 194  *
 195  * @exception IllegalArgumentException If owner is null, the
 196  * GraphicsConfiguration is not a screen device or
 197  * GraphicsEnvironment.isHeadless() returns true.
 198  *
 199  * @since 1.4
 200  */
 201 public
 202 Dialog (Frame parent, String title, boolean modal, GraphicsConfiguration gc)
 203 {
 204   super (parent, gc);
 205
 206   // A null title is equivalent to an empty title
 207   this.title = (title != null) ? title : "";
 208   this.modal = modal;
 209   visible = false;
 210
 211   setLayout(new BorderLayout());
 212 }
 213
 214 /**
 215  * Initializes a new instance of <code>Dialog</code> with the specified,
 216  * parent, that is resizable.
 217  *
 218  * @exception IllegalArgumentException If parent is null. This exception is
 219  * always thrown when GraphicsEnvironment.isHeadless() returns true.
 220  *
 221  * @since 1.2
 222  */
 223 public
 224 Dialog (Dialog owner)
 225 {
 226   this (owner, "", false, owner.getGraphicsConfiguration ());
 227 }
 228
 229 /**
 230  * Initializes a new instance of <code>Dialog</code> with the specified,
 231  * parent and title, that is resizable.
 232  *
 233  * @exception IllegalArgumentException If parent is null. This exception is
 234  * always thrown when GraphicsEnvironment.isHeadless() returns true.
 235  *
 236  * @since 1.2
 237  */
 238 public
 239 Dialog (Dialog owner, String title)
 240 {
 241   this (owner, title, false, owner.getGraphicsConfiguration ());
 242 }
 243
 244 /**
 245  * Initializes a new instance of <code>Dialog</code> with the specified,
 246  * parent, title and modality, that is resizable.
 247  *
 248  * @exception IllegalArgumentException If parent is null. This exception is
 249  * always thrown when GraphicsEnvironment.isHeadless() returns true.
 250  *
 251  * @since 1.2
 252  */
 253 public
 254 Dialog (Dialog owner, String title, boolean modal)
 255 {
 256   this (owner, title, modal, owner.getGraphicsConfiguration ());
 257 }
 258
 259 /**
 260  * Initializes a new instance of <code>Dialog</code> with the specified,
 261  * parent, title, modality and <code>GraphicsConfiguration</code>,
 262  * that is resizable.
 263  *
 264  * @exception IllegalArgumentException If parent is null, the
 265  * GraphicsConfiguration is not a screen device or
 266  * GraphicsEnvironment.isHeadless() returns true.
 267  *
 268  * @since 1.4
 269  */
 270 public
 271 Dialog (Dialog parent, String title, boolean modal, GraphicsConfiguration gc)
 272 {
 273   super (parent, parent.getGraphicsConfiguration ());
 274
 275   // A null title is equivalent to an empty title
 276   this.title = (title != null) ? title : "";
 277   this.modal = modal;
 278   visible = false;
 279
 280   setLayout (new BorderLayout ());
 281 }
 282
 283 /*************************************************************************/
 284
 285 /*
 286  * Instance Variables
 287  */
 288
 289 /**
 290   * Returns the title of this dialog box.
 291   *
 292   * @return The title of this dialog box.
 293   */
 294 public String
 295 getTitle()
 296 {
 297   return(title);
 298 }
 299
 300 /*************************************************************************/
 301
 302 /**
 303   * Sets the title of this dialog box to the specified string.
 304   *
 305   * @param title The new title.
 306   */
 307 public synchronized void
 308 setTitle(String title)
 309 {
 310   // A null title is equivalent to an empty title
 311   this.title = (title != null) ? title : "";
 312
 313   if (peer != null)
 314     {
 315       DialogPeer d = (DialogPeer) peer;
 316       d.setTitle (title);
 317     }
 318 }
 319
 320 /*************************************************************************/
 321
 322 /**
 323   * Tests whether or not this dialog box is modal.
 324   *
 325   * @return <code>true</code> if this dialog box is modal,
 326   * <code>false</code> otherwise.
 327   */
 328 public boolean
 329 isModal()
 330 {
 331   return(modal);
 332 }
 333
 334 /*************************************************************************/
 335
 336 /**
 337   * Changes the modality of this dialog box.  This can only be done before
 338   * the peer is created.
 339   *
 340   * @param modal <code>true</code> to make this dialog box modal,
 341   * <code>false</code> to make it non-modal.
 342   */
 343 public void
 344 setModal(boolean modal)
 345 {
 346   this.modal = modal;
 347 }
 348
 349 /*************************************************************************/
 350
 351 /**
 352   * Tests whether or not this dialog box is resizable.
 353   *
 354   * @return <code>true</code> if this dialog is resizable, <code>false</code>,
 355   * otherwise.
 356   */
 357 public boolean
 358 isResizable()
 359 {
 360   return(resizable);
 361 }
 362
 363 /*************************************************************************/
 364
 365 /**
 366   * Changes the resizability of this dialog box.
 367   *
 368   * @param resizable <code>true</code> to make this dialog resizable,
 369   * <code>false</code> to make it non-resizable.
 370   */
 371 public synchronized void
 372 setResizable(boolean resizable)
 373 {
 374   this.resizable = resizable;
 375   if (peer != null)
 376     {
 377       DialogPeer d = (DialogPeer) peer;
 378       d.setResizable (resizable);
 379     }
 380 }
 381
 382 /*************************************************************************/
 383
 384 /**
 385   * Creates this object's native peer.
 386   */
 387 public synchronized void
 388 addNotify()
 389 {
 390   if (peer == null)
 391     peer = getToolkit ().createDialog (this);
 392   super.addNotify ();
 393 }
 394
 395 /*************************************************************************/
 396
 397 /**
 398   * Makes this dialog visible and brings it to the front.
 399   * If the dialog is modal and is not already visible, this call will not
 400   *  return until the dialog is hidden by someone calling hide or dispose.
 401   * If this is the event dispatching thread we must ensure that another event
 402   *  thread runs while the one which invoked this method is blocked.
 403   */
 404 public synchronized void
 405 show()
 406 {
 407   super.show();
 408
 409   if (isModal())
 410     {
 411       // If already shown (and blocked) just return
 412       if (blocked)
 413         return;
 414
 415       /* If show is called in the dispatch thread for a modal dialog it will
 416          block so we must run another thread so the events keep being
 417          dispatched.*/
 418       if (EventQueue.isDispatchThread ())
 419         {
 420           EventQueue eq = Toolkit.getDefaultToolkit().getSystemEventQueue();
 421           eq2 = new EventQueue ();
 422           eq.push (eq2);
 423         }
 424
 425       try
 426         {
 427           blocked = true;
 428           wait ();
 429           blocked = false;
 430         }
 431       catch (InterruptedException e)
 432         {
 433           blocked = false;
 434         }
 435
 436       if (eq2 != null)
 437         {
 438           eq2.pop ();
 439           eq2 = null;
 440         }
 441     }
 442 }
 443
 444 /*************************************************************************/
 445
 446 /**
 447   * Hides the Dialog and then
 448   * causes show() to return if it is currently blocked.
 449   */
 450
 451 public synchronized void
 452 hide ()
 453 {
 454   if (blocked)
 455     {
 456       notifyAll ();
 457     }
 458
 459   super.hide();
 460 }
 461
 462 /*************************************************************************/
 463
 464 /**
 465   * Disposes the Dialog and then causes show() to return
 466   * if it is currently blocked.
 467   */
 468
 469 public synchronized void
 470 dispose ()
 471 {
 472   if (blocked)
 473     {
 474       notifyAll ();
 475     }
 476
 477   super.dispose();
 478 }
 479
 480 /*************************************************************************/
 481
 482 /**
 483   * Returns a debugging string for this component.
 484   *
 485   * @return A debugging string for this component.
 486   */
 487 protected String
 488 paramString()
 489 {
 490   return ("title+" + title + ",modal=" + modal +
 491           ",resizable=" + resizable + "," + super.paramString());
 492 }
 493
 494   /**
 495    * Returns whether this frame is undecorated or not.
 496    *
 497    * @since 1.4
 498    */
 499   public boolean isUndecorated ()
 500   {
 501     return undecorated;
 502   }
 503
 504   /**
 505    * Disables or enables decorations for this frame. This method can only be
 506    * called while the frame is not displayable.
 507    *
 508    * @exception IllegalComponentStateException If this frame is displayable.
 509    *
 510    * @since 1.4
 511    */
 512   public void setUndecorated (boolean undecorated)
 513   {
 514     if (isDisplayable ())
 515       throw new IllegalComponentStateException ();
 516
 517     this.undecorated = undecorated;
 518   }
 519
 520   protected class AccessibleAWTDialog extends AccessibleAWTWindow
 521   {
 522     public AccessibleRole getAccessibleRole()
 523     {
 524       return AccessibleRole.DIALOG;
 525     }
 526
 527     public AccessibleStateSet getAccessibleState()
 528     {
 529       AccessibleStateSet states = super.getAccessibleStateSet();
 530       if (isResizable())
 531         states.add(AccessibleState.RESIZABLE);
 532       if (isModal())
 533         states.add(AccessibleState.MODAL);
 534       return states;
 535     }
 536   }
 537
 538   /**
 539    * Gets the AccessibleContext associated with this <code>Dialog</code>.
 540    * The context is created, if necessary.
 541    *
 542    * @return the associated context
 543    */
 544   public AccessibleContext getAccessibleContext()
 545   {
 546     /* Create the context if this is the first request */
 547     if (accessibleContext == null)
 548       accessibleContext = new AccessibleAWTDialog();
 549     return accessibleContext;
 550   }
 551
 552 } // class Dialog
 553