1 /*
2 * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package javafx.scene.control;
26
27 import java.lang.ref.WeakReference;
28 import java.util.Optional;
29
30 import javafx.beans.InvalidationListener;
31 import javafx.beans.property.BooleanProperty;
32 import javafx.beans.property.ObjectProperty;
33 import javafx.beans.property.ReadOnlyBooleanProperty;
34 import javafx.beans.property.ReadOnlyDoubleProperty;
35 import javafx.beans.property.SimpleObjectProperty;
36 import javafx.beans.property.StringProperty;
37 import javafx.collections.ListChangeListener;
38 import javafx.css.PseudoClass;
39 import javafx.event.Event;
40 import javafx.event.EventDispatchChain;
41 import javafx.event.EventHandler;
42 import javafx.event.EventTarget;
43 import javafx.scene.Node;
44 import javafx.scene.control.ButtonBar.ButtonData;
45 import javafx.stage.Modality;
46 import javafx.stage.Stage;
47 import javafx.stage.StageStyle;
48 import javafx.stage.Window;
49 import javafx.util.Callback;
50
51 import com.sun.javafx.event.EventHandlerManager;
52 import com.sun.javafx.tk.Toolkit;
53
54 /**
55 * A Dialog in JavaFX wraps a {@link DialogPane} and provides the necessary API
56 * to present it to end users. In JavaFX 8u40, this essentially means that the
57 * {@link DialogPane} is shown to users inside a {@link Stage}, but future releases
58 * may offer alternative options (such as 'lightweight' or 'internal' dialogs).
59 * This API therefore is intentionally ignorant of the underlying implementation,
60 * and attempts to present a common API for all possible implementations.
61 *
62 * <p>The Dialog class has a single generic type, R, which is used to represent
63 * the type of the {@link #resultProperty() result} property (and also, how to
64 * convert from {@link ButtonType} to R, through the use of the
65 * {@link #resultConverterProperty() result converter} {@link Callback}).
66 *
67 * <p><strong>Critical note:</strong> It is critical that all developers who choose
68 * to create their own dialogs by extending the Dialog class understand the
69 * importance of the {@link #resultConverterProperty() result converter} property.
70 * A result converter must always be set, whenever the R type is not
71 * {@link Void} or {@link ButtonType}. If this is not heeded, developers will find
72 * that they get ClassCastExceptions in their code, for failure to convert from
73 * {@link ButtonType} via the {@link #resultConverterProperty() result converter}.
74 *
75 * <p>It is likely that most developers would be better served using either the
76 * {@link Alert} class (for pre-defined, notification-style alerts), or either of
77 * the two pre-built dialogs ({@link TextInputDialog} and {@link ChoiceDialog}),
78 * depending on their needs.
79 *
80 * <p>Once a Dialog is instantiated, the next step is to configure it. Almost
81 * all properties on Dialog are not related to the content of the Dialog, the
82 * only exceptions are {@link #contentTextProperty()},
83 * {@link #headerTextProperty()}, and {@link #graphicProperty()}, and these
84 * properties are simply forwarding API onto the respective properties on the
85 * {@link DialogPane} stored in the {@link #dialogPaneProperty() dialog pane}
86 * property. These three properties are forwarded from DialogPane for developer
87 * convenience. For developers wanting to configure their dialog, they will in many
88 * cases be required to use code along the lines of
89 * {@code dialog.getDialogPane().setExpandableContent(node)}.
90 *
91 * <p>After configuring these properties, all that remains is to consider whether
92 * the buttons (created using {@link ButtonType} and the
93 * {@link DialogPane#createButton(ButtonType)} method) are fully configured.
94 * Developers will quickly find that the amount of configurability offered
95 * via the {@link ButtonType} class is minimal. This is intentional, but does not
96 * mean that developers can not modify the buttons created by the {@link ButtonType}
97 * that have been specified. To do this, developers simply call the
98 * {@link DialogPane#lookupButton(ButtonType)} method with the ButtonType
99 * (assuming it has already been set in the {@link DialogPane#getButtonTypes()}
100 * list. The returned Node is typically of type {@link Button}, but this depends
101 * on if the {@link DialogPane#createButton(ButtonType)} method has been overridden. A
102 * typical approach is therefore along the following lines:
103 *
104 * <pre>{@code ButtonType loginButtonType = new ButtonType("Login", ButtonData.OK_DONE);
105 * Dialog<String> dialog = new Dialog<>();
106 * dialog.getDialogPane().getButtonTypes().add(loginButtonType);
107 * boolean disabled = false; // computed based on content of text fields, for example
108 * dialog.getDialogPane().lookupButton(loginButtonType).setDisable(disabled);}</pre>
109 *
110 * <p>Once a Dialog is instantiated and fully configured, the next step is to
111 * show it. More often than not, dialogs are shown in a modal and blocking
112 * fashion. 'Modal' means that the dialog prevents user interaction with the
113 * owning application whilst it is showing, and 'blocking' means that code
114 * execution stops at the point in which the dialog is shown. This means that
115 * you can show a dialog, await the user response, and then continue running the
116 * code that directly follows the show call, giving developers the ability to
117 * immediately deal with the user input from the dialog (if relevant).
118 *
119 * <p>JavaFX dialogs are modal by default (you can change this via the
120 * {@link #initModality(javafx.stage.Modality)} API). To specify whether you want
121 * blocking or non-blocking dialogs, developers simply choose to call
122 * {@link #showAndWait()} or {@link #show()} (respectively). By default most
123 * developers should choose to use {@link #showAndWait()}, given the ease of
124 * coding in these situations. Shown below is three code snippets, showing three
125 * equally valid ways of showing a dialog:
126 *
127 * <p><strong>Option 1: The 'traditional' approach</strong>
128 * <pre>{@code Optional<ButtonType> result = dialog.showAndWait();
129 * if (result.isPresent() && result.get() == ButtonType.OK) {
130 * formatSystem();
131 * }}</pre>
132 *
133 * <p><strong>Option 2: The traditional + Optional approach</strong>
134 * <pre>{@code dialog.showAndWait().ifPresent(response -> {
135 * if (response == ButtonType.OK) {
136 * formatSystem();
137 * }
138 * });}</pre>
139 *
140 * <p><strong>Option 3: The fully lambda approach</strong>
141 * <pre>{@code dialog.showAndWait()
142 * .filter(response -> response == ButtonType.OK)
143 * .ifPresent(response -> formatSystem());}</pre>
144 *
145 * <p>There is no better or worse option of the three listed above, so developers
146 * are encouraged to work to their own style preferences. The purpose of showing
147 * the above is to help introduce developers to the {@link Optional} API, which
148 * is new in Java 8 and may be foreign to many developers.
149 *
150 * <h3>Dialog Validation / Intercepting Button Actions</h3>
151 *
152 * <p>In some circumstances it is desirable to prevent a dialog from closing
153 * until some aspect of the dialog becomes internally consistent (e.g. a form
154 * inside the dialog has all fields in a valid state). To do this, users of the
155 * dialogs API should become familiar with the
156 * {@link DialogPane#lookupButton(ButtonType)} method. By passing in a
157 * {@link javafx.scene.control.ButtonType ButtonType} (that has already been set
158 * in the {@link DialogPane#getButtonTypes() button types} list), users will be
159 * returned a Node that is typically of type {@link Button} (but this depends
160 * on if the {@link DialogPane#createButton(ButtonType)} method has been
161 * overridden). With this button, users may add an event filter that is called
162 * before the button does its usual event handling, and as such users may
163 * prevent the event handling by {@code consuming} the event. Here's a simplified
164 * example:
165 *
166 * <pre>{@code final Button btOk = (Button) dlg.getDialogPane().lookupButton(ButtonType.OK);
167 * btOk.addEventFilter(ActionEvent.ACTION, event -> {
168 * if (!validateAndStore()) {
169 * event.consume();
170 * }
171 * });}</pre>
172 *
173 * <h3>Dialog Closing Rules</h3>
174 *
175 * <p>It is important to understand what happens when a Dialog is closed, and
176 * also how a Dialog can be closed, especially in abnormal closing situations
177 * (such as when the 'X' button is clicked in a dialogs title bar, or when
178 * operating system specific keyboard shortcuts (such as alt-F4 on Windows)
179 * are entered). Fortunately, the outcome is well-defined in these situations,
180 * and can be best summarised in the following bullet points:
181 *
182 * <ul>
183 * <li>JavaFX dialogs can only be closed 'abnormally' (as defined above) in
184 * two situations:
185 * <ol>
186 * <li>When the dialog only has one button, or
187 * <li>When the dialog has multiple buttons, as long as one of them meets
188 * one of the following requirements:
189 * <ol>
190 * <li>The button has a {@link ButtonType} whose {@link ButtonData} is of type
191 * {@link ButtonData#CANCEL_CLOSE}.</li>
192 * <li>The button has a {@link ButtonType} whose {@link ButtonData} returns true
193 * when {@link ButtonData#isCancelButton()} is called.</li>
194 * </ol>
195 * </ol>
196 * <li>In all other situations, the dialog will refuse to respond to all
197 * close requests, remaining open until the user clicks on one of the available
198 * buttons in the {@link DialogPane} area of the dialog.
199 * <li>If a dialog is closed abnormally, and if the dialog contains a button
200 * which meets one of the two criteria above, the dialog will attempt to set
201 * the {@link #resultProperty() result} property to whatever value is returned
202 * from calling the {@link #resultConverterProperty() result converter} with
203 * the first matching {@link ButtonType}.
204 * <li>If for any reason the result converter returns null, or if the dialog
205 * is closed when only one non-cancel button is present, the
206 * {@link #resultProperty() result} property will be null, and the
207 * {@link #showAndWait()} method will return {@link Optional#empty()}. This
208 * later point means that, if you use either of option 2 or option 3 (as
209 * presented earlier in this class documentation), the
210 * {@link Optional#ifPresent(java.util.function.Consumer)} lambda will never
211 * be called, and code will continue executing as if the dialog had not
212 * returned any value at all.
213 * </ul>
214 *
215 * @param <R> The return type of the dialog, via the
216 * {@link #resultProperty() result} property.
217 * @see Alert
218 * @see TextInputDialog
219 * @see ChoiceDialog
220 * @since JavaFX 8u40
221 */
222 public class Dialog<R> implements EventTarget {
223
224 /**************************************************************************
225 *
226 * Static fields
227 *
228 **************************************************************************/
229
230
231
232
233 /**************************************************************************
234 *
235 * Static methods
236 *
237 **************************************************************************/
238
239
240
241 /**************************************************************************
242 *
243 * Private fields
244 *
245 **************************************************************************/
246
247 final FXDialog dialog;
248
249 private boolean isClosing;
250
251
252
253 /**************************************************************************
254 *
255 * Constructors
256 *
257 **************************************************************************/
258
259 /**
260 * Creates a dialog without a specified owner.
261 */
262 public Dialog() {
263 this.dialog = new HeavyweightDialog(this);
264 setDialogPane(new DialogPane());
265 initModality(Modality.APPLICATION_MODAL);
266 }
267
268
269
270 /**************************************************************************
271 *
272 * Abstract methods
273 *
274 **************************************************************************/
275
276
277
278
279 /**************************************************************************
280 *
281 * Public API
282 *
283 **************************************************************************/
284
285 /**
286 * Shows the dialog but does not wait for a user response (in other words,
287 * this brings up a non-blocking dialog). Users of this API must either
288 * poll the {@link #resultProperty() result property}, or else add a listener
289 * to the result property to be informed of when it is set.
290 * @throws IllegalStateException if this method is called on a thread
291 * other than the JavaFX Application Thread.
292 */
293 public final void show() {
294 Toolkit.getToolkit().checkFxUserThread();
295
296 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_SHOWING));
297 if (Double.isNaN(getWidth()) && Double.isNaN(getHeight())) {
298 dialog.sizeToScene();
299 }
300
301 dialog.show();
302
303 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_SHOWN));
304 }
305
306 /**
307 * Shows the dialog and waits for the user response (in other words, brings
308 * up a blocking dialog, with the returned value the users input).
309 * <p>
310 * This method must be called on the JavaFX Application thread.
311 * Additionally, it must either be called from an input event handler or
312 * from the run method of a Runnable passed to
313 * {@link javafx.application.Platform#runLater Platform.runLater}.
314 * It must not be called during animation or layout processing.
315 * </p>
316 *
317 * @return An {@link Optional} that contains the {@link #resultProperty() result}.
318 * Refer to the {@link Dialog} class documentation for more detail.
319 * @throws IllegalStateException if this method is called on a thread
320 * other than the JavaFX Application Thread.
321 * @throws IllegalStateException if this method is called during
322 * animation or layout processing.
323 */
324 public final Optional<R> showAndWait() {
325 Toolkit.getToolkit().checkFxUserThread();
326
327 if (!Toolkit.getToolkit().canStartNestedEventLoop()) {
328 throw new IllegalStateException("showAndWait is not allowed during animation or layout processing");
329 }
330
331 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_SHOWING));
332 if (Double.isNaN(getWidth()) && Double.isNaN(getHeight())) {
333 dialog.sizeToScene();
334 }
335
336
337 // this is slightly odd - we fire the SHOWN event before the show()
338 // call, so that users get the event before the dialog blocks
339 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_SHOWN));
340
341 dialog.showAndWait();
342
343 return Optional.ofNullable(getResult());
344 }
345
346 /**
347 * Hides the dialog.
348 */
349 public final void close() {
350 if (isClosing) return;
351 isClosing = true;
352
353 final R result = getResult();
354
355 // if the result is null and we do not have permission to close the
356 // dialog, then we cancel the close request before any events are
357 // even fired
358 if (result == null && ! dialog.requestPermissionToClose(this)) {
359 isClosing = false;
360 return;
361 }
362
363 // if we are here we have permission to close the dialog. However, we
364 // may not have a result set to return to the user. Therefore, we need
365 // to handle that before the dialog closes (especially in case the
366 // dialog is blocking, in which case having a null result is really going
367 // to mess up users).
368 //
369 // In cases where the result is null, and where the dialog has a cancel
370 // button, we call into the result converter to see what to do. This is
371 // used primarily to handle the requirement that the X button has the
372 // same result as clicking the cancel button.
373 //
374 // A 'cancel button' can mean two different things (although they may
375 // be the same thing):
376 // 1) A button whose ButtonData is of type CANCEL_CLOSE.
377 // 2) A button whose ButtonData returns true for isCancelButton().
378 if (result == null) {
379 ButtonType cancelButton = null;
380
381 // we do two things here. We are primarily looking for a button with
382 // ButtonData.CANCEL_CLOSE. If we find one, we use it as the result.
383 // However, if we don't find one, we can also use any button that
384 // is a cancel button.
385 for (ButtonType button : getDialogPane().getButtonTypes()) {
386 ButtonData buttonData = button.getButtonData();
387 if (buttonData == null) continue;
388
389 if (buttonData == ButtonData.CANCEL_CLOSE) {
390 cancelButton = button;
391 break;
392 }
393 if (buttonData.isCancelButton()) {
394 cancelButton = button;
395 }
396 }
397
398 setResultAndClose(cancelButton, false);
399 }
400
401 // start normal closing process
402 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_HIDING));
403
404 DialogEvent closeRequestEvent = new DialogEvent(this, DialogEvent.DIALOG_CLOSE_REQUEST);
405 Event.fireEvent(this, closeRequestEvent);
406 if (closeRequestEvent.isConsumed()) {
407 isClosing = false;
408 return;
409 }
410
411 dialog.close();
412
413 Event.fireEvent(this, new DialogEvent(this, DialogEvent.DIALOG_HIDDEN));
414
415 isClosing = false;
416 }
417
418 /**
419 * closes the dialog.
420 */
421 public final void hide() {
422 close();
423 }
424
425 /**
426 * Specifies the modality for this dialog. This must be done prior to making
427 * the dialog visible. The modality is one of: Modality.NONE,
428 * Modality.WINDOW_MODAL, or Modality.APPLICATION_MODAL.
429 *
430 * @param modality the modality for this dialog.
431 *
432 * @throws IllegalStateException if this property is set after the dialog
433 * has ever been made visible.
434 *
435 * @defaultValue Modality.APPLICATION_MODAL
436 */
437 public final void initModality(Modality modality) {
438 dialog.initModality(modality);
439 }
440
441 /**
442 * Retrieves the modality attribute for this dialog.
443 *
444 * @return the modality.
445 */
446 public final Modality getModality() {
447 return dialog.getModality();
448 }
449
450 /**
451 * Specifies the style for this dialog. This must be done prior to making
452 * the dialog visible. The style is one of: StageStyle.DECORATED,
453 * StageStyle.UNDECORATED, StageStyle.TRANSPARENT, StageStyle.UTILITY,
454 * or StageStyle.UNIFIED.
455 *
456 * @param style the style for this dialog.
457 *
458 * @throws IllegalStateException if this property is set after the dialog
459 * has ever been made visible.
460 *
461 * @defaultValue StageStyle.DECORATED
462 */
463 public final void initStyle(StageStyle style) {
464 dialog.initStyle(style);
465 }
466
467 /**
468 * Specifies the owner {@link Window} for this dialog, or null for a top-level,
469 * unowned dialog. This must be done prior to making the dialog visible.
470 *
471 * @param window the owner {@link Window} for this dialog.
472 *
473 * @throws IllegalStateException if this property is set after the dialog
474 * has ever been made visible.
475 *
476 * @defaultValue null
477 */
478 public final void initOwner(Window window) {
479 dialog.initOwner(window);
480 }
481
482 /**
483 * Retrieves the owner Window for this dialog, or null for an unowned dialog.
484 *
485 * @return the owner Window.
486 */
487 public final Window getOwner() {
488 return dialog.getOwner();
489 }
490
491
492
493 /**************************************************************************
494 *
495 * Properties
496 *
497 **************************************************************************/
498
499 // --- dialog Pane
500 /**
501 * The root node of the dialog, the {@link DialogPane} contains all visual
502 * elements shown in the dialog. As such, it is possible to completely adjust
503 * the display of the dialog by modifying the existing dialog pane or creating
504 * a new one.
505 */
506 private ObjectProperty<DialogPane> dialogPane = new SimpleObjectProperty<DialogPane>(this, "dialogPane", new DialogPane()) {
507 final InvalidationListener expandedListener = o -> {
508 DialogPane dialogPane = getDialogPane();
509 if (dialogPane == null) return;
510
511 final Node content = dialogPane.getExpandableContent();
512 final boolean isExpanded = content == null ? false : content.isVisible();
513 setResizable(isExpanded);
514
515 Dialog.this.dialog.sizeToScene();
516 };
517
518 final InvalidationListener headerListener = o -> {
519 updatePseudoClassState();
520 };
521
522 WeakReference<DialogPane> dialogPaneRef = new WeakReference<>(null);
523
524 protected void invalidated() {
525 DialogPane oldDialogPane = dialogPaneRef.get();
526 if (oldDialogPane != null) {
527 // clean up
528 oldDialogPane.expandedProperty().removeListener(expandedListener);
529 oldDialogPane.headerProperty().removeListener(headerListener);
530 oldDialogPane.headerTextProperty().removeListener(headerListener);
531 oldDialogPane.setDialog(null);
532 }
533
534 final DialogPane newDialogPane = getDialogPane();
535
536 if (newDialogPane != null) {
537 newDialogPane.setDialog(Dialog.this);
538
539 // if the buttons change, we dynamically update the dialog
540 newDialogPane.getButtonTypes().addListener((ListChangeListener<ButtonType>) c -> {
541 newDialogPane.requestLayout();
542 });
543 newDialogPane.expandedProperty().addListener(expandedListener);
544 newDialogPane.headerProperty().addListener(headerListener);
545 newDialogPane.headerTextProperty().addListener(headerListener);
546
547 updatePseudoClassState();
548 newDialogPane.requestLayout();
549 }
550
551 // push the new dialog down into the implementation for rendering
552 dialog.setDialogPane(newDialogPane);
553
554 dialogPaneRef = new WeakReference<DialogPane>(newDialogPane);
555 }
556 };
557
558 public final ObjectProperty<DialogPane> dialogPaneProperty() {
559 return dialogPane;
560 }
561
562 public final DialogPane getDialogPane() {
563 return dialogPane.get();
564 }
565
566 public final void setDialogPane(DialogPane value) {
567 dialogPane.set(value);
568 }
569
570
571 // --- content text (forwarded from DialogPane)
572 /**
573 * A property representing the content text for the dialog pane. The content text
574 * is lower precedence than the {@link DialogPane#contentProperty() content node}, meaning
575 * that if both the content node and the contentText properties are set, the
576 * content text will not be displayed in a default DialogPane instance.
577 */
578 public final StringProperty contentTextProperty() {
579 return getDialogPane().contentTextProperty();
580 }
581
582 /**
583 * Returns the currently-set content text for this DialogPane.
584 */
585 public final String getContentText() {
586 return getDialogPane().getContentText();
587 }
588
589 /**
590 * Sets the string to show in the dialog content area. Note that the content text
591 * is lower precedence than the {@link DialogPane#contentProperty() content node}, meaning
592 * that if both the content node and the contentText properties are set, the
593 * content text will not be displayed in a default DialogPane instance.
594 */
595 public final void setContentText(String contentText) {
596 getDialogPane().setContentText(contentText);
597 }
598
599
600 // --- header text (forwarded from DialogPane)
601 /**
602 * A property representing the header text for the dialog pane. The header text
603 * is lower precedence than the {@link DialogPane#headerProperty() header node}, meaning
604 * that if both the header node and the headerText properties are set, the
605 * header text will not be displayed in a default DialogPane instance.
606 */
607 public final StringProperty headerTextProperty() {
608 return getDialogPane().headerTextProperty();
609 }
610
611 /**
612 * Returns the currently-set header text for this DialogPane.
613 */
614 public final String getHeaderText() {
615 return getDialogPane().getHeaderText();
616 }
617
618 /**
619 * Sets the string to show in the dialog header area. Note that the header text
620 * is lower precedence than the {@link DialogPane#headerProperty() header node}, meaning
621 * that if both the header node and the headerText properties are set, the
622 * header text will not be displayed in a default DialogPane instance.
623 */
624 public final void setHeaderText(String headerText) {
625 getDialogPane().setHeaderText(headerText);
626 }
627
628
629 // --- graphic (forwarded from DialogPane)
630 /**
631 * The dialog graphic, presented either in the header, if one is showing, or
632 * to the left of the {@link DialogPane#contentProperty() content}.
633 *
634 * @return An ObjectProperty wrapping the current graphic.
635 */
636 public final ObjectProperty<Node> graphicProperty() {
637 return getDialogPane().graphicProperty();
638 }
639
640 public final Node getGraphic() {
641 return getDialogPane().getGraphic();
642 }
643
644 /**
645 * Sets the dialog graphic, which will be displayed either in the header, if
646 * one is showing, or to the left of the {@link DialogPane#contentProperty() content}.
647 *
648 * @param graphic
649 * The new dialog graphic, or null if no graphic should be shown.
650 */
651 public final void setGraphic(Node graphic) {
652 getDialogPane().setGraphic(graphic);
653 }
654
655
656 // --- result
657 private final ObjectProperty<R> resultProperty = new SimpleObjectProperty<R>() {
658 protected void invalidated() {
659 close();
660 }
661 };
662
663 /**
664 * A property representing what has been returned from the dialog. A result
665 * is generated through the {@link #resultConverterProperty() result converter},
666 * which is intended to convert from the {@link ButtonType} that the user
667 * clicked on into a value of type R. Refer to the {@link Dialog} class
668 * JavaDoc for more details.
669 */
670 public final ObjectProperty<R> resultProperty() {
671 return resultProperty;
672 }
673
674 public final R getResult() {
675 return resultProperty().get();
676 }
677
678 public final void setResult(R value) {
679 this.resultProperty().set(value);
680 }
681
682
683 // --- result converter
684 private final ObjectProperty<Callback<ButtonType, R>> resultConverterProperty
685 = new SimpleObjectProperty<>(this, "resultConverter");
686
687 /**
688 * API to convert the {@link ButtonType} that the user clicked on into a
689 * result that can be returned via the {@link #resultProperty() result}
690 * property. This is necessary as {@link ButtonType} represents the visual
691 * button within the dialog, and do not know how to map themselves to a valid
692 * result - that is a requirement of the dialog implementation by making use
693 * of the result converter. In some cases, the result type of a Dialog
694 * subclass is ButtonType (which means that the result converter can be null),
695 * but in some cases (where the result type, R, is not ButtonType or Void),
696 * this callback must be specified.
697 */
698 public final ObjectProperty<Callback<ButtonType, R>> resultConverterProperty() {
699 return resultConverterProperty;
700 }
701
702 public final Callback<ButtonType, R> getResultConverter() {
703 return resultConverterProperty().get();
704 }
705
706 public final void setResultConverter(Callback<ButtonType, R> value) {
707 this.resultConverterProperty().set(value);
708 }
709
710
711 // --- showing
712 /**
713 * Represents whether the dialog is currently showing.
714 */
715 public final ReadOnlyBooleanProperty showingProperty() {
716 return dialog.showingProperty();
717 }
718
719 /**
720 * Returns whether or not the dialog is showing.
721 *
722 * @return true if dialog is showing.
723 */
724 public final boolean isShowing() {
725 return showingProperty().get();
726 }
727
728
729 // --- resizable
730 /**
731 * Represents whether the dialog is resizable.
732 */
733 public final BooleanProperty resizableProperty() {
734 return dialog.resizableProperty();
735 }
736
737 /**
738 * Returns whether or not the dialog is resizable.
739 *
740 * @return true if dialog is resizable.
741 */
742 public final boolean isResizable() {
743 return resizableProperty().get();
744 }
745
746 /**
747 * Sets whether the dialog can be resized by the user.
748 * Resizable dialogs can also be maximized ( maximize button
749 * becomes visible)
750 *
751 * @param resizable true if dialog should be resizable.
752 */
753 public final void setResizable(boolean resizable) {
754 resizableProperty().set(resizable);
755 }
756
757
758 // --- width
759 /**
760 * Property representing the width of the dialog.
761 */
762 public final ReadOnlyDoubleProperty widthProperty() {
763 return dialog.widthProperty();
764 }
765
766 /**
767 * Returns the width of the dialog.
768 */
769 public final double getWidth() {
770 return widthProperty().get();
771 }
772
773 /**
774 * Sets the width of the dialog.
775 */
776 public final void setWidth(double width) {
777 dialog.setWidth(width);
778 }
779
780
781 // --- height
782 /**
783 * Property representing the height of the dialog.
784 */
785 public final ReadOnlyDoubleProperty heightProperty() {
786 return dialog.heightProperty();
787 }
788
789 /**
790 * Returns the height of the dialog.
791 */
792 public final double getHeight() {
793 return heightProperty().get();
794 }
795
796 /**
797 * Sets the height of the dialog.
798 */
799 public final void setHeight(double height) {
800 dialog.setHeight(height);
801 }
802
803
804 // --- title
805 /**
806 * Return the titleProperty of the dialog.
807 */
808 public final StringProperty titleProperty(){
809 return this.dialog.titleProperty();
810 }
811
812 /**
813 * Return the title of the dialog.
814 */
815 public final String getTitle(){
816 return this.dialog.titleProperty().get();
817 }
818 /**
819 * Change the Title of the dialog.
820 * @param title
821 */
822 public final void setTitle(String title){
823 this.dialog.titleProperty().set(title);
824 }
825
826
827 // --- x
828 public final double getX() {
829 return dialog.getX();
830 }
831
832 public final void setX(double x) {
833 dialog.setX(x);
834 }
835
836 /**
837 * The horizontal location of this {@code Dialog}. Changing this attribute
838 * will move the {@code Dialog} horizontally.
839 */
840 public final ReadOnlyDoubleProperty xProperty() {
841 return dialog.xProperty();
842 }
843
844 // --- y
845 public final double getY() {
846 return dialog.getY();
847 }
848
849 public final void setY(double y) {
850 dialog.setY(y);
851 }
852
853 /**
854 * The vertical location of this {@code Dialog}. Changing this attribute
855 * will move the {@code Dialog} vertically.
856 */
857 public final ReadOnlyDoubleProperty yProperty() {
858 return dialog.yProperty();
859 }
860
861
862
863 /***************************************************************************
864 *
865 * Events
866 *
867 **************************************************************************/
868
869 private final EventHandlerManager eventHandlerManager = new EventHandlerManager(this);
870
871 /** {@inheritDoc} */
872 @Override public EventDispatchChain buildEventDispatchChain(EventDispatchChain tail) {
873 return tail.prepend(eventHandlerManager);
874 }
875
876 /**
877 * Called just prior to the Dialog being shown.
878 */
879 private ObjectProperty<EventHandler<DialogEvent>> onShowing;
880 public final void setOnShowing(EventHandler<DialogEvent> value) { onShowingProperty().set(value); }
881 public final EventHandler<DialogEvent> getOnShowing() {
882 return onShowing == null ? null : onShowing.get();
883 }
884 public final ObjectProperty<EventHandler<DialogEvent>> onShowingProperty() {
885 if (onShowing == null) {
886 onShowing = new SimpleObjectProperty<EventHandler<DialogEvent>>(this, "onShowing") {
887 @Override protected void invalidated() {
888 eventHandlerManager.setEventHandler(DialogEvent.DIALOG_SHOWING, get());
889 }
890 };
891 }
892 return onShowing;
893 }
894
895 /**
896 * Called just after the Dialog is shown.
897 */
898 private ObjectProperty<EventHandler<DialogEvent>> onShown;
899 public final void setOnShown(EventHandler<DialogEvent> value) { onShownProperty().set(value); }
900 public final EventHandler<DialogEvent> getOnShown() {
901 return onShown == null ? null : onShown.get();
902 }
903 public final ObjectProperty<EventHandler<DialogEvent>> onShownProperty() {
904 if (onShown == null) {
905 onShown = new SimpleObjectProperty<EventHandler<DialogEvent>>(this, "onShown") {
906 @Override protected void invalidated() {
907 eventHandlerManager.setEventHandler(DialogEvent.DIALOG_SHOWN, get());
908 }
909 };
910 }
911 return onShown;
912 }
913
914 /**
915 * Called just prior to the Dialog being hidden.
916 */
917 private ObjectProperty<EventHandler<DialogEvent>> onHiding;
918 public final void setOnHiding(EventHandler<DialogEvent> value) { onHidingProperty().set(value); }
919 public final EventHandler<DialogEvent> getOnHiding() {
920 return onHiding == null ? null : onHiding.get();
921 }
922 public final ObjectProperty<EventHandler<DialogEvent>> onHidingProperty() {
923 if (onHiding == null) {
924 onHiding = new SimpleObjectProperty<EventHandler<DialogEvent>>(this, "onHiding") {
925 @Override protected void invalidated() {
926 eventHandlerManager.setEventHandler(DialogEvent.DIALOG_HIDING, get());
927 }
928 };
929 }
930 return onHiding;
931 }
932
933 /**
934 * Called just after the Dialog has been hidden.
935 * When the {@code Dialog} is hidden, this event handler is invoked allowing
936 * the developer to clean up resources or perform other tasks when the
937 * {@link Alert} is closed.
938 */
939 private ObjectProperty<EventHandler<DialogEvent>> onHidden;
940 public final void setOnHidden(EventHandler<DialogEvent> value) { onHiddenProperty().set(value); }
941 public final EventHandler<DialogEvent> getOnHidden() {
942 return onHidden == null ? null : onHidden.get();
943 }
944 public final ObjectProperty<EventHandler<DialogEvent>> onHiddenProperty() {
945 if (onHidden == null) {
946 onHidden = new SimpleObjectProperty<EventHandler<DialogEvent>>(this, "onHidden") {
947 @Override protected void invalidated() {
948 eventHandlerManager.setEventHandler(DialogEvent.DIALOG_HIDDEN, get());
949 }
950 };
951 }
952 return onHidden;
953 }
954
955 /**
956 * Called when there is an external request to close this {@code Dialog}.
957 * The installed event handler can prevent dialog closing by consuming the
958 * received event.
959 */
960 private ObjectProperty<EventHandler<DialogEvent>> onCloseRequest;
961 public final void setOnCloseRequest(EventHandler<DialogEvent> value) {
962 onCloseRequestProperty().set(value);
963 }
964 public final EventHandler<DialogEvent> getOnCloseRequest() {
965 return (onCloseRequest != null) ? onCloseRequest.get() : null;
966 }
967 public final ObjectProperty<EventHandler<DialogEvent>>
968 onCloseRequestProperty() {
969 if (onCloseRequest == null) {
970 onCloseRequest = new SimpleObjectProperty<EventHandler<DialogEvent>>(this, "onCloseRequest") {
971 @Override protected void invalidated() {
972 eventHandlerManager.setEventHandler(DialogEvent.DIALOG_CLOSE_REQUEST, get());
973 }
974 };
975 }
976 return onCloseRequest;
977 }
978
979
980
981 /***************************************************************************
982 *
983 * Private implementation
984 *
985 **************************************************************************/
986
987 // This code is called both in the normal and in the abnormal case (i.e.
988 // both when a button is clicked and when the user forces a window closed
989 // with keyboard OS-specific shortchuts or OS-native titlebar buttons).
990 @SuppressWarnings("unchecked")
991 void setResultAndClose(ButtonType cmd, boolean close) {
992 Callback<ButtonType, R> resultConverter = getResultConverter();
993
994 R priorResultValue = getResult();
995 R newResultValue = null;
996
997 if (resultConverter == null) {
998 // The choice to cast cmd to R here was a conscious decision, taking
999 // into account the choices available to us. Firstly, to summarise the
1000 // issue, at this point here we have a null result converter, and no
1001 // idea how to convert the given ButtonType to R. Our options are:
1002 //
1003 // 1) We could throw an exception here, but this requires that all
1004 // developers who create a dialog set a result converter (at least
1005 // setResultConverter(buttonType -> (R) buttonType)). This is
1006 // non-intuitive and depends on the developer reading documentation.
1007 //
1008 // 2) We could set a default result converter in the resultConverter
1009 // property that does the identity conversion. This saves people from
1010 // having to set a default result converter, but it is a little odd
1011 // that the result converter is non-null by default.
1012 //
1013 // 3) We can cast the button type here, which is what we do. This means
1014 // that the result converter is null by default.
1015 //
1016 // In the case of option 1), developers will receive a NPE when the
1017 // dialog is closed, regardless of how it was closed. In the case of
1018 // option 2) and 3), the user unfortunately receives a ClassCastException
1019 // in their code. This is unfortunate as it is not immediately obvious
1020 // why the ClassCastException occurred, and how to resolve it. However,
1021 // we decided to take this later approach as it prevents the issue of
1022 // requiring all custom dialog developers from having to supply their
1023 // own result converters.
1024 newResultValue = (R) cmd;
1025 } else {
1026 newResultValue = resultConverter.call(cmd);
1027 }
1028
1029 setResult(newResultValue);
1030
1031 // fix for the case where we set the same result as what
1032 // was already set. We should still close the dialog, but
1033 // we need to special-case it here, as the result property
1034 // won't fire any event if the value won't change.
1035 if (close && priorResultValue == newResultValue) {
1036 close();
1037 }
1038 }
1039
1040
1041
1042
1043 /***************************************************************************
1044 *
1045 * Stylesheet Handling
1046 *
1047 **************************************************************************/
1048 private static final PseudoClass HEADER_PSEUDO_CLASS =
1049 PseudoClass.getPseudoClass("header"); //$NON-NLS-1$
1050 private static final PseudoClass NO_HEADER_PSEUDO_CLASS =
1051 PseudoClass.getPseudoClass("no-header"); //$NON-NLS-1$
1052
1053 private void updatePseudoClassState() {
1054 DialogPane dialogPane = getDialogPane();
1055 if (dialogPane != null) {
1056 final boolean hasHeader = getDialogPane().hasHeader();
1057 dialogPane.pseudoClassStateChanged(HEADER_PSEUDO_CLASS, hasHeader);
1058 dialogPane.pseudoClassStateChanged(NO_HEADER_PSEUDO_CLASS, !hasHeader);
1059 }
1060 }
1061 }