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28 2 along with this work; if not, write to the Free Software Foundation,
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31 Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
32 or visit www.oracle.com if you need additional information or have any
40 <p>
41 This document, together with the API documentation for modality-related
42 classes (such as <code>java.awt.Dialog</code>), briefly describes the new
43 modality features and how to use them. It contains the following sections:
44 </p><ul>
45 <li><a href="#Definitions">Definitions</a></li>
46 <li><a href="#ModalityTypes">Modality types</a></li>
47 <li><a href="#ShowHideBlocking">Show/hide blocking</a></li>
48 <li><a href="#ModalExclusion">Modal exclusion</a></li>
49 <li><a href="#Related">Related AWT features</a></li>
50 <li><a href="#Security">Security</a></li>
51 <li><a href="#PlatformSupport">Platform support</a></li>
52 <li><a href="#Compatibility">Compatibility</a></li>
53 <li><a href="#Examples">Examples</a></li>
54 </ul>
55
56 <a id="Definitions"></a>
57 <h2>Definitions</h2>
58
59 <p>
60 <u>Document</u> - a window without an owner that, together with
61 all its child hierarchy, may be operated on as a single self-contained
62 document.
63 Every window belongs to some document — its root can be found as
64 the closest ancestor window without an owner.
65 </p><p>
66 <a id="ModalBlocked"></a>
67 <u>Modal blocked window</u> - a window, that:
68 </p><ul>
69 <li>doesn't receive any user input events
70 </li><li>doesn't receive input focus
71 </li><li>keeps its Z-order below the modal dialog that blocks it
72 </li></ul>
73 <blockquote>
74 <hr>
75 <b>Warning!</b> Some window managers allow users to change the window
76 Z-order in an arbitrary way — in that case the last requirement
77 may not be met.
78 <hr>
79 </blockquote>
80 <p>
81 <u>Modal dialog</u> - a dialog that blocks some windows while it is
82 visible. The blocked windows are determined according to the dialog's
83 scope of blocking.
84 </p><p>
85 <u>Modal excluded window</u> - a window that stays unblocked
86 while the modal dialog is visible. If a window is modal excluded
87 then all its owned windows and child components are also excluded.
88 </p><p>
89 <u>Scope of blocking (SB)</u> - the set of windows (instances of
90 <code>java.awt.Window</code> and all derived classes) that are blocked by
91 the modal dialog while it is visible.
92 <blockquote><hr>
93 <b>Note</b>: Everywhere in this document the notion of "window" is equal
94 to a top-level window in the Java programming language — in other words
95 an instance of <code>java.awt.Window</code> or any descendant class.
96 <hr></blockquote>
97
98 <a id="ModalityTypes"></a>
99 <h2>Modality types</h2>
100
101 <p>
102 There are four supported modality types :
103 </p><ul>
104 <li>toolkit
105 </li><li>application
106 </li><li>document
107 </li><li>modeless
108 </li></ul>
109 A dialog is, by default, modeless. A modal dialog is, by default,
110 application-modal.
111 <ol>
112 <li><u>Modeless dialogs</u><br>
113 A modeless dialog doesn't block any windows while visible.
114 </li><li><u>Document-modal dialogs</u><br>
115 A document-modal dialog blocks all windows from the same
116 document except those from its child hierarchy. The document root
117 is determined as the closest ancestor window without an
118 owner.
119 </li><li><u>Application-modal dialogs</u><br>
120 An application-modal dialog blocks all windows from the same
121 application except for those from its child hierarchy.
122 If there are several applets launched in a browser, they can be
123 treated either as separate applications or a single application.
124 This behavior is implementation-dependent.
125 </li><li><u>Toolkit-modal dialogs</u><br>
126 A toolkit-modal dialog blocks all windows that run in the same
127 toolkit except those from its child hierarchy. If there
128 are several applets launched all of them run with the same toolkit,
129 so a toolkit-modal dialog shown from an applet may affect other
130 applets and all windows of the browser instance which embeds the
131 Java runtime environment for this toolkit.
132 See the security section below.
133 </li></ol>
134 <p>
135 Modality priority is arranged by the strength of blocking: modeless,
136 document-modal, application-modal and toolkit-modal. This arrangement
137 is used when determining what dialog should remain unblocked if two
138 are visible and block each other. It naturally reflects the nesting
139 of a dialog's scope of blocking (SB): a modeless dialog has an empty SB,
140 a document-modal dialog's SB is complete in some applications,
141 and all the applications are run in one toolkit. </p><p>
142 Notes about owners:
143 </p><ul>
144 <li>Creating a document-modal dialog without an owner:<br>
145 Since <code>Dialog</code> is a class derived from
146 <code>Window</code>, a <code>Dialog</code> instance automatically
147 becomes the root of the document if it has no owner. Thus, if
148 such a dialog is document-modal, its scope of blocking is empty
149 and it behaves the same way as a modeless dialog.
150 </li><li>Creating an application-modal or toolkit-modal dialog with an
151 owner:<br>
152 The scope of blocking for an application- or toolkit-modal
153 dialog, as opposed to a document-modal dialog, doesn't depend on
154 its owner. Thus, in this case the only thing that the owner
155 affects is the Z-order: the dialog always stays on top of its owner.
156 </li></ul>
157 <blockquote><hr>
158 <b>Implementation note</b>: Changing the modality type for a visible
159 dialog may have no effect until it is hidden and then shown again.
160 <hr></blockquote>
161
162 <a id="ShowHideBlocking"></a>
163 <h2>Show/hide blocking</h2>
164
165 <p>
166 <u>Showing the window or modeless dialog: "F"</u><br>
167 All the visible modal dialogs are looked through — if F is from the SB
168 of one of them, it becomes blocked by it. If there are several such
169 dialogs, the first shown is used. If no such dialogs exist, F remains
170 unblocked.
171 </p><p>
172 <u>Showing the modal dialog: "M"</u><br>
173 When modal dialog M is shown, all the visible windows fall into one of
174 three distinct groups:
175 <ul>
176 <li>Blockers of M (modal dialogs that block M and
177 either are in M's child hierarchy, or are not blocked by M, or have
178 a greater mode of modality, or block some other blocker of M)
179 <li>Blocked by M (windows from M's SB that are not blockers and are
180 not in child hierarchy of any blocker)
181 <li>All other windows (windows or modeless
182 dialogs outside M's SB and modal dialogs outside M's SB that do not
183 block M).
184 </ul>
185 <p>
186 After the modal dialog M is shown, it becomes blocked by the first shown
187 dialog from the first group (if there are any), all the windows from the
188 second one become blocked by M, and all the windows from the third group
189 remain untouched.
190 </p><p>
191 <u>In typical cases</u>, when no child dialogs are shown before their owners,
192 this rule can be simplified. (The following, simplified case, may
193 leave out some details).
194 </p><p>
195 <u>Showing the document-modal dialog: "M"</u><br>
196 All the visible application- and toolkit-modal dialogs are looked
197 through — if M is from the SB of one of them,
198 it becomes blocked by it. If there are several such dialogs,
199 the first shown is used. If no such dialogs exist, M remains unblocked.
200 </p><p>
201 <u>Showing the application-modal dialog: "M"</u><br>
202 All the visible toolkit-modal dialogs are looked through —
203 if M is from the SB of one of them, it becomes blocked by it.
204 If there are several such dialogs, the first shown is used.
205 If no such dialogs exist, M remains unblocked.
206 </p><p>
207 <u>Showing the toolkit-modal dialog: "M"</u><br>
208 M remains unblocked.
209
210 <table border="1">
211 <caption>The Standard Blocking Matrix</caption>
212 <tbody><tr>
213 <td>current/shown</td>
214 <td>frame & modeless</td>
215 <td>document</td>
216 <td>application</td>
217 <td>toolkit</td>
218 </tr>
219 <tr>
220 <td>-</td>
221 <td>-</td>
222 <td>-</td>
223 <td>-</td>
224 <td>-</td>
225 </tr>
226 <tr>
227 <td>document</td>
228 <td>blocked</td>
229 <td>-</td>
230 <td>-</td>
231 <td>-</td>
232 </tr>
233 <tr>
234 <td>application</td>
235 <td>blocked</td>
236 <td>blocked</td>
237 <td>-</td>
238 <td>-</td>
239 </tr>
240 <tr>
241 <td>toolkit</td>
242 <td>blocked</td>
243 <td>blocked</td>
244 <td>blocked</td>
245 <td>-</td>
246 </tr>
247 </tbody>
248 </table>
249 <p>
250 After the modal dialog is shown, all the windows from its SB are blocked,
251 except those that block this modal dialog.
252 </p><p>
253 <u>Hiding the window or modeless dialog: "F"</u><br>
254 If F was blocked by any modal dialog M, it becomes unblocked and is
255 removed from M's blocked windows list.
256 </p><p>
257 <u>Hiding the modal dialog: "M"</u><br>
258 If M was blocked by any other modal dialog, for example, "N",
259 it becomes unblocked and
260 is removed from N's blocked windows list. Then, all the windows and dialogs
261 blocked by M become unblocked, and after that the same checks
262 (as in Showing the modal dialog: "M")
263 are performed for each of them in the order they were initially shown.
264
265 <a id="ModalExclusion"></a>
266 </p><h2>Modal exclusion</h2>
267
268 <p>
269 There are two modal exclusion types introduced as of JDK 6
270 </p><ul>
271 <li>Exclusion from blocking of toolkit-modal dialogs
272 </li><li>Exclusion from blocking of application-modal dialogs
273 </li></ul>
274 By default, a window's modal exclusion property is turned off.
275 <ol>
276 <li><u>Application-modal exclusion</u><br>
277 If a window is application-modal excluded, it is not blocked by any
278 application-modal dialogs. Also, it is not blocked by document-modal
279 dialogs from outside of its child hierarchy.
280 </li><li><u>Toolkit-modal exclusion</u><br>
281 If a window is toolkit-modal excluded, it is not blocked
282 by any application- or toolkit-modal dialogs. Also, it is not
283 blocked by document-modal dialogs from outside of their child hierarchy.
284 </li></ol>
285 <blockquote>
286 <hr>
287 <b>Implementation note</b>: Changing the modal exclusion type for a visible window
288 may have no effect until it is hidden and then shown again.
289 </blockquote>
290
291 <a id="Related"></a>
292 <h2>Related AWT features</h2>
293
294 <p>
295 <u>Always-On-Top</u><br>
296 When a modal dialog that is not always-on-top blocks an always-on-top window,
297 their relative Z-order is unspecified and platform-dependent.
298 </p>
299 <p>
300 <u>The <code>toFront()</code> and <code>toBack()</code> methods</u><br>
301 A modal dialog should always be above all its blocked windows. Thus, if a blocked
302 window is brought to the front, its blocking dialog, if any, is also brought to the
303 front and remains above the blocked window. Likewise, if a modal dialog is sent to
304 the back, all of its blocked windows are sent to the back to keep them below the
305 blocking dialog.
306 </p>
307 <p>
308 <u>Minimizing, maximizing and closing blocked windows</u><br>
309 When a modal dialog blocks a window, the user may not be able to maximize or
310 minimize the blocked window— however, the actual behavior is unspecified
311 and platform-dependent. In any case, the user can't close the blocked window
312 interactively— but it can be closed programmatically by calling the
313 <code>setVisible(false)</code> or <code>dispose()</code> methods on the blocked
314 window.
315 </p>
316 <p>
317 <u>Blocked windows activations</u><br>
318 When the user selects a blocked window, it may be brought to the front, along
319 with the blocking modal dialog which would then become the active window—
320 however, the actual behavior is unspecified and platform-dependent.
321 </p>
322 <p>
323 <u>Hiding a modal dialog</u><br>
324 When the modal dialog that currently has focus is hidden, it is unspecified
325 and platform-dependent, which other window will become the active window.
326 Any of the following may become the active window:
327 <ol>
328 <li>The owner of the modal dialog - if the owner is unblocked.
329 </li><li>The <code>Window</code>, which was active before this modal dialog gained
330 focus - if the owner of the modal dialog is absent or is blocked.
331 </li></ol>
332 If the modal dialog to be hidden does not have focus, the active window remains
333 unchanged.
334
335 <a id="Security"></a>
336 <h2>Security</h2>
337
338 <p>
339 A special <code>AWTPermission</code>, <code>"toolkitModality"</code>,
340 is required to show toolkit-modal
341 dialogs. This would prevent, for example, blocking a browser or
342 Java Web Start (JWS) by modal dialogs shown from applets.
343 </p><p>
361 <li><code>isModalExclusionTypeSupported(modalExclusionType)</code><br>
362 Returns whether the given modal exclusion type is supported on
363 the current platform. If exclusion type "E" is not supported
364 and a window is marked as E-excluded, this has no effect.
365 </li></ul>
366
367 <a id="Compatibility"></a>
368 <h2>Compatibility</h2>
369
370 <p>
371 The default modality type is application-modal. It is used by the API
372 calls: <code>Dialog.setModal(true)</code>,
373 <code>Dialog(owner, true)</code>, etc. Prior to JDK 6
374 the default type was toolkit-modal,
375 but the only distinction between application- and toolkit-modality is for
376 applets and applications launched from Java Web Start.
377
378 <a id="Examples"></a>
379 </p><h2>Examples</h2>
380
381 <table border="0">
382 <tbody><tr>
383 <td style="text-align:left" >
384 <ol>
385 <li>Frame "F" is shown<br>
386 <li>Document-modal dialog "D<sub>i</sub>" is shown<br>
387 <li>F becomes blocked by D<sub>i</sub> — it's in the same document<br>
388 <li>Document-modal dialog "D<sub>ii</sub>" is shown<br>
389 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> — it's in the
390 same document<br>
391 </ol>
392 <br>
393 </td>
394 <td>
395 <img src="modal-example1.gif" alt="Example 1">
396 <br>
397 </td>
398 </tr>
399 <tr>
400 <td style="text-align:left">
401 <ol>
402 <li>Frame "F" is shown<br>
403 <li>Document-modal dialog "D<sub>i</sub>" is shown<br>
404 <li>F becomes blocked by D<sub>i</sub> — it's in the same document<br>
405 <li>Document-modal dialog "D<sub>ii</sub>" is shown<br>
406 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> —
407 it's in the same document<br>
408 <li>D<sub>i</sub> is hidden<br>
409 <li>F becomes blocked by D<sub>ii</sub> — it's in the same document<br>
410 </ol>
411 <br>
412 </td>
413 <td>
414 <img src="modal-example2.gif" alt="Example 2">
415 <br>
416 </td>
417 </tr>
418 <tr>
419 <td style="text-align:left">
420 <ol>
421 <li>Frame "F" is shown<br>
422 <li>Toolkit-modal dialog "D<sub>i</sub>" is created, but not shown<br>
423 <li>Document-modal dialog "D<sub>ii</sub>" is shown<br>
424 <li>F becomes blocked by D<sub>ii</sub> — it's in the same document<br>
425 <li>Application-modal dialog "D<sub>iii</sub>" is shown<br>
426 <li>D<sub>ii</sub> becomes blocked by D<sub>iii</sub> —
427 it's in the same application<br>
428 <li>D<sub>i</sub> is shown<br>
429 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> — it's its owner<br>
430 <li>D<sub>iii</sub> remains unblocked — it blocks D<sub>ii</sub> and
431 D<sub>ii</sub> blocks D<sub>i</sub><br>
432 </ol>
433 <br>
434 </td>
435 <td>
436 <img src="modal-example3.gif" alt="Example 3">
437 <br>
438 </td>
439 </tr>
440 <tr>
441 <td style="text-align:left">
442 <ol>
443 <li>Frame "F" is shown<br>
444 <li>Toolkit-modal dialog "D<sub>i</sub>" is created, but not shown<br>
445 <li>Document-modal dialog "D<sub>ii</sub>" is shown<br>
446 <li>F becomes blocked by D<sub>ii</sub> — it's in the same document<br>
447 <li>Application-modal dialog "D<sub>iii</sub>" is shown<br>
448 <li>D<sub>ii</sub> becomes blocked by D<sub>iii</sub> — it's in the
449 same application<br>
450 <li>D<sub>i</sub> is shown<br>
451 <li>D<sub>iii</sub> becomes blocked by D<sub>i</sub> — D<sub>i</sub>
452 is not blocked<br>
453 <li>D<sub>i</sub> remains unblocked<br>
454 </ol>
455 <br>
456 </td>
457 <td>
458 <img src="modal-example4.gif" alt="Example 4">
459 <br>
460 </td>
461 </tr>
462 </tbody></table>
463 </main>
464 </body></html>
|
1 <!doctype html>
2 <html lang="en">
3 <head>
4 <meta charset="utf-8"/>
5 <title>The AWT Modality</title>
6 <style>
7 td {text-align: center;}
8 tr {text-align: center;}
9 </style>
10 </head>
11 <!--
12 Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
13 DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
14
15 This code is free software; you can redistribute it and/or modify it
16 under the terms of the GNU General Public License version 2 only, as
17 published by the Free Software Foundation. Oracle designates this
18 particular file as subject to the "Classpath" exception as provided
19 by Oracle in the LICENSE file that accompanied this code.
20
21 This code is distributed in the hope that it will be useful, but WITHOUT
22 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
23 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
24 version 2 for more details (a copy is included in the LICENSE file that
25 accompanied this code).
26
27 You should have received a copy of the GNU General Public License version
28 2 along with this work; if not, write to the Free Software Foundation,
29 Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
30
31 Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
32 or visit www.oracle.com if you need additional information or have any
40 <p>
41 This document, together with the API documentation for modality-related
42 classes (such as <code>java.awt.Dialog</code>), briefly describes the new
43 modality features and how to use them. It contains the following sections:
44 </p><ul>
45 <li><a href="#Definitions">Definitions</a></li>
46 <li><a href="#ModalityTypes">Modality types</a></li>
47 <li><a href="#ShowHideBlocking">Show/hide blocking</a></li>
48 <li><a href="#ModalExclusion">Modal exclusion</a></li>
49 <li><a href="#Related">Related AWT features</a></li>
50 <li><a href="#Security">Security</a></li>
51 <li><a href="#PlatformSupport">Platform support</a></li>
52 <li><a href="#Compatibility">Compatibility</a></li>
53 <li><a href="#Examples">Examples</a></li>
54 </ul>
55
56 <a id="Definitions"></a>
57 <h2>Definitions</h2>
58
59 <p>
60 Document - a window without an owner that, together with
61 all its child hierarchy, may be operated on as a single self-contained
62 document.
63 Every window belongs to some document — its root can be found as
64 the closest ancestor window without an owner.
65 </p><p>
66 <a id="ModalBlocked"></a>
67 Modal blocked window - a window, that:
68 </p><ul>
69 <li>doesn't receive any user input events
70 </li><li>doesn't receive input focus
71 </li><li>keeps its Z-order below the modal dialog that blocks it
72 </li></ul>
73 <blockquote>
74 <hr>
75 <b>Warning!</b> Some window managers allow users to change the window
76 Z-order in an arbitrary way — in that case the last requirement
77 may not be met.
78 <hr>
79 </blockquote>
80 <p>
81 Modal dialog - a dialog that blocks some windows while it is
82 visible. The blocked windows are determined according to the dialog's
83 scope of blocking.
84 </p><p>
85 Modal excluded window - a window that stays unblocked
86 while the modal dialog is visible. If a window is modal excluded
87 then all its owned windows and child components are also excluded.
88 </p><p>
89 Scope of blocking (SB) - the set of windows (instances of
90 <code>java.awt.Window</code> and all derived classes) that are blocked by
91 the modal dialog while it is visible.
92 <blockquote><hr>
93 <b>Note</b>: Everywhere in this document the notion of "window" is equal
94 to a top-level window in the Java programming language — in other words
95 an instance of <code>java.awt.Window</code> or any descendant class.
96 <hr></blockquote>
97
98 <a id="ModalityTypes"></a>
99 <h2>Modality types</h2>
100
101 <p>
102 There are four supported modality types :
103 </p><ul>
104 <li>toolkit
105 </li><li>application
106 </li><li>document
107 </li><li>modeless
108 </li></ul>
109 A dialog is, by default, modeless. A modal dialog is, by default,
110 application-modal.
111 <ol>
112 <li>Modeless dialogs<br>
113 A modeless dialog doesn't block any windows while visible.
114 </li><li>Document-modal dialogs<br>
115 A document-modal dialog blocks all windows from the same
116 document except those from its child hierarchy. The document root
117 is determined as the closest ancestor window without an
118 owner.
119 </li><li>Application-modal dialogs<br>
120 An application-modal dialog blocks all windows from the same
121 application except for those from its child hierarchy.
122 If there are several applets launched in a browser, they can be
123 treated either as separate applications or a single application.
124 This behavior is implementation-dependent.
125 </li><li>Toolkit-modal dialogs<br>
126 A toolkit-modal dialog blocks all windows that run in the same
127 toolkit except those from its child hierarchy. If there
128 are several applets launched all of them run with the same toolkit,
129 so a toolkit-modal dialog shown from an applet may affect other
130 applets and all windows of the browser instance which embeds the
131 Java runtime environment for this toolkit.
132 See the security section below.
133 </li></ol>
134 <p>
135 Modality priority is arranged by the strength of blocking: modeless,
136 document-modal, application-modal and toolkit-modal. This arrangement
137 is used when determining what dialog should remain unblocked if two
138 are visible and block each other. It naturally reflects the nesting
139 of a dialog's scope of blocking (SB): a modeless dialog has an empty SB,
140 a document-modal dialog's SB is complete in some applications,
141 and all the applications are run in one toolkit. </p><p>
142 Notes about owners:
143 </p><ul>
144 <li>Creating a document-modal dialog without an owner:<br>
145 Since <code>Dialog</code> is a class derived from
146 <code>Window</code>, a <code>Dialog</code> instance automatically
147 becomes the root of the document if it has no owner. Thus, if
148 such a dialog is document-modal, its scope of blocking is empty
149 and it behaves the same way as a modeless dialog.
150 </li><li>Creating an application-modal or toolkit-modal dialog with an
151 owner:<br>
152 The scope of blocking for an application- or toolkit-modal
153 dialog, as opposed to a document-modal dialog, doesn't depend on
154 its owner. Thus, in this case the only thing that the owner
155 affects is the Z-order: the dialog always stays on top of its owner.
156 </li></ul>
157 <blockquote><hr>
158 <b>Implementation note</b>: Changing the modality type for a visible
159 dialog may have no effect until it is hidden and then shown again.
160 <hr></blockquote>
161
162 <a id="ShowHideBlocking"></a>
163 <h2>Show/hide blocking</h2>
164
165 <p>
166 Showing the window or modeless dialog: "F"<br>
167 All the visible modal dialogs are looked through — if F is from the SB
168 of one of them, it becomes blocked by it. If there are several such
169 dialogs, the first shown is used. If no such dialogs exist, F remains
170 unblocked.
171 </p><p>
172 Showing the modal dialog: "M"<br>
173 When modal dialog M is shown, all the visible windows fall into one of
174 three distinct groups:
175 <ul>
176 <li>Blockers of M (modal dialogs that block M and
177 either are in M's child hierarchy, or are not blocked by M, or have
178 a greater mode of modality, or block some other blocker of M)
179 <li>Blocked by M (windows from M's SB that are not blockers and are
180 not in child hierarchy of any blocker)
181 <li>All other windows (windows or modeless
182 dialogs outside M's SB and modal dialogs outside M's SB that do not
183 block M).
184 </ul>
185 <p>
186 After the modal dialog M is shown, it becomes blocked by the first shown
187 dialog from the first group (if there are any), all the windows from the
188 second one become blocked by M, and all the windows from the third group
189 remain untouched.
190 </p><p>
191 In typical cases, when no child dialogs are shown before their owners,
192 this rule can be simplified. (The following, simplified case, may
193 leave out some details).
194 </p><p>
195 Showing the document-modal dialog: "M"<br>
196 All the visible application- and toolkit-modal dialogs are looked
197 through — if M is from the SB of one of them,
198 it becomes blocked by it. If there are several such dialogs,
199 the first shown is used. If no such dialogs exist, M remains unblocked.
200 </p><p>
201 Showing the application-modal dialog: "M"<br>
202 All the visible toolkit-modal dialogs are looked through —
203 if M is from the SB of one of them, it becomes blocked by it.
204 If there are several such dialogs, the first shown is used.
205 If no such dialogs exist, M remains unblocked.
206 </p><p>
207 Showing the toolkit-modal dialog: "M"<br>
208 M remains unblocked.
209
210 <table border="1">
211 <caption>The Standard Blocking Matrix</caption>
212 <tbody><tr>
213 <th scope="col">current/shown</th>
214 <th scope="col">frame & modeless</th>
215 <th scope="col">document</th>
216 <th scope="col">application</th>
217 <th scope="col">toolkit</th>
218 </tr>
219 <tr>
220 <th scope="row">-</th>
221 <td>-</td>
222 <td>-</td>
223 <td>-</td>
224 <td>-</td>
225 </tr>
226 <tr>
227 <th scope="row">document</th>
228 <td>blocked</td>
229 <td>-</td>
230 <td>-</td>
231 <td>-</td>
232 </tr>
233 <tr>
234 <th scope="row">application</th>
235 <td>blocked</td>
236 <td>blocked</td>
237 <td>-</td>
238 <td>-</td>
239 </tr>
240 <tr>
241 <th scope="row">toolkit</th>
242 <td>blocked</td>
243 <td>blocked</td>
244 <td>blocked</td>
245 <td>-</td>
246 </tr>
247 </tbody>
248 </table>
249 <p>
250 After the modal dialog is shown, all the windows from its SB are blocked,
251 except those that block this modal dialog.
252 </p><p>
253 Hiding the window or modeless dialog: "F"<br>
254 If F was blocked by any modal dialog M, it becomes unblocked and is
255 removed from M's blocked windows list.
256 </p><p>
257 Hiding the modal dialog: "M"<br>
258 If M was blocked by any other modal dialog, for example, "N",
259 it becomes unblocked and
260 is removed from N's blocked windows list. Then, all the windows and dialogs
261 blocked by M become unblocked, and after that the same checks
262 (as in Showing the modal dialog: "M")
263 are performed for each of them in the order they were initially shown.
264
265 <a id="ModalExclusion"></a>
266 </p><h2>Modal exclusion</h2>
267
268 <p>
269 There are two modal exclusion types introduced as of JDK 6
270 </p><ul>
271 <li>Exclusion from blocking of toolkit-modal dialogs
272 </li><li>Exclusion from blocking of application-modal dialogs
273 </li></ul>
274 By default, a window's modal exclusion property is turned off.
275 <ol>
276 <li>Application-modal exclusion<br>
277 If a window is application-modal excluded, it is not blocked by any
278 application-modal dialogs. Also, it is not blocked by document-modal
279 dialogs from outside of its child hierarchy.
280 </li><li>Toolkit-modal exclusion<br>
281 If a window is toolkit-modal excluded, it is not blocked
282 by any application- or toolkit-modal dialogs. Also, it is not
283 blocked by document-modal dialogs from outside of their child hierarchy.
284 </li></ol>
285 <blockquote>
286 <hr>
287 <b>Implementation note</b>: Changing the modal exclusion type for a visible window
288 may have no effect until it is hidden and then shown again.<hr>
289 </blockquote>
290
291 <a id="Related"></a>
292 <h2>Related AWT features</h2>
293
294 <p>
295 Always-On-Top<br>
296 When a modal dialog that is not always-on-top blocks an always-on-top window,
297 their relative Z-order is unspecified and platform-dependent.
298 </p>
299 <p>
300 The <code>toFront()</code> and <code>toBack()</code> methods<br>
301 A modal dialog should always be above all its blocked windows. Thus, if a blocked
302 window is brought to the front, its blocking dialog, if any, is also brought to the
303 front and remains above the blocked window. Likewise, if a modal dialog is sent to
304 the back, all of its blocked windows are sent to the back to keep them below the
305 blocking dialog.
306 </p>
307 <p>
308 Minimizing, maximizing and closing blocked windows<br>
309 When a modal dialog blocks a window, the user may not be able to maximize or
310 minimize the blocked window— however, the actual behavior is unspecified
311 and platform-dependent. In any case, the user can't close the blocked window
312 interactively— but it can be closed programmatically by calling the
313 <code>setVisible(false)</code> or <code>dispose()</code> methods on the blocked
314 window.
315 </p>
316 <p>
317 Blocked windows activations<br>
318 When the user selects a blocked window, it may be brought to the front, along
319 with the blocking modal dialog which would then become the active window—
320 however, the actual behavior is unspecified and platform-dependent.
321 </p>
322 <p>
323 Hiding a modal dialog<br>
324 When the modal dialog that currently has focus is hidden, it is unspecified
325 and platform-dependent, which other window will become the active window.
326 Any of the following may become the active window:
327 <ol>
328 <li>The owner of the modal dialog - if the owner is unblocked.
329 </li><li>The <code>Window</code>, which was active before this modal dialog gained
330 focus - if the owner of the modal dialog is absent or is blocked.
331 </li></ol>
332 If the modal dialog to be hidden does not have focus, the active window remains
333 unchanged.
334
335 <a id="Security"></a>
336 <h2>Security</h2>
337
338 <p>
339 A special <code>AWTPermission</code>, <code>"toolkitModality"</code>,
340 is required to show toolkit-modal
341 dialogs. This would prevent, for example, blocking a browser or
342 Java Web Start (JWS) by modal dialogs shown from applets.
343 </p><p>
361 <li><code>isModalExclusionTypeSupported(modalExclusionType)</code><br>
362 Returns whether the given modal exclusion type is supported on
363 the current platform. If exclusion type "E" is not supported
364 and a window is marked as E-excluded, this has no effect.
365 </li></ul>
366
367 <a id="Compatibility"></a>
368 <h2>Compatibility</h2>
369
370 <p>
371 The default modality type is application-modal. It is used by the API
372 calls: <code>Dialog.setModal(true)</code>,
373 <code>Dialog(owner, true)</code>, etc. Prior to JDK 6
374 the default type was toolkit-modal,
375 but the only distinction between application- and toolkit-modality is for
376 applets and applications launched from Java Web Start.
377
378 <a id="Examples"></a>
379 </p><h2>Examples</h2>
380
381 <h3>Example 1</h3>
382 <ol style="float: left">
383 <li>Frame F is shown<br>
384 <li>Document-modal dialog D<sub>i</sub> is shown<br>
385 <li>F becomes blocked by D<sub>i</sub> — it's in the same document<br>
386 <li>Document-modal dialog D<sub>ii</sub> is shown<br>
387 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> — it's in the
388 same document<br>
389 </ol>
390 <p style="float: left; margin-left: 1em">
391 <img src="modal-example1.gif" alt="Example 1">
392 </p>
393
394 <h3 style="clear: left">Example 2</h3>
395 <ol style="float: left">
396 <li>Frame F is shown<br>
397 <li>Document-modal dialog D<sub>i</sub> is shown<br>
398 <li>F becomes blocked by D<sub>i</sub> — it's in the same document<br>
399 <li>Document-modal dialog D<sub>ii</sub> is shown<br>
400 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> — it's in the
401 same document<br>
402 </ol>
403 <p style="float: left; margin-left: 1em">
404 <img src="modal-example2.gif" alt="Example 2">
405 </p>
406
407 <h3 style="clear: left">Example 3</h3>
408 <ol style="float: left">
409 <li>Frame F is shown<br>
410 <li>Toolkit-modal dialog D<sub>i</sub> is created, but not shown<br>
411 <li>Document-modal dialog D<sub>ii</sub> is shown<br>
412 <li>F becomes blocked by D<sub>ii</sub> — it's in the same document<br>
413 <li>Application-modal dialog D<sub>iii</sub> is shown<br>
414 <li>D<sub>ii</sub> becomes blocked by D<sub>iii</sub> —
415 it's in the same application<br>
416 <li>D<sub>i</sub> is shown<br>
417 <li>D<sub>i</sub> becomes blocked by D<sub>ii</sub> — it's its owner<br>
418 <li>D<sub>iii</sub> remains unblocked — it blocks D<sub>ii</sub> and
419 D<sub>ii</sub> blocks D<sub>i</sub><br>
420 </ol>
421 <p style="float: left; margin-left: 1em">
422 <img src="modal-example3.gif" alt="Example 3">
423 </p>
424
425 <h3 style="clear: left">Example 4</h3>
426 <ol style="float: left">
427 <li>Frame F is shown<br>
428 <li>Toolkit-modal dialog D<sub>i</sub> is created, but not shown<br>
429 <li>Document-modal dialog D<sub>ii</sub> is shown<br>
430 <li>F becomes blocked by D<sub>ii</sub> — it's in the same document<br>
431 <li>Application-modal dialog D<sub>iii</sub> is shown<br>
432 <li>D<sub>ii</sub> becomes blocked by D<sub>iii</sub> — it's in the
433 same application<br>
434 <li>D<sub>i</sub> is shown<br>
435 <li>D<sub>iii</sub> becomes blocked by D<sub>i</sub> — D<sub>i</sub>
436 is not blocked<br>
437 <li>D<sub>i</sub> remains unblocked<br>
438 </ol>
439 <p style="float: left; margin-left: 1em">
440 <img src="modal-example4.gif" alt="Example 4">
441 </p>
442 <br style="clear:both;">
443 </main>
444 </body></html>
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