1 /*
2 * Copyright (c) 2012, 2014, 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
26 package com.sun.javafx.scene.control.behavior;
27
28 import javafx.css.PseudoClass;
29 import javafx.scene.Node;
30 import javafx.scene.control.Control;
31 import javafx.scene.control.PopupControl;
32
33 import javafx.scene.Scene;
34 import javafx.scene.input.KeyEvent;
35
36 import javafx.beans.value.ChangeListener;
37 import javafx.event.Event;
38 import javafx.event.EventDispatcher;
39 import javafx.event.EventHandler;
40 import javafx.scene.input.MouseEvent;
41
42 /**
43 * A two level focus handler allows a Control to behave as if it
44 * has three focus states :
45 * - not focused
46 * - focused with internal focus
47 * - focused with external focus
48 *
49 * In external focus mode it intercepts focus and traversal events and
50 * prevents the Controls acting upon them, or trapping focus.
51 * In internal focus mode most events go to the Control, except
52 * for events that are defined to exit the mode.
53 */
54 public class TwoLevelFocusBehavior {
55
56 Node tlNode = null;
57 PopupControl tlPopup = null;
58 EventDispatcher origEventDispatcher = null;
59
60 public TwoLevelFocusBehavior() {
61 }
62
63 public TwoLevelFocusBehavior(Node node) {
64 tlNode = node;
65 tlPopup = null;
66
67 tlNode.addEventHandler(KeyEvent.ANY, keyEventListener);
68 tlNode.addEventHandler(MouseEvent.MOUSE_PRESSED, mouseEventListener);
69 tlNode.focusedProperty().addListener(focusListener);
70
71 // block ScrollEvent from being passed down to scrollbar's skin
72 origEventDispatcher = tlNode.getEventDispatcher();
73 tlNode.setEventDispatcher(tlfEventDispatcher);
74 }
75
76 /**
77 * Invoked by the behavior when it is disposed, so that any listeners installed by
78 * the TwoLevelFocusBehavior can also be uninstalled
79 */
80 public void dispose() {
81 tlNode.removeEventHandler(KeyEvent.ANY, keyEventListener);
82 tlNode.removeEventHandler(MouseEvent.MOUSE_PRESSED, mouseEventListener);
83 tlNode.focusedProperty().removeListener(focusListener);
84 tlNode.setEventDispatcher(origEventDispatcher);
85 }
86
87 /**
88 * Don't allow the Node to handle a key event if it is in externalFocus mode.
89 * the only keyboard actions allowed are the navigation keys......
90 */
91 final EventDispatcher preemptiveEventDispatcher = (event, tail) -> {
92
93 // block the event from being passed down to children
94 if (event instanceof KeyEvent && event.getEventType() == KeyEvent.KEY_PRESSED) {
95 if (!((KeyEvent)event).isMetaDown() && !((KeyEvent)event).isControlDown() && !((KeyEvent)event).isAltDown()) {
96 if (isExternalFocus()) {
97 //
98 // don't let the behaviour leak any navigation keys when
99 // we're not in blocking mode....
100 //
101 Object obj = event.getTarget();
102
103 switch (((KeyEvent)event).getCode()) {
104 case TAB :
105 if (((KeyEvent)event).isShiftDown()) {
106 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.PREVIOUS);
107 }
108 else {
109 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.NEXT);
110 }
111 event.consume();
112 break;
113 case UP :
114 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.UP);
115 event.consume();
116 break;
117 case DOWN :
118 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.DOWN);
119 event.consume();
120 break;
121 case LEFT :
122 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.LEFT);
123 event.consume();
124 break;
125 case RIGHT :
126 ((Node)obj).impl_traverse(com.sun.javafx.scene.traversal.Direction.RIGHT);
127 event.consume();
128 break;
129 case ENTER :
130 setExternalFocus(false);
131 event.consume();
132 break;
133 default :
134 // this'll kill mnemonics.... unless!
135 Scene s = tlNode.getScene();
136 Event.fireEvent(s, event);
137 event.consume();
138 break;
139 }
140 }
141 }
142 }
143
144 return event;
145 };
146
147 final EventDispatcher tlfEventDispatcher = (event, tail) -> {
148
149 if ((event instanceof KeyEvent)) {
150 if (isExternalFocus()) {
151 tail = tail.prepend(preemptiveEventDispatcher);
152 return tail.dispatchEvent(event);
153 }
154 }
155 return origEventDispatcher.dispatchEvent(event, tail);
156 };
157
158 private Event postDispatchTidyup(Event event) {
159 // block the event from being passed down to children
160 if (event instanceof KeyEvent && event.getEventType() == KeyEvent.KEY_PRESSED) {
161 if (!isExternalFocus()) {
162 //
163 // don't let the behaviour leak any navigation keys when
164 // we're not in blocking mode....
165 //
166 if (!((KeyEvent)event).isMetaDown() && !((KeyEvent)event).isControlDown() && !((KeyEvent)event).isAltDown()) {
167
168 switch (((KeyEvent)event).getCode()) {
169 case TAB :
170 case UP :
171 case DOWN :
172 case LEFT :
173 case RIGHT :
174 event.consume();
175 break;
176 case ENTER :
177 setExternalFocus(true);
178 event.consume();
179 break;
180 default :
181 break;
182 }
183 }
184 }
185 }
186 return event;
187 }
188
189
190 private final EventHandler<KeyEvent> keyEventListener = e -> {
191 postDispatchTidyup(e);
192 };
193
194
195 /**
196 * When a node gets focus, put it in external-focus mode.
197 */
198 final ChangeListener<Boolean> focusListener = (observable, oldVal, newVal) -> {
199 if (newVal && tlPopup != null) {
200 setExternalFocus(false);
201 }
202 else {
203 setExternalFocus(true);
204 }
205 };
206
207 private final EventHandler<MouseEvent> mouseEventListener = e -> {
208 setExternalFocus(false);
209 };
210
211 private boolean externalFocus = true;
212
213 public boolean isExternalFocus() {
214 return externalFocus;
215 }
216
217 private static final PseudoClass INTERNAL_PSEUDOCLASS_STATE =
218 PseudoClass.getPseudoClass("internal-focus");
219 private static final PseudoClass EXTERNAL_PSEUDOCLASS_STATE =
220 PseudoClass.getPseudoClass("external-focus");
221
222 public void setExternalFocus(boolean value) {
223 externalFocus = value;
224
225 if (tlNode != null && tlNode instanceof Control) {
226 tlNode.pseudoClassStateChanged(INTERNAL_PSEUDOCLASS_STATE, !value);
227 tlNode.pseudoClassStateChanged(EXTERNAL_PSEUDOCLASS_STATE, value);
228 }
229 else if (tlPopup != null) {
230 tlPopup.pseudoClassStateChanged(INTERNAL_PSEUDOCLASS_STATE, !value);
231 tlPopup.pseudoClassStateChanged(EXTERNAL_PSEUDOCLASS_STATE, value);
232 }
233 }
234 }