1 /*
2 * Copyright (c) 2011, 2013, 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.apple.eawt.event;
27
28 import java.awt.*;
29 import java.util.*;
30 import java.util.List;
31
32 import javax.swing.*;
33
34 import java.lang.annotation.Native;
35
36 final class GestureHandler {
37 private static final String CLIENT_PROPERTY = "com.apple.eawt.event.internalGestureHandler";
38
39 // native constants for the supported types of high-level gestures
40 @Native static final int PHASE = 1;
41 @Native static final int ROTATE = 2;
42 @Native static final int MAGNIFY = 3;
43 @Native static final int SWIPE = 4;
44
45 // installs a private instance of GestureHandler, if necessary
46 static void addGestureListenerTo(final JComponent component, final GestureListener listener) {
47 final Object value = component.getClientProperty(CLIENT_PROPERTY);
48 if (value instanceof GestureHandler) {
49 ((GestureHandler)value).addListener(listener);
50 return;
51 }
52
53 if (value != null) return; // some other garbage is in our client property
54
55 final GestureHandler newHandler = new GestureHandler();
56 newHandler.addListener(listener);
57 component.putClientProperty(CLIENT_PROPERTY, newHandler);
58 }
59
60 // asks the installed GestureHandler to remove it's listener (does not uninstall the GestureHandler)
61 static void removeGestureListenerFrom(final JComponent component, final GestureListener listener) {
62 final Object value = component.getClientProperty(CLIENT_PROPERTY);
63 if (!(value instanceof GestureHandler)) return;
64 ((GestureHandler)value).removeListener(listener);
65 }
66
67
68 // called from native - finds the deepest component with an installed GestureHandler,
69 // creates a single event, and dispatches it to a recursive notifier
70 static void handleGestureFromNative(final Window window, final int type, final double x, final double y, final double a, final double b) {
71 if (window == null) return; // should never happen...
72
73 EventQueue.invokeLater(new Runnable() {
74 public void run() {
75 final Component component = SwingUtilities.getDeepestComponentAt(window, (int)x, (int)y);
76
77 final PerComponentNotifier firstNotifier;
78 if (component instanceof RootPaneContainer) {
79 firstNotifier = getNextNotifierForComponent(((RootPaneContainer)component).getRootPane());
80 } else {
81 firstNotifier = getNextNotifierForComponent(component);
82 }
83 if (firstNotifier == null) return;
84
85 switch (type) {
86 case PHASE:
87 firstNotifier.recursivelyHandlePhaseChange(a, new GesturePhaseEvent());
88 return;
89 case ROTATE:
90 firstNotifier.recursivelyHandleRotate(new RotationEvent(a));
91 return;
92 case MAGNIFY:
93 firstNotifier.recursivelyHandleMagnify(new MagnificationEvent(a));
94 return;
95 case SWIPE:
96 firstNotifier.recursivelyHandleSwipe(a, b, new SwipeEvent());
97 return;
98 }
99 }
100 });
101 }
102
103
104 final List<GesturePhaseListener> phasers = new LinkedList<GesturePhaseListener>();
105 final List<RotationListener> rotaters = new LinkedList<RotationListener>();
106 final List<MagnificationListener> magnifiers = new LinkedList<MagnificationListener>();
107 final List<SwipeListener> swipers = new LinkedList<SwipeListener>();
108
109 GestureHandler() { }
110
111 void addListener(final GestureListener listener) {
112 if (listener instanceof GesturePhaseListener) phasers.add((GesturePhaseListener)listener);
113 if (listener instanceof RotationListener) rotaters.add((RotationListener)listener);
114 if (listener instanceof MagnificationListener) magnifiers.add((MagnificationListener)listener);
115 if (listener instanceof SwipeListener) swipers.add((SwipeListener)listener);
116 }
117
118 void removeListener(final GestureListener listener) {
119 phasers.remove(listener);
120 rotaters.remove(listener);
121 magnifiers.remove(listener);
122 swipers.remove(listener);
123 }
124
125 // notifies all listeners in a particular component/handler pair
126 // and recursively notifies up the component hierarchy
127 static class PerComponentNotifier {
128 final Component component;
129 final GestureHandler handler;
130
131 public PerComponentNotifier(final Component component, final GestureHandler handler) {
132 this.component = component;
133 this.handler = handler;
134 }
135
136 void recursivelyHandlePhaseChange(final double phase, final GesturePhaseEvent e) {
137 for (final GesturePhaseListener listener : handler.phasers) {
138 if (phase < 0) {
139 listener.gestureBegan(e);
140 } else {
141 listener.gestureEnded(e);
142 }
143 if (e.isConsumed()) return;
144 }
145
146 final PerComponentNotifier next = getNextNotifierForComponent(component.getParent());
147 if (next != null) next.recursivelyHandlePhaseChange(phase, e);
148 }
149
150 void recursivelyHandleRotate(final RotationEvent e) {
151 for (final RotationListener listener : handler.rotaters) {
152 listener.rotate(e);
153 if (e.isConsumed()) return;
154 }
155
156 final PerComponentNotifier next = getNextNotifierForComponent(component.getParent());
157 if (next != null) next.recursivelyHandleRotate(e);
158 }
159
160 void recursivelyHandleMagnify(final MagnificationEvent e) {
161 for (final MagnificationListener listener : handler.magnifiers) {
162 listener.magnify(e);
163 if (e.isConsumed()) return;
164 }
165
166 final PerComponentNotifier next = getNextNotifierForComponent(component.getParent());
167 if (next != null) next.recursivelyHandleMagnify(e);
168 }
169
170 void recursivelyHandleSwipe(final double x, final double y, final SwipeEvent e) {
171 for (final SwipeListener listener : handler.swipers) {
172 if (x < 0) listener.swipedLeft(e);
173 if (x > 0) listener.swipedRight(e);
174 if (y < 0) listener.swipedDown(e);
175 if (y > 0) listener.swipedUp(e);
176 if (e.isConsumed()) return;
177 }
178
179 final PerComponentNotifier next = getNextNotifierForComponent(component.getParent());
180 if (next != null) next.recursivelyHandleSwipe(x, y, e);
181 }
182 }
183
184 // helper function to get a handler from a Component
185 static GestureHandler getHandlerForComponent(final Component c) {
186 if (!(c instanceof JComponent)) return null;
187 final Object value = ((JComponent)c).getClientProperty(CLIENT_PROPERTY);
188 if (!(value instanceof GestureHandler)) return null;
189 return (GestureHandler)value;
190 }
191
192 // recursive helper to find the next component/handler pair
193 static PerComponentNotifier getNextNotifierForComponent(final Component c) {
194 if (c == null) return null;
195
196 final GestureHandler handler = getHandlerForComponent(c);
197 if (handler != null) {
198 return new PerComponentNotifier(c, handler);
199 }
200
201 return getNextNotifierForComponent(c.getParent());
202 }
203 }