1 /*
2 * Copyright (c) 2009, 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 /*
27 * AWT Button is a DragSource and also a transferable object
28 */
29
30 import java.awt.*;
31 import java.awt.datatransfer.*;
32 import java.awt.dnd.*;
33 import java.io.*;
34
35 class DnDSource extends Button implements Transferable,
36 DragGestureListener,
37 DragSourceListener {
38 private DataFlavor df;
39 private transient int dropAction;
40 private final int dragOperation = DnDConstants.ACTION_COPY | DnDConstants.ACTION_MOVE | DnDConstants.ACTION_LINK;
41 DragSource dragSource = new DragSource();
42
43 DnDSource(String label) {
44 super(label);
45 setBackground(Color.yellow);
46 setForeground(Color.blue);
47 df = new DataFlavor(DnDSource.class, "DnDSource");
48
49 dragSource.createDefaultDragGestureRecognizer(
50 this,
51 dragOperation,
52 this
53 );
54 dragSource.addDragSourceListener(this);
55 }
56
57 public void changeCursor(
58 DragSourceContext dsc,
59 int ra
60 ) {
61 java.awt.Cursor c = null;
62 if ((ra & DnDConstants.ACTION_LINK) == DnDConstants.ACTION_LINK)
63 c = DragSource.DefaultLinkDrop;
64 else if ((ra & DnDConstants.ACTION_MOVE) == DnDConstants.ACTION_MOVE)
65 c = MyCursor.MOVE;//DragSource.DefaultMoveDrop;
66 else if ((ra & DnDConstants.ACTION_COPY) == DnDConstants.ACTION_COPY)
67 c = MyCursor.COPY;
68 else
69 c = MyCursor.NO_DROP;
70 dsc.setCursor(c);
71 }
72
73 /**
74 * a Drag gesture has been recognized
75 */
76
77 public void dragGestureRecognized(DragGestureEvent dge) {
78 System.out.println("starting Drag");
79 try {
80 if (DragSource.isDragImageSupported()) {
81 System.out.println("starting Imaged Drag");
82 dge.startDrag(
83 null,
84 new ImageGenerator(50, 100, new Color(0xff, 0xff, 0xff, 0x00) ) {
85 @Override public void paint(Graphics gr) {
86 gr.translate(width/2, height/2);
87 ((Graphics2D)gr).setStroke(new BasicStroke(3));
88 int R = width/4+5;
89 gr.setColor(new Color(0x00, 0x00, 0xff, 0x7F));
90 gr.fillRect(-R, -R, 2*R, 2*R);
91 gr.setColor(new Color(0x00, 0x00, 0xff, 0xff));
92 gr.drawRect(-R, -R, 2*R, 2*R);
93
94
95 gr.translate(10, -10);
96 R -= 5;
97 gr.setColor(Color.RED);
98 gr.fillOval(-R, -R, 2*R, 2*R);
99 gr.setColor(Color.MAGENTA);
100 gr.drawOval(-R, -R, 2*R, 2*R);
101 }
102 }.getImage(),
103 new Point(15, 40),
104 this,
105 this);
106 } else {
107 dge.startDrag(
108 null,
109 this,
110 this);
111 }
112 } catch (InvalidDnDOperationException e) {
113 e.printStackTrace();
114 }
115 }
116
117 /**
118 * as the hotspot enters a platform dependent drop site
119 */
120
121 public void dragEnter(DragSourceDragEvent dsde) {
122 System.out.println("[Source] dragEnter");
123 changeCursor(
124 dsde.getDragSourceContext(),
125 dsde.getUserAction() & dsde.getDropAction()
126 );
127 }
128
129 /**
130 * as the hotspot moves over a platform dependent drop site
131 */
132 public void dragOver(DragSourceDragEvent dsde) {
133 System.out.println("[Source] dragOver");
134 changeCursor(
135 dsde.getDragSourceContext(),
136 dsde.getUserAction() & dsde.getDropAction()
137 );
138 dropAction = dsde.getUserAction() & dsde.getDropAction();
139 System.out.println("dropAction = " + dropAction);
140 }
141
142 /**
143 * as the hotspot exits a platform dependent drop site
144 */
145 public void dragExit(DragSourceEvent dse) {
146 System.out.println("[Source] dragExit");
147 changeCursor(
148 dse.getDragSourceContext(),
149 DnDConstants.ACTION_NONE
150 );
151 }
152
153 /**
154 * as the operation changes
155 */
156 public void dragGestureChanged(DragSourceDragEvent dsde) {
157 System.out.println("[Source] dragGestureChanged");
158 changeCursor(
159 dsde.getDragSourceContext(),
160 dsde.getUserAction() & dsde.getDropAction()
161 );
162 dropAction = dsde.getUserAction() & dsde.getDropAction();
163 System.out.println("dropAction = " + dropAction);
164 }
165
166
167 /**
168 * as the operation completes
169 */
170 public void dragDropEnd(DragSourceDropEvent dsde) {
171 System.out.println("[Source] dragDropEnd");
172 }
173
174 public void dropActionChanged(DragSourceDragEvent dsde) {
175 System.out.println("[Source] dropActionChanged");
176 dropAction = dsde.getUserAction() & dsde.getDropAction();
177 System.out.println("dropAction = " + dropAction);
178 }
179
180 public DataFlavor[] getTransferDataFlavors() {
181 return new DataFlavor[]{df};
182 }
183
184 public boolean isDataFlavorSupported(DataFlavor sdf) {
185 return df.equals(sdf);
186 }
187
188 public Object getTransferData(DataFlavor tdf) throws UnsupportedFlavorException, IOException {
189 Object copy = null;
190 if( !df.equals(tdf) ){
191 throw new UnsupportedFlavorException(tdf);
192 }
193 Container parent = getParent();
194 switch (dropAction) {
195 case DnDConstants.ACTION_COPY:
196 try {
197 copy = this.clone();
198 } catch (CloneNotSupportedException e) {
199 ByteArrayOutputStream baos = new ByteArrayOutputStream();
200 ObjectOutputStream oos = new ObjectOutputStream(baos);
201
202 oos.writeObject(this);
203 ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
204 ObjectInputStream ois = new ObjectInputStream(bais);
205 try {
206 copy = ois.readObject();
207 } catch (ClassNotFoundException cnfe) {
208 // do nothing
209 }
210 }
211 parent.add(this);
212 return copy;
213
214 case DnDConstants.ACTION_MOVE:
215 synchronized (this) {
216 if (parent != null) {
217 parent.remove(this);
218 Label label = new Label("[empty]");
219 label.setBackground(Color.cyan);
220 label.setBounds(this.getBounds());
221 parent.add(label);
222 }
223 }
224 return this;
225
226 case DnDConstants.ACTION_LINK:
227 return this;
228
229 default:
230 return null;
231 }
232
233 }
234 }
235