1 /*
2  * Copyright (c) 2009, 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.
8  *
9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 /*
25 * Panel is a DropTarget
26 *
27 */
28 
29 import java.awt.*;
30 import java.awt.datatransfer.*;
31 import java.awt.dnd.*;
32 import java.io.*;
33 
34 
35 class DnDTarget extends Panel implements DropTargetListener {
36     private int dragOperation = DnDConstants.ACTION_COPY | DnDConstants.ACTION_MOVE;
37     Color bgColor;
38     Color htColor;
39 
DnDTarget(Color bgColor, Color htColor)40     DnDTarget(Color bgColor, Color htColor) {
41         super();
42         this.bgColor = bgColor;
43         this.htColor = htColor;
44         setBackground(bgColor);
45         setDropTarget(new DropTarget(this, this));
46     }
47 
48 
dragEnter(DropTargetDragEvent e)49     public void dragEnter(DropTargetDragEvent e) {
50         System.out.println("[Target] dragEnter");
51         setBackground(htColor);
52         repaint();
53     }
54 
dragOver(DropTargetDragEvent e)55     public void dragOver(DropTargetDragEvent e) {
56         System.out.println("[Target] dragOver");
57     }
58 
dragExit(DropTargetEvent e)59     public void dragExit(DropTargetEvent e) {
60         System.out.println("[Target] dragExit");
61         setBackground(bgColor);
62         repaint();
63     }
64 
dragScroll(DropTargetDragEvent e)65     public void dragScroll(DropTargetDragEvent e) {
66         System.out.println("[Target] dragScroll");
67     }
68 
dropActionChanged(DropTargetDragEvent e)69     public void dropActionChanged(DropTargetDragEvent e) {
70         System.out.println("[Target] dropActionChanged");
71     }
72 
drop(DropTargetDropEvent dtde)73     public void drop(DropTargetDropEvent dtde) {
74         System.out.println("[Target] drop");
75         boolean success = false;
76         if ((dtde.getDropAction() & dragOperation) == 0) {
77             dtde.rejectDrop();
78             Label label = new Label("[no links here :) ]");
79             label.setBackground(Color.cyan);
80             add(label);
81         } else {
82             dtde.acceptDrop(dragOperation);
83             DataFlavor[] dfs = dtde.getCurrentDataFlavors();
84             if (dfs != null && dfs.length >= 1){
85                 Transferable transfer = dtde.getTransferable();
86                 try {
87                     Button button = (Button)transfer.getTransferData(dfs[0]);
88                     if( button != null ){
89                         add(button);
90                         success = true;
91                     }
92                 } catch (IOException ioe) {
93                     System.out.println(ioe.getMessage());
94                     return;
95                 } catch (UnsupportedFlavorException ufe) {
96                     System.out.println(ufe.getMessage());
97                     return;
98                 }  catch (Exception e) {
99                     System.out.println(e.getMessage());
100                     return;
101                 }
102             }
103         }
104         setBackground(bgColor);
105         dtde.dropComplete(success);
106 
107         invalidate();
108         validate();
109         repaint();
110     }
111 }
112