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/*
* Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* AWT Button is a DragSource and also a transferable object
*/
import java.awt.*;
import java.awt.datatransfer.*;
import java.awt.dnd.*;
import java.io.*;
class DnDSource extends Button implements Transferable,
DragGestureListener,
DragSourceListener {
private DataFlavor df;
private transient int dropAction;
private final int dragOperation = DnDConstants.ACTION_COPY | DnDConstants.ACTION_MOVE | DnDConstants.ACTION_LINK;
DragSource dragSource = new DragSource();
DnDSource(String label) {
super(label);
setBackground(Color.yellow);
setForeground(Color.blue);
df = new DataFlavor(DnDSource.class, "DnDSource");
dragSource.createDefaultDragGestureRecognizer(
this,
dragOperation,
this
);
dragSource.addDragSourceListener(this);
}
public void changeCursor(
DragSourceContext dsc,
int ra
) {
java.awt.Cursor c = null;
if ((ra & DnDConstants.ACTION_LINK) == DnDConstants.ACTION_LINK)
c = DragSource.DefaultLinkDrop;
else if ((ra & DnDConstants.ACTION_MOVE) == DnDConstants.ACTION_MOVE)
c = MyCursor.MOVE;//DragSource.DefaultMoveDrop;
else if ((ra & DnDConstants.ACTION_COPY) == DnDConstants.ACTION_COPY)
c = MyCursor.COPY;
else
c = MyCursor.NO_DROP;
dsc.setCursor(c);
}
/**
* a Drag gesture has been recognized
*/
public void dragGestureRecognized(DragGestureEvent dge) {
System.out.println("starting Drag");
try {
if (DragSource.isDragImageSupported()) {
System.out.println("starting Imaged Drag");
dge.startDrag(
null,
new ImageGenerator(50, 100, new Color(0xff, 0xff, 0xff, 0x00) ) {
@Override public void paint(Graphics gr) {
gr.translate(width/2, height/2);
((Graphics2D)gr).setStroke(new BasicStroke(3));
int R = width/4+5;
gr.setColor(new Color(0x00, 0x00, 0xff, 0x7F));
gr.fillRect(-R, -R, 2*R, 2*R);
gr.setColor(new Color(0x00, 0x00, 0xff, 0xff));
gr.drawRect(-R, -R, 2*R, 2*R);
gr.translate(10, -10);
R -= 5;
gr.setColor(Color.RED);
gr.fillOval(-R, -R, 2*R, 2*R);
gr.setColor(Color.MAGENTA);
gr.drawOval(-R, -R, 2*R, 2*R);
}
}.getImage(),
new Point(15, 40),
this,
this);
} else {
dge.startDrag(
null,
this,
this);
}
} catch (InvalidDnDOperationException e) {
e.printStackTrace();
}
}
/**
* as the hotspot enters a platform dependent drop site
*/
public void dragEnter(DragSourceDragEvent dsde) {
System.out.println("[Source] dragEnter");
changeCursor(
dsde.getDragSourceContext(),
dsde.getUserAction() & dsde.getDropAction()
);
}
/**
* as the hotspot moves over a platform dependent drop site
*/
public void dragOver(DragSourceDragEvent dsde) {
System.out.println("[Source] dragOver");
changeCursor(
dsde.getDragSourceContext(),
dsde.getUserAction() & dsde.getDropAction()
);
dropAction = dsde.getUserAction() & dsde.getDropAction();
System.out.println("dropAction = " + dropAction);
}
/**
* as the hotspot exits a platform dependent drop site
*/
public void dragExit(DragSourceEvent dse) {
System.out.println("[Source] dragExit");
changeCursor(
dse.getDragSourceContext(),
DnDConstants.ACTION_NONE
);
}
/**
* as the operation changes
*/
public void dragGestureChanged(DragSourceDragEvent dsde) {
System.out.println("[Source] dragGestureChanged");
changeCursor(
dsde.getDragSourceContext(),
dsde.getUserAction() & dsde.getDropAction()
);
dropAction = dsde.getUserAction() & dsde.getDropAction();
System.out.println("dropAction = " + dropAction);
}
/**
* as the operation completes
*/
public void dragDropEnd(DragSourceDropEvent dsde) {
System.out.println("[Source] dragDropEnd");
}
public void dropActionChanged(DragSourceDragEvent dsde) {
System.out.println("[Source] dropActionChanged");
dropAction = dsde.getUserAction() & dsde.getDropAction();
System.out.println("dropAction = " + dropAction);
}
public DataFlavor[] getTransferDataFlavors() {
return new DataFlavor[]{df};
}
public boolean isDataFlavorSupported(DataFlavor sdf) {
return df.equals(sdf);
}
public Object getTransferData(DataFlavor tdf) throws UnsupportedFlavorException, IOException {
Object copy = null;
if( !df.equals(tdf) ){
throw new UnsupportedFlavorException(tdf);
}
Container parent = getParent();
switch (dropAction) {
case DnDConstants.ACTION_COPY:
try {
copy = this.clone();
} catch (CloneNotSupportedException e) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(this);
ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
ObjectInputStream ois = new ObjectInputStream(bais);
try {
copy = ois.readObject();
} catch (ClassNotFoundException cnfe) {
// do nothing
}
}
parent.add(this);
return copy;
case DnDConstants.ACTION_MOVE:
synchronized (this) {
if (parent != null) {
parent.remove(this);
Label label = new Label("[empty]");
label.setBackground(Color.cyan);
label.setBounds(this.getBounds());
parent.add(label);
}
}
return this;
case DnDConstants.ACTION_LINK:
return this;
default:
return null;
}
}
}
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