/*
* Copyright (c) 2009, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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.image.ImageConsumer;
import java.awt.image.MemoryImageSource;
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
*/
int iProblem = 0;
String[] problem = {"unready", "throw exeption", "good"};
public void dragGestureRecognized(DragGestureEvent dge) {
System.out.println("starting Drag");
if( !DragSource.isDragImageSupported() ) {
dge.startDrag(
null,
this,
this);
} else {
setLabel("Drag ME! (with " + problem[iProblem] + " image)");
int w = 100;
int h = 100;
int pix[] = new int[w * h];
int index = 0;
for (int y = 0; y < h; y++) {
int red = (y * 255) / (h - 1);
for (int x = 0; x < w; x++) {
int blue = (x * 255) / (w - 1);
pix[index++] = (255 << 24) | (red << 16) | blue;
}
}
try{
dge.startDrag(
null,
Toolkit.getDefaultToolkit().createImage(new MemoryImageSource(w, h, pix, 0, w)
{
@Override
public void startProduction(ImageConsumer ic)
{
switch(iProblem){
case 0:
//incomplite
break;
case 1:
//exception
throw new RuntimeException("test exception 1");
default:
super.startProduction(ic);
break;
}
}
}
),
new Point(15, 40) {
@Override
public double getX() {
if(2==iProblem){
//never happen
throw new RuntimeException("test exception 2");
}
return x;
}
@Override
public Point getLocation(){
//never happen
throw new RuntimeException("test exception 3");
}
},
this,
this);
}catch(InvalidDnDOperationException e){
if( iProblem<=2 ){
System.err.println("good exception: " + e.getMessage() );
} else {
System.err.println("bad exception");
e.printStackTrace();
throw new RuntimeException(e.getMessage());
}
} finally {
++iProblem;
}
}
}
/**
* 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;
}
}
}