import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DragGestureEvent;
import java.awt.dnd.DragGestureListener;
import java.awt.dnd.DragSource;
import java.awt.dnd.DragSourceContext;
import java.awt.dnd.DragSourceDragEvent;
import java.awt.dnd.DragSourceDropEvent;
import java.awt.dnd.DragSourceEvent;
import java.awt.dnd.DragSourceListener;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.awt.dnd.InvalidDnDOperationException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class MainClass extends JFrame implements ActionListener, DropTargetListener {
DragLabel source = new DragLabel("Drag and drop me to the following JButton", JLabel.CENTER);
JButton target = new JButton();
MainClass(String title) {
super(title);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
source.setForeground(Color.red);
getContentPane().add(source, BorderLayout.NORTH);
target.addActionListener(this);
getContentPane().add(target, BorderLayout.SOUTH);
new DropTarget(target, DnDConstants.ACTION_COPY_OR_MOVE, this);
setSize(205, 100);
setVisible(true);
}
public void actionPerformed(ActionEvent e) {
JButton b = (JButton) e.getSource();
b.setText("");
source.setText("Drag and drop me to the following JButton");
}
public void dragEnter(DropTargetDragEvent e) {
System.out.println("Entering drop target #1");
}
public void dragExit(DropTargetEvent e) {
System.out.println("Exiting drop target #1");
}
public void dragOver(DropTargetDragEvent e) {
System.out.println("Dragging over drop target #1");
}
public void drop(DropTargetDropEvent e) {
System.out.println("Dropping");
try {
Transferable t = e.getTransferable();
if (e.isDataFlavorSupported(DataFlavor.stringFlavor)) {
e.acceptDrop(e.getDropAction());
String s;
s = (String) t.getTransferData(DataFlavor.stringFlavor);
target.setText(s);
e.dropComplete(true);
} else
e.rejectDrop();
} catch (java.io.IOException e2) {
} catch (UnsupportedFlavorException e2) {
}
}
public void dropActionChanged(DropTargetDragEvent e) {
System.out.println("Drop action changed #1");
}
public static void main(String[] args) {
new MainClass("Drag and Drop Demo");
}
}
class DragLabel extends JLabel implements DragGestureListener, DragSourceListener {
private DragSource ds = DragSource.getDefaultDragSource();
public DragLabel(String s, int alignment) {
super(s, alignment);
int action = DnDConstants.ACTION_COPY_OR_MOVE;
ds.createDefaultDragGestureRecognizer(this, action, this);
}
public void dragGestureRecognized(DragGestureEvent e) {
try {
Transferable t = new StringSelection(getText());
e.startDrag(DragSource.DefaultCopyNoDrop, t, this);
} catch (InvalidDnDOperationException e2) {
System.out.println(e2);
}
}
public void dragDropEnd(DragSourceDropEvent e) {
System.out.println("Drag and drop end");
if (e.getDropSuccess() == false) {
System.out.println("unsuccessful");
return;
}
int action = e.getDropAction();
if ((action & DnDConstants.ACTION_MOVE) != 0)
setText("");
}
public void dragEnter(DragSourceDragEvent e) {
System.out.println("Entering drop target #2");
DragSourceContext ctx = e.getDragSourceContext();
int action = e.getDropAction();
if ((action & DnDConstants.ACTION_COPY) != 0)
ctx.setCursor(DragSource.DefaultCopyDrop);
else
ctx.setCursor(DragSource.DefaultCopyNoDrop);
}
public void dragExit(DragSourceEvent e) {
System.out.println("Exiting drop target #2");
}
public void dragOver(DragSourceDragEvent e) {
System.out.println("Dragging over drop target #2");
}
public void dropActionChanged(DragSourceDragEvent e) {
System.out.println("Drop action changed #2");
}
}
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