How to keep original component after I Drag nad drop ?
Dear friends:
Good monday,
I have following code can successfully drag and drop Text string in DragLabel to JButton, but after each DnD, Original DragLabel disappear, so after DnD, nothing left at the DragLabel,
But I really hope to keep this DragLabel after DnD,
How to do it?
Thanks
package com.jdbc;
//DnDConstants.ACTION_COPY_OR_MOVE
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;
publicclass actionCopyOrMoveextends JFrameimplements ActionListener, DropTargetListener{
DragLabel source =new DragLabel("Drag and drop me to the following JButton", JLabel.CENTER);
JButton target =new JButton("My Target ");
actionCopyOrMove(String title){
super(title);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
source.setForeground(Color.red);
getContentPane().add(source, BorderLayout.NORTH);
target.addActionListener(this);
target.setSize(200, 50);
getContentPane().add(target, BorderLayout.SOUTH);
new DropTarget(target, DnDConstants.ACTION_COPY_OR_MOVE,this);
setSize(205, 100);
setVisible(true);
}
publicvoid actionPerformed(ActionEvent e){
JButton b = (JButton) e.getSource();
b.setText("");
source.setText("Drag and drop me to the following JButton");
}
publicvoid dragEnter(DropTargetDragEvent e){
System.out.println("Entering drop target #1");
}
publicvoid dragExit(DropTargetEvent e){
System.out.println("Exiting drop target #1");
}
publicvoid dragOver(DropTargetDragEvent e){
System.out.println("Dragging over drop target #1");
}
publicvoid 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){
}
}
publicvoid dropActionChanged(DropTargetDragEvent e){
System.out.println("Drop action changed #1");
}
publicstaticvoid main(String[] args){
new actionCopyOrMove("Drag and Drop Demo");
}
}
class DragLabelextends JLabelimplements 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);
}
publicvoid dragGestureRecognized(DragGestureEvent e){
try{
Transferable t =new StringSelection(getText());
e.startDrag(DragSource.DefaultCopyNoDrop, t,this);
}catch (InvalidDnDOperationException e2){
System.out.println(e2);
}
}
publicvoid 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("");
}
publicvoid 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);
}
publicvoid dragExit(DragSourceEvent e){
System.out.println("Exiting drop target #2");
}
publicvoid dragOver(DragSourceDragEvent e){
System.out.println("Dragging over drop target #2");
}
publicvoid dropActionChanged(DragSourceDragEvent e){
System.out.println("Drop action changed #2");
}
}
sunny
