Drag & Drop of a file not working in Ubuntu & other linux

Question

Hi All,
I am working on a project,in which it has the requirement of dragging the files
from a JList present inside a JFrame to the desktop.
First I tried to get a solution using dnd API but could not. Then i googled and i got an application which is
working perfectly in both Windows and MAC Operating systems, after I made few minor changes to suit my requirements.
Below is the URL of that application:
http://stackoverflow.com/questions/1204580/swing-application-drag-drop-to-the-desktop-folder
The problem is the same application when I executed on Ubuntu, its not working at all. I tried all available options but could not trace out the exact reason.
Can anybody help me to overcome this issue?
Thanks in advance

Answer 1

Hi,
With the information you provided and through some information found on google i coded an application. This application is able to do the drag and drop of an item from the Desktop to Java application on Linux Platform, but i am unble to do the viceversa by this application.
I am including the application and the URL of the information i got.
[URL Of Information Found|http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4899516]
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
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.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.swing.DefaultListModel;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
import javax.swing.TransferHandler;
import javax.swing.WindowConstants;
public class DnDFrame extends JFrame implements DropTargetListener {
     private DefaultListModel listModel = new DefaultListModel();
     private DropTarget dropTarget;
     private JLabel jLabel1;
     private JScrollPane jScrollPane1;
     private JList list;
     List<File> files;
     /** Creates new form DnDFrame */
     public DnDFrame() {
          setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          initComponents();
          dropTarget = new DropTarget(list, this);
          list.setModel(listModel);
          list.setDragEnabled(true);
          list.setTransferHandler(new FileTransferHandler());
     @SuppressWarnings("unchecked")
     private void initComponents() {
          GridBagConstraints gridBagConstraints;
          jLabel1 = new JLabel();
          jScrollPane1 = new JScrollPane();
          list = new JList();
          setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
          getContentPane().setLayout(new GridBagLayout());
          jLabel1.setText("Files:");
          gridBagConstraints = new GridBagConstraints();
          gridBagConstraints.gridwidth = GridBagConstraints.REMAINDER;
          gridBagConstraints.anchor = GridBagConstraints.WEST;
          getContentPane().add(jLabel1, gridBagConstraints);
          jScrollPane1.setViewportView(list);
          gridBagConstraints = new GridBagConstraints();
          gridBagConstraints.gridwidth = GridBagConstraints.REMAINDER;
          gridBagConstraints.fill = GridBagConstraints.HORIZONTAL;
          getContentPane().add(jScrollPane1, gridBagConstraints);
          pack();
     public void dragEnter(DropTargetDragEvent arg0) {
     public void dragOver(DropTargetDragEvent arg0) {
     public void dropActionChanged(DropTargetDragEvent arg0) {
     public void dragExit(DropTargetEvent arg0) {
     public void drop(DropTargetDropEvent evt) {
          System.out.println(evt);
          int action = evt.getDropAction();
          evt.acceptDrop(action);
          try {
               Transferable data = evt.getTransferable();
               DataFlavor uriListFlavor = null;
               try {
                    uriListFlavor = new DataFlavor("text/uri-list;class=java.lang.String");
               } catch (ClassNotFoundException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
               System.out.println("data.isDataFlavorSupported(DataFlavor.javaFileListFlavor: " +
                         data.isDataFlavorSupported(DataFlavor.javaFileListFlavor) );
               if (data.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
                    files = (List<File>) data.getTransferData(DataFlavor.javaFileListFlavor);
                    for (File file : files) {
                         listModel.addElement(file);
               }else if (data.isDataFlavorSupported(uriListFlavor)) {
                    String data1 = (String)data.getTransferData(uriListFlavor);
                    files = (List<File>) textURIListToFileList(data1);
                    for (File file : files) {
                         listModel.addElement(file);
                    System.out.println(textURIListToFileList(data1));
          } catch (UnsupportedFlavorException e) {
               e.printStackTrace();
          } catch (IOException e) {
               e.printStackTrace();
          } finally {
               evt.dropComplete(true);
     private static java.util.List textURIListToFileList(String data) {
          java.util.List list = new java.util.ArrayList(1);
          for (java.util.StringTokenizer st = new java.util.StringTokenizer(data,"\r\n");
          st.hasMoreTokens();) {
               String s = st.nextToken();
               if (s.startsWith("#")) {
                    continue;
               try {
                    java.net.URI uri = new java.net.URI(s);
                    java.io.File file = new java.io.File(uri);
                    list.add(file);
               } catch (java.net.URISyntaxException e) {
               } catch (IllegalArgumentException e) {
          return list;
     private class FileTransferHandler extends TransferHandler {
          @Override
          protected Transferable createTransferable(JComponent c) {
               JList list = (JList) c;
               List<File> files = new ArrayList<File>();
               for (Object obj: list.getSelectedValues()) {
                    files.add((File)obj);
               return new FileTransferable(files);
          @Override
          public int getSourceActions(JComponent c) {
               return COPY;
     static {
          try {
               uriListFlavor = new
               DataFlavor("text/uri-list;class=java.lang.String");
          } catch (ClassNotFoundException e) {
               e.printStackTrace();
     private class FileTransferable implements Transferable {
          private List<File> files;
          public FileTransferable(List<File> files) {
               this.files = files;
          public DataFlavor[] getTransferDataFlavors() {
               return new DataFlavor[]{DataFlavor.javaFileListFlavor,uriListFlavor};
          public boolean isDataFlavorSupported(DataFlavor flavor) {
               if(flavor.equals(DataFlavor.javaFileListFlavor) || flavor.equals(uriListFlavor))
                    return true;
               else
                    return false;
          public Object getTransferData(DataFlavor flavor) throws
          UnsupportedFlavorException, java.io.IOException {
                  if (isDataFlavorSupported(flavor) && flavor.equals(DataFlavor.javaFileListFlavor)) {
                    return files;
               }else if (isDataFlavorSupported(flavor) && flavor.equals(uriListFlavor)) {
                    java.io.File file = new java.io.File("file.txt");
                    String data = file.toURI() + "\r\n";
                    return data;
               }else {
                    throw new UnsupportedFlavorException(flavor);
     private static DataFlavor uriListFlavor;
     static {
          try {
               uriListFlavor = new
               DataFlavor("text/uri-list;class=java.lang.String");
          } catch (ClassNotFoundException e) {
               e.printStackTrace();
     public static void dumpProperty(String name) {
          System.out.println(name + " \t" + System.getProperty(name) );
     public static void main(String[] args) {
          String[] props = {
                    "java.version",
                    "java.vm.version",
                    "java.vendor",
                    "os.name",
          "os.version"};
          for (String prop : props) {
               dumpProperty(prop);
          Runnable r = new Runnable() {
               public void run() {
                    DnDFrame f = new DnDFrame();
                    f.setVisible(true);
          SwingUtilities.invokeLater(r);
}Please Suggest me in this.