how to perform drag and drop from JFileChooser to JList containig Folders

Question

I have design a frame in which i have used JFileChooser and JList. now i want to perform drag and drop feature from JfileChooser to JList contianing Folder (Such as in my screen Short JList contians folder name a,b,c) suppose from JFileChooser i open a folder and from this folder i select (example.txt)file and then i perform drag and drop of this to JList contianing folder a. so i want (example.txt) file should be in folder a.

how to do this things.and i have one more problem. in my screenshot Jlist contian Three folder(a,b,c).
so when i click on folder a but i m not able to get inside folder a.

this is my code by using this i have create screenshot.

In this code i have create JFileChooser and JList. I have add all the folder into the JList. now i want to perform Drag and Drop from JFileChooser to JList containing folder.

this is my code by using this i have create screenshot. In this code i have create JFileChooser and JList. I have add all the folder into the JList. now i want to perform Drag and Drop from JFileChooser to JList containing folder.

    package com.dhananjaynet.swing;

import java.awt.datatransfer.*;
import java.awt.event.*;
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.io.*;
import javax.swing.*;
import javax.swing.UIManager.LookAndFeelInfo;
import javax.swing.border.TitledBorder;
import javax.swing.filechooser.FileNameExtensionFilter;
import javax.swing.filechooser.FileSystemView;
import javax.swing.text.*;

import com.dhananjay.swing.upload.ReadAllFolderName;

import java.util.ArrayList;
import java.util.List;


public class ConsolidatorDemo extends JPanel implements ActionListener {
    private static final long serialVersionUID = -4487732343062917781L;
    JFileChooser fc;
    JButton clear;
    JTextArea console;

    JList dropZone;
    DefaultListModel listModel;
    JSplitPane childSplitPane, parentSplitPane;
    PrintStream ps;
    ArrayList<String > directyName;

  public ConsolidatorDemo() {

    super(new BorderLayout());

    fc = new JFileChooser();

    fc.setMultiSelectionEnabled(true);
    fc.setDragEnabled(true);
    fc.setControlButtonsAreShown(false);
    fc.setFileSelectionMode(JFileChooser.FILES_ONLY);


    JPanel fcPanel = new JPanel(new BorderLayout());
    fcPanel.add(fc, BorderLayout.CENTER);

    clear = new JButton("Clear All");

    clear.addActionListener(this);

    JPanel buttonPanel = new JPanel(new BorderLayout());

    buttonPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));

    buttonPanel.add(clear, BorderLayout.LINE_END);


    JPanel leftUpperPanel = new JPanel(new BorderLayout());

    leftUpperPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));

    leftUpperPanel.add(fcPanel, BorderLayout.CENTER);

    leftUpperPanel.add(buttonPanel, BorderLayout.PAGE_END);

    JScrollPane leftLowerPanel = new javax.swing.JScrollPane();

    leftLowerPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));

    listModel = new DefaultListModel();

    directyName=ReadAllFolderName.ReadDirectory();

    dropZone = new JList(listModel);

    dropZone.setListData(directyName.toArray());

    dropZone.setCellRenderer(new FileCellRenderer());

    dropZone.setTransferHandler(new ListTransferHandler(dropZone));

    dropZone.setDragEnabled(true);

    dropZone.setDropMode(javax.swing.DropMode.INSERT);
    dropZone.setBorder(new TitledBorder("Selected files/folders"));
    leftLowerPanel.setViewportView(new JScrollPane(dropZone));

    childSplitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT,
            leftUpperPanel, leftLowerPanel);
    childSplitPane.setDividerLocation(400);
    childSplitPane.setPreferredSize(new Dimension(480, 650));

    console = new JTextArea();
    console.setColumns(40);
    console.setLineWrap(true);
    console.setBorder(new TitledBorder("Console"));

    parentSplitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,
                    childSplitPane, console);
    parentSplitPane.setDividerLocation(480);
    parentSplitPane.setPreferredSize(new Dimension(800, 650));

    add(parentSplitPane, BorderLayout.CENTER);

}

public void setDefaultButton() {
    getRootPane().setDefaultButton(clear);
}

public void actionPerformed(ActionEvent e) {
    if (e.getSource() == clear) {
        listModel.clear();
    }
}


/**
 * Create the GUI and show it. For thread safety,
 * this method should be invoked from the
 * event-dispatching thread.![this is my GUI][2]
 */


private static void createAndShowGUI() {

    //Make sure we have nice window decorations.
    JFrame.setDefaultLookAndFeelDecorated(true);
    try {

      //UIManager.setLookAndFeel("de.javasoft.plaf.synthetica.SyntheticaBlackStarLookAndFeel");
        for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    }catch (Exception e){
      e.printStackTrace();
    }

    //Create and set up the window.
    JFrame frame = new JFrame("Consolidator!");
    frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

    //Create and set up the menu bar and content pane.
    ConsolidatorDemo demo = new ConsolidatorDemo();
    demo.setOpaque(true); //content panes must be opaque
    frame.setContentPane(demo);

    //Display the window.
    frame.pack();
    frame.setVisible(true);
    demo.setDefaultButton();
}

public static void main(String[] args) {

    //Schedule a job for the event-dispatching thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}
}

class FileCellRenderer extends DefaultListCellRenderer {

    public Component getListCellRendererComponent(JList list,
        Object value,
        int index,
        boolean isSelected,
        boolean cellHasFocus) {

        Component c = super.getListCellRendererComponent(
            list,value,index,isSelected,cellHasFocus);

        if (c instanceof JLabel && value instanceof File) {
            JLabel l = (JLabel)c;
            File f = (File)value;
            l.setIcon(FileSystemView.getFileSystemView().getSystemIcon(f));
            l.setText(f.getName());
            l.setToolTipText(f.getAbsolutePath());
        }

        return c;
    }
}

class ListTransferHandler extends TransferHandler {

    private JList list;

    ListTransferHandler(JList list) {
        this.list = list;
    }

    @Override
    public boolean canImport(TransferHandler.TransferSupport info) {
        // we only import FileList
        if (!info.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
            return false;
        }
        return true;
    }

    @Override
    public boolean importData(TransferHandler.TransferSupport info) {
        if (!info.isDrop()) {
            return false;
        }

        // Check for FileList flavor
        if (!info.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
            displayDropLocation("List doesn't accept a drop of this type.");
            return false;
        }

        // Get the fileList that is being dropped.
        Transferable t = info.getTransferable();
        List<File> data;
        try {
            data = (List<File>)t.getTransferData(DataFlavor.javaFileListFlavor);
        }
        catch (Exception e) { return false; }
        DefaultListModel model = (DefaultListModel) list.getModel();
        for (Object file : data) {
            model.addElement((File)file);
        }
        return true;
    }

    private void displayDropLocation(String string) {
        System.out.println(string);
    }
}

 this my other class for Populating all the folder name into JList


package com.dhananjay.swing.upload;

import java.io.File;
import java.util.ArrayList;

public class ReadAllFolderName {


    public static ArrayList<String> ReadDirectory() {
        String path = "C:\\Users\\SonyBastian\\Desktop\\DMC";

        ArrayList<String> files = new ArrayList<String>();
        File folder = new File(path);
        File[] listOfFiles = folder.listFiles();

        for (int i = 0; i < listOfFiles.length; i++) {
            System.out.println("method 1");
            if (listOfFiles[i].isDirectory()) {

                files.add(listOfFiles[i].getName());
                /*if (files.endsWith(".txt") || files.endsWith(".TXT")) {
                    System.out.println(files);
                }*/
            }
        }
        return files;
    }
}

![enter image description here][3]


  [1]: https://i.sstatic.net/YAP60.png

Thanks

Answer 1

You have problems with JList model, you create it with DefaultListModel, but then you use dropZone.setListData(directyName.toArray()); which recreate model, because of you get Exception at next line DefaultListModel model = (DefaultListModel) list.getModel();.

So, try to create and populate JList like next:

directyName=ReadAllFolderName.ReadDirectory();
listModel = new DefaultListModel();
for(String s : directyName){
    listModel.addElement(s);
}
dropZone = new JList(listModel);