Saturday 1 April 2017

Image Drag and Drop in java

import java.awt.FlowLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.TransferHandler;


public class IconDnD extends JFrame {


    public IconDnD() {

        setTitle("Icon Drag & Drop");

        JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT, 50, 15));

        ImageIcon icon1 = new ImageIcon("laf.png");
        ImageIcon icon2 = new ImageIcon("sad.png");
        ImageIcon icon3 = new ImageIcon("plain.png");

        JButton button = new JButton(icon2);
        button.setFocusable(false);

        JLabel label1  = new JLabel(icon1, JLabel.CENTER);
        JLabel label2  = new JLabel(icon3, JLabel.CENTER);

        MouseListener listener = new DragMouseAdapter();
        label1.addMouseListener(listener);
        label2.addMouseListener(listener);

        label1.setTransferHandler(new TransferHandler("icon"));
        button.setTransferHandler(new TransferHandler("icon"));
        label2.setTransferHandler(new TransferHandler("icon"));

        panel.add(label1);
        panel.add(button);
        panel.add(label2);
        add(panel);

        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    class DragMouseAdapter extends MouseAdapter {
        public void mousePressed(MouseEvent e) {
            JComponent c = (JComponent) e.getSource();
            TransferHandler handler = c.getTransferHandler();
            handler.exportAsDrag(c, e, TransferHandler.COPY);
        }
    }

    public static void main(String[] args) {
        new IconDnD();
    }
}



Color Drag and Drop Example in java

import java.awt.Color;
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.datatransfer.DataFlavor;
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.DropTarget;
import java.awt.dnd.DropTargetAdapter;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JColorChooser;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class ComplexExample extends JFrame
    implements DragGestureListener {

    JPanel panel;
    JPanel left;

    public ComplexExample() {

        setTitle("Complex Example");

        panel  = new JPanel(new FlowLayout(FlowLayout.LEFT, 50, 15));

        JButton openb = new JButton("Choose Color");
        openb.setFocusable(false);

        left = new JPanel();
        left.setBackground(Color.red);
        left.setPreferredSize(new Dimension(100, 100));

        openb.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                JColorChooser clr = new JColorChooser();
                Color color = clr.showDialog(panel, "Choose Color", Color.white);
                left.setBackground(color);
            }
        });

        JPanel right = new JPanel();
        right.setBackground(Color.white);
        right.setPreferredSize(new Dimension(100, 100));

        new MyDropTargetListener(right);

        DragSource ds = new DragSource();
        ds.createDefaultDragGestureRecognizer(left,
            DnDConstants.ACTION_COPY, this);

        panel.add(openb);
        panel.add(left);
        panel.add(right);
        add(panel);

        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public void dragGestureRecognized(DragGestureEvent event) {
        Cursor cursor = null;
        JPanel panel = (JPanel) event.getComponent();

        Color color = panel.getBackground();

        if (event.getDragAction() == DnDConstants.ACTION_COPY) {
            cursor = DragSource.DefaultCopyDrop;
        }

        event.startDrag(cursor, new TransferableColor(color));
    }

    class MyDropTargetListener extends DropTargetAdapter {

        private DropTarget dropTarget;
        private JPanel panel;

     public MyDropTargetListener(JPanel panel) {
        this.panel = panel;

        dropTarget = new DropTarget(panel, DnDConstants.ACTION_COPY,
            this, true, null);
      }


      public void drop(DropTargetDropEvent event) {
        try {

          Transferable tr = event.getTransferable();
          Color color = (Color) tr.getTransferData(TransferableColor.colorFlavor);

            if (event.isDataFlavorSupported(TransferableColor.colorFlavor)) {

              event.acceptDrop(DnDConstants.ACTION_COPY);
              this.panel.setBackground(color);
              event.dropComplete(true);
              return;
            }
          event.rejectDrop();
        } catch (Exception e) {
          e.printStackTrace();
          event.rejectDrop();
        }
      }
    }

    public static void main(String[] args) {
        new ComplexExample();
    }
}


class TransferableColor implements Transferable {

    protected static DataFlavor colorFlavor =
        new DataFlavor(Color.class, "A Color Object");

    protected static DataFlavor[] supportedFlavors = {
        colorFlavor,
        DataFlavor.stringFlavor,
    };

    Color color;

    public TransferableColor(Color color) { this.color = color; }

    public DataFlavor[] getTransferDataFlavors() { return supportedFlavors; }

    public boolean isDataFlavorSupported(DataFlavor flavor) {
    if (flavor.equals(colorFlavor) ||
        flavor.equals(DataFlavor.stringFlavor)) return true;
    return false;
  }


   public Object getTransferData(DataFlavor flavor)
        throws UnsupportedFlavorException
   {
     if (flavor.equals(colorFlavor))
         return color;
     else if (flavor.equals(DataFlavor.stringFlavor))
         return color.toString();
     else
         throw new UnsupportedFlavorException(flavor);
   }
}



List Drag and Drop in java

import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;

import javax.swing.DefaultListModel;
import javax.swing.DropMode;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;
import javax.swing.TransferHandler;


public class ListDrop extends JFrame {

    JTextField field;
    DefaultListModel model;

    public ListDrop() {

        setTitle("ListDrop");

        JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT, 15, 15));

        JScrollPane pane = new JScrollPane();
        pane.setPreferredSize(new Dimension(180, 150));

        model = new DefaultListModel();
        JList list = new JList(model);

        list.setDropMode(DropMode.INSERT);
        list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        list.setTransferHandler(new ListHandler());

        field = new JTextField("");
        field.setPreferredSize(new Dimension(150, 25));
        field.setDragEnabled(true);

        panel.add(field);
        pane.getViewport().add(list);
        panel.add(pane);

        add(panel);

        pack();

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }


    private class ListHandler extends TransferHandler {
        public boolean canImport(TransferSupport support) {
             if (!support.isDrop()) {
                 return false;
             }

             return support.isDataFlavorSupported(DataFlavor.stringFlavor);
         }

         public boolean importData(TransferSupport support) {
             if (!canImport(support)) {
               return false;
             }

             Transferable transferable = support.getTransferable();
             String line;
             try {
               line = (String) transferable.getTransferData(DataFlavor.stringFlavor);
             } catch (Exception e) {
               return false;
             }

             JList.DropLocation dl = (JList.DropLocation) support.getDropLocation();
             int index = dl.getIndex();

             String[] data = line.split(",");
             for (String item: data) {
                 if (!item.isEmpty())
                    model.add(index++, item.trim());
             }
             return true;
         }
    }

    public static void main(String[] args) {
        new ListDrop();
    }
}


Text Drag and Drop

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.TransferHandler;


public class SimpleDnD extends JFrame {

    JTextField field;
    JButton button;

    public SimpleDnD() {

        setTitle("Simple Drag & Drop");

        setLayout(null);

        button = new JButton("Button");
        button.setBounds(200, 50, 90, 25);

        field = new JTextField();
        field.setBounds(30, 50, 150, 25);

        add(button);
        add(field);

        field.setDragEnabled(true);
        button.setTransferHandler(new TransferHandler("text"));

        setSize(330, 150);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public static void main(String[] args) {
        new SimpleDnD();
    }
}