import java.awt.BorderLayout;
import java.awt.Rectangle;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.DefaultListModel;
import javax.swing.DropMode;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.TransferHandler;
public class DropModeON_OR_INSERT {
public static void main(String[] args) {
JPanel north = new JPanel();
north.add(new JLabel("Drag from here:"));
JTextField field = new JTextField(10);
field.setDragEnabled(true);
north.add(field);
final DefaultListModel listModel = new DefaultListModel();
listModel.addElement("first");
listModel.addElement("second");
final JList list = new JList(listModel);
list.setDragEnabled(true);
list.setTransferHandler(new TransferHandler() {
public boolean canImport(TransferHandler.TransferSupport support) {
if (!support.isDataFlavorSupported(DataFlavor.stringFlavor)) {
return false;
}
JList.DropLocation dl = (JList.DropLocation) support.getDropLocation();
if (dl.getIndex() == -1) {
return false;
} else {
return true;
}
}
public boolean importData(TransferHandler.TransferSupport support) {
if (!canImport(support)) {
return false;
}
Transferable transferable = support.getTransferable();
String data;
try {
data = (String) transferable.getTransferData(DataFlavor.stringFlavor);
} catch (Exception e) {
return false;
}
JList.DropLocation dl = (JList.DropLocation) support.getDropLocation();
int index = dl.getIndex();
if (dl.isInsert()) {
listModel.add(index, data);
} else {
listModel.set(index, data);
}
// Scroll to display the element that was dropped
Rectangle r = list.getCellBounds(index, index);
list.scrollRectToVisible(r);
return true;
}
});
JScrollPane center = new JScrollPane();
center.setViewportView(list);
list.setDropMode(DropMode.ON_OR_INSERT);
JPanel cp = new JPanel();
cp.setLayout(new BorderLayout());
cp.add(north, BorderLayout.NORTH);
cp.add(center, BorderLayout.CENTER);
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(cp);
frame.pack();
frame.setVisible(true);
}
}