Drag and Drop in a JTable (ContentTable)

Here's an example of drag and drop of a cell in JTable.

You can move or copy (using Ctrl) a cell to another location:

import java.awt.BorderLayout;

import java.awt.Dimension;

import java.awt.GridLayout;

import java.awt.datatransfer.DataFlavor;

import java.awt.datatransfer.StringSelection;

import java.awt.datatransfer.Transferable;

import java.awt.datatransfer.UnsupportedFlavorException;

import java.io.IOException;

import javax.swing.BorderFactory;

import javax.swing.JComponent;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.JTable;

import javax.swing.ListSelectionModel;

import javax.swing.TransferHandler;

import javax.swing.table.DefaultTableModel;

public class DnD_Demo extends JFrame {

public DnD_Demo() {

setTitle("DnD Demo (Version 3)");

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

JPanel panel = new JPanel(new GridLayout(1,1));

panel.add(createTable("Table A"));

getContentPane().add(panel,BorderLayout.CENTER);

pack();

}

private JPanel createTable(String tableId) {

DefaultTableModel model = new DefaultTableModel();

model.addColumn("Column 0");

model.addColumn("Column 1");

model.addColumn("Column 2");

model.addColumn("Column 3");

model.addRow(new String[]{tableId+" 00", tableId+" 01", tableId+" 02", tableId+" 03"});

model.addRow(new String[]{tableId+" 10", tableId+" 11", tableId+" 12", tableId+" 13"});

model.addRow(new String[]{tableId+" 20", tableId+" 21", tableId+" 22", tableId+" 23"});

model.addRow(new String[]{tableId+" 30", tableId+" 31", tableId+" 32", tableId+" 33"});

JTable table = new JTable(model);

table.getTableHeader().setReorderingAllowed(false);

table.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);

JScrollPane scrollPane = new JScrollPane(table);

scrollPane.setPreferredSize(new Dimension(400,100));

table.setDragEnabled(true);

table.setTransferHandler(new TableTransferHandler());

JPanel panel = new JPanel();

panel.add(scrollPane);

panel.setBorder(BorderFactory.createTitledBorder(tableId));

return panel;

}

public static void main(String[] args) {

new DnD_Demo().setVisible(true);

}

abstract class StringTransferHandler extends TransferHandler {

protected abstract String exportString(JComponent c);

protected abstract void importString(JComponent c, String str);

protected abstract void cleanup(JComponent c, boolean remove);

protected Transferable createTransferable(JComponent c) {

return new StringSelection(exportString(c));

}

public int getSourceActions(JComponent c) {

return COPY_OR_MOVE;

}

public boolean importData(JComponent c, Transferable t) {

if (canImport(c, t.getTransferDataFlavors())) {

try {

String str = (String)t.getTransferData(DataFlavor.stringFlavor);

importString(c, str);

return true;

} catch (UnsupportedFlavorException ufe) {

} catch (IOException ioe) {

}

}

return false;

}

protected void exportDone(JComponent c, Transferable data, int action) {

cleanup(c, action == MOVE);

}

public boolean canImport(JComponent c, DataFlavor[] flavors) {

for (int i = 0; i < flavors.length; i++) {

if (DataFlavor.stringFlavor.equals(flavors[i])) {

return true;

}

}

return false;

}

}

class TableTransferHandler extends StringTransferHandler {

public JTable target;

public int row = -1;

public int col = -1;

protected String exportString(JComponent c) {

JTable table = (JTable)c;

row = table.getSelectedRow();

col = table.getSelectedColumn();

return table.getValueAt(row, col).toString();

}

protected void importString(JComponent c, String str) {

target = (JTable)c;

int row = target.getSelectedRow();

int col = target.getSelectedColumn();

target.getModel().setValueAt(str, row, col);

}

protected void cleanup(JComponent c, boolean remove) {

JTable table = (JTable)c;

if (remove)

table.getModel().setValueAt("", row, col);

}

}

}

Message was edited by:

Rodney_McKay

Rodney_McKaya at 2007-7-10 11:36:30 >

This means that :

1. There may be 1 or more tasks on a particular day/time. When we drag and drop that should be appended to the next time/day and nothing should be erased here.

2. I am using "Expand" checkbox wherein when user clicks on it the cells will show the tasks with details else only number of tasks are shown.

Kindly help me to resolve the problem with your ideas..

Thanks and Rgds,

Pradeep

KINOa at 2007-7-10 11:36:30 >

> This works as I have a Vector for storing the text in multiline(Cell) JTable

Then you need to customize the import/export code. The export will need to create a text string delimited by some character. Then the import will need to parse this string and create the Vectore before storing it in your TableModel.

camickra at 2007-7-10 11:36:30 >