I need help at adding a empty row to my JTable. I use a AbstractTableModel for my JTable! I have here a small executable program for you so it is easier to help me.
Main Class - TestClass.java
package testproject;
import java.awt.event.ActionEvent;
import java.util.ArrayList;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JTable;
public class TestClass {
String[] header = {"Name", "Quantity"};
ArrayList<Object[]> data = new ArrayList<Object[]>();
public TestClass() {
data.add(new Object[]{"Apple", "234"});
data.add(new Object[]{"Banana", "123"});
data.add(new Object[]{"Cranberry", "346"});
JFrame frame = new JFrame();
JTable table = new JTable(new Model(data, header));
JMenuBar menubar = new JMenuBar();
JMenu editmenu = new JMenu("Edit");
Action addrowaction = new AbstractAction("Add Row") {
private static final long serialVersionUID = 1433684360133156145L;
@Override
public void actionPerformed(ActionEvent e) {
data.add(new Object[9]);
}
};
frame.add(table);
frame.setJMenuBar(menubar);
menubar.add(editmenu);
editmenu.add(addrowaction);
frame.setLocationByPlatform(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.pack();
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
new TestClass();
}
});
}
}
Table Model - Model.java
package testproject;
import java.util.ArrayList;
import javax.swing.table.AbstractTableModel;
public class Model extends AbstractTableModel{
private static final long serialVersionUID = 6889542282067432083L;
private String[] header;
private ArrayList<Object[]> data;
public Model(ArrayList<Object[]> data, String[] header) {
this.header = header;
this.data = data;
}
@Override
public int getColumnCount() {
return header.length;
}
@Override
public String getColumnName(int column) {
return header[column];
}
@Override
public int getRowCount() {
return data.size();
}
@Override
public Object getValueAt(int row, int column) {
return data.get(row)[column];
}
@Override
public void setValueAt(Object value, int row, int column) {
data.get(row)[column] = value;
fireTableCellUpdated(row, column);
}
}
Basically I want to use a Action in the edit menu to add a empty row. Please do not answer with other links! I searched for it but don't understand it or it isnt suitable for my program!
EDIT: Updated the source as suggested by MadProgrammer! There is only one problem left. How I update the JTable so the new Row is displayed at the moment I have to resize the Window and the Table is updating!
As @MadProgrammer comments, arrays are conceptually easy to understand but hard to expand & contract. Instead, use a Collection
. In this example, MyModel
manages a List<Row>
that is implemented as an ArrayList<Row>
. Each Row
is a Plain Old Java Object (POJO) having an attribute for each column. Try adding a method to insert new rows using the constructor as an example, then try adding a column to Row
. The example uses a static nested class to avoid clutter.