Cell contents selected on focus in JTable

Question

I'm new to swing and trying to get the contents of a JTable cell to be selected when the cell receives focus. I've looked at the TableCellEditor interface and the like, but I just can't seem to get the hang of how it all fits together. Any hits would be appreciated. Thanks.

Answer 1

There are several ways to do this, but here is one to get you started:
First, subclass DefaultCellEditor. Here, I have duplicated all the constructors from DefaultCellEditor but only modified the one used for text.
I have added a inner class, FocusEventHandler, to capture the focus events. In the focusGained method is the code to do the selectAll. (I use the invokeLater so that the selectAll happens after pending events are complete. A mouse click might be interpreted by the text box to position the cursor, so we want the selectAll to happen after that.)
Then, in the constructor for text, I save the text box so the focusGained method knows which text box to selectAll for, register the event handler, and (optionally) change the ClickCountToStart.
public class NewDefaultCellEditor extends javax.swing.DefaultCellEditor {
javax.swing.JTextField saveTextField = null;
// Event handler
public class FocusEventHandler implements java.awt.event.FocusListener {
     public void focusGained(java.awt.event.FocusEvent e) {
          javax.swing.SwingUtilities.invokeLater(new Runnable () {public void run() {saveTextField.selectAll();}});
     public void focusLost(java.awt.event.FocusEvent e) {}
// Constructors
public NewDefaultCellEditor(javax.swing.JCheckBox checkBox) {
     super(checkBox);
public NewDefaultCellEditor(javax.swing.JComboBox comboBox) {
     super(comboBox);
public NewDefaultCellEditor(javax.swing.JTextField textField) {
     super(textField);
     saveTextField = textField; // save text field for later
     textField.addFocusListener(new FocusEventHandler()); // register event handler
     setClickCountToStart(1); // change # of mouse clicks to begin editing
}Now you just have to tell the table to use this Cell Editor. One way to do this is:
MyTable.getColumnModel().getColumn(0).setCellEditor(new NewDefaultCellEditor(new javax.swing.JTextField()));
(this sets the editor for column 0)