Java APIs

Use ComponentListener#componentShown and wrap the requestFocus in a SwingUtilities#invokeLater to be sure of consistent behavior.

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import javax.swing.AbstractCellEditor;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.table.TableCellEditor;

public class JTableEditorTest {

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {

         public void run() {
            JFrame frame = new JFrame("Editor Test");
            frame.setBounds(20, 20, 400, 400);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setLayout(new GridLayout(1, 1));

            JTable table = new JTable(new Object[][]{{"", ""}, {"", ""}}, new Object[]{
                       "col1",
                       "col2"
                    });

            table.getColumnModel().getColumn(0).setCellEditor(new CustomComponentCellEditor(
                    new CustomComponent()));

            frame.add(new JScrollPane(table));

            frame.setVisible(true);
         }
      });
   }
}

class CustomComponent extends JComponent {

   protected JTextField textField;
   protected JButton button;

   public CustomComponent() {
      textField = new JTextField();
      button = new JButton();

      button.setPreferredSize(new Dimension(25, 25));
      textField.setPreferredSize(new Dimension(125, 25));

      this.setLayout(new BorderLayout());

      this.add(textField, BorderLayout.CENTER);
      this.add(button, BorderLayout.EAST);

      this.addComponentListener(new ComponentAdapter() {

         @Override
         public void componentShown(ComponentEvent e) {
            SwingUtilities.invokeLater(new Runnable() {

               public void run() {
                  CustomComponent.this.textField.requestFocusInWindow();
               }
            });
         }
      });
   }
}

class CustomComponentCellEditor extends AbstractCellEditor implements
        TableCellEditor {

   private CustomComponent component;

   public CustomComponentCellEditor(CustomComponent component) {
      this.component = component;
   }

   public Object getCellEditorValue() {
      return this.component.textField.getText();
   }

   public Component getTableCellEditorComponent(JTable table, Object value,
           boolean isSelected, int row, int column) {
      return this.component;
   }
}

db

Hi db

Thank you for your solution, but the problem still exists. I apologise if I was unclear in my original post. When the user starts typing while a cell is selected, but the editor isn't opened yet, I want the character typed to be passed to the editor, and the text field should be selected, with the caret just after the character passed from the table. Any ideas on how I can do that?

Below is my updated code. I have overridden isCellEditable() to insert the character into the text field (this is probably not be the best way to do it), and to check for a double click before starting editing. (I think this will make it easier to demonstrate the problem.)

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseEvent;
import java.util.EventObject;
import javax.swing.AbstractCellEditor;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.table.TableCellEditor;
 
public class JTableEditorTest {
 
   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
 
         public void run() {
            JFrame frame = new JFrame("Editor Test");
            frame.setBounds(20, 20, 400, 400);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setLayout(new GridLayout(1, 1));
 
            JTable table = new JTable(new Object[][]{{"", ""}, {"", ""}}, new Object[]{
                       "col1",
                       "col2"
                    });
 
            table.getColumnModel().getColumn(0).setCellEditor(new CustomComponentCellEditor(
                    new CustomComponent()));
 
            frame.add(new JScrollPane(table));
 
            frame.setVisible(true);
         }
      });
   }
}
 
class CustomComponent extends JComponent {
 
   protected JTextField textField;
   protected JButton button;
 
   public CustomComponent() {
      textField = new JTextField();
      button = new JButton();
 
      button.setPreferredSize(new Dimension(25, 25));
      textField.setPreferredSize(new Dimension(125, 25));
 
      this.setLayout(new BorderLayout());
 
      this.add(textField, BorderLayout.CENTER);
      this.add(button, BorderLayout.EAST);
 
      this.addComponentListener(new ComponentAdapter() {
 
         @Override
         public void componentShown(ComponentEvent e) {
            SwingUtilities.invokeLater(new Runnable() {
 
               public void run() {
                  CustomComponent.this.textField.requestFocusInWindow();
               }
            });
         }
      });
   }
}
 
class CustomComponentCellEditor extends AbstractCellEditor implements
        TableCellEditor {
 
   private CustomComponent component;
 
   public CustomComponentCellEditor(CustomComponent component) {
      this.component = component;
   }
 
   public Object getCellEditorValue() {
      return this.component.textField.getText();
   }
 
   public Component getTableCellEditorComponent(JTable table, Object value,
           boolean isSelected, int row, int column) {
      return this.component;
   }

    @Override
    public boolean isCellEditable(EventObject evt) {
        if (evt instanceof MouseEvent) {
            if (((MouseEvent)evt).getClickCount() == 2) {
                return true;
            } else {
                return false;
            }
        } else if (evt instanceof KeyEvent) {
            component.textField.setText(String.valueOf(((KeyEvent)evt).getKeyChar()));
        }
        
        return true;
    }

}

Hi
How about to use HierarchyListener:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
public class JTableEditorTest3 {
  public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        JFrame frame = new JFrame("Editor Test");
        frame.setBounds(200, 200, 400, 400);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new GridLayout(1, 1));
        JTable table = new JTable(
          new Object[][] {{"", "", ""}, {"", "", ""}},
          new Object[] {"col1", "col2", "default"});
        table.getColumnModel().getColumn(0).setCellEditor(
          new CustomComponentCellEditor());
        table.getColumnModel().getColumn(1).setCellEditor(
          new CustomComponentCellEditor2(new JTextField()));
        frame.add(new JScrollPane(table));
        frame.setVisible(true);
      }
    });
  }
}
class CustomComponentCellEditor extends AbstractCellEditor
    implements TableCellEditor {
  protected final JTextField textField;
  protected JButton button;
  private final JPanel panel = new JPanel(new BorderLayout());
  public CustomComponentCellEditor() {
    super();
    textField = new JTextField();
    button = new JButton();
    button.setPreferredSize(new Dimension(25, 25));
    textField.setBorder(BorderFactory.createEmptyBorder(0,2,0,0));
    panel.add(textField);
    panel.add(button, BorderLayout.EAST);
    textField.addHierarchyListener(new HierarchyListener() {
      public void hierarchyChanged(HierarchyEvent e) {
        if ((e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED)!=0
            && textField.isShowing()) {
          System.out.println("hierarchyChanged: SHOWING_CHANGED");
          textField.requestFocusInWindow();
        }
      }
    });
  }
  public Object getCellEditorValue() {
    System.out.println("  "+textField.getText());
    return textField.getText();
  }
  public Component getTableCellEditorComponent(JTable table, Object value,
      boolean isSelected, int row, int column) {
    return panel;
  }
  public boolean isCellEditable(java.util.EventObject evt) {
    System.out.println("isCellEditable");
    if (evt instanceof MouseEvent) {
      if (((MouseEvent)evt).getClickCount() == 2) {
        return true;
      } else {
        return false;
      }
    } else if (evt instanceof KeyEvent) {
      textField.setText(String.valueOf(((KeyEvent)evt).getKeyChar()));
    }
    return true;
  }
}
class CustomComponentCellEditor2 extends DefaultCellEditor
      implements TableCellEditor {
  protected final JButton button = new JButton();
  public CustomComponentCellEditor2(final JTextField textField) {
    super(textField);
    textField.add(button);
    textField.setBorder(BorderFactory.createEmptyBorder(0,2,0,25));
    textField.addHierarchyListener(new HierarchyListener() {
      public void hierarchyChanged(HierarchyEvent e) {
        if ((e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED)!=0
            && textField.isShowing()) {
          System.out.println("hierarchyChanged: SHOWING_CHANGED");
          Rectangle r = textField.getBounds();
          button.setBounds(r.width-25, 0, 25, r.height);
        }
      }
    });
  }
}

Nicely done, thanks!

I would like to know why you recommended the SwingUtilities#invokeLater part. Wouldn't that start an unnecessary thread? Unless my understanding of SwingUtilities#invokeLater is totally wrong.

I'll explain the invokeLater at the end of the post.

This is my upgraded attempt, with a custom editor that extends DefaultCellEditor to use its default functionality.

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.util.EventObject;
import javax.swing.DefaultCellEditor;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

public class JTableEditorTest {

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {

         public void run() {
            JFrame frame = new JFrame("Editor Test");
            frame.setBounds(20, 20, 400, 400);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setLayout(new GridLayout(1, 1));

            JTable table = new JTable(new Object[][]{{"", ""}, {"", ""}},
                    new Object[]{"col1", "col2"});

            table.getColumnModel().getColumn(0).
                    setCellEditor(new CustomComponentCellEditor(
                    new CustomComponent()));

            frame.add(new JScrollPane(table));
            frame.setVisible(true);
         }
      });
   }
}

class CustomComponent extends JComponent {

   protected JTextField textField;
   protected JButton button;

   public CustomComponent() {
      textField = new JTextField();
      button = new JButton();

      button.setPreferredSize(new Dimension(25, 25));
      textField.setPreferredSize(new Dimension(125, 25));

      this.setLayout(new BorderLayout());

      this.add(textField, BorderLayout.CENTER);
      this.add(button, BorderLayout.EAST);
   }
}

class CustomComponentCellEditor extends DefaultCellEditor {

   private CustomComponent component;
   private JTextField textField;

   public CustomComponentCellEditor(CustomComponent component) {
      super(component.textField);
      this.component = component;
      textField = component.textField;
   }

   @Override
   public Component getComponent() {
      return component.textField;
   }

   @Override
   public boolean isCellEditable(final EventObject anEvent) {
      if (anEvent instanceof KeyEvent) {
         final KeyEvent keyEvent = (KeyEvent) anEvent;
         
         SwingUtilities.invokeLater(new Runnable() {

            public void run() {
               if (!Character.isIdentifierIgnorable(keyEvent.getKeyChar())) {
                  textField.setText(textField.getText() + keyEvent.getKeyChar());
               }
               textField.setCaretPosition(textField.getText().length());
               textField.requestFocusInWindow();
            }
         });
      }
      return super.isCellEditable(anEvent);
   }

   @Override
   public Component getTableCellEditorComponent(JTable table, Object value,
           boolean isSelected, int row, int column) {
      textField.setText(value.toString());
      return this.component;
   }
}

Now.

First, the ComponentListener was a bad idea, it didin't do what I thought it would.

SwingUtilities#invokeLater does not start a new Thread. Read the API.
Causes doRun.run() to be executed asynchronously on the AWT event dispatching thread.

Wrapping your custom code in invokeLater allows all pending Swing events (and there usually are some!) to be executed before your code. It's often seen that a requestFocus "doesn't work" -- because there are other events in the pipeline that steal the focus from your component of choce the instant after it gets it.

I haven't read the other solution offered, but you need to take care of ignorable characters, else if you press <Delete> (and maybe some other characters -- haven't tested exhaustively) to start editing, you'll get a non-printing character (displayed in most Windows fonts as a square box) in the text field.

db

It is useful for me too :)
thx!

Thanks a lot db. You pointed out quite a few things that I would've missed.

I am not sure whether to start a new forum or to wake this forum up. So apologies if I am wrong.

I used the code submitted by DarrylBurke to solve the same problem that I was having (the problem of this topic), particularly the "isCellEditable(final EventObject anEvent)" where the request focus code is. Everything seemed to work fine but now I noticed that pressing "F2" doesn't get the focus in the selected cell. I can post an SSCCE if required.

regards
nirvan.