Retaining Focus in Swing

[Ravi Kanth D]

Upon validating a JTextField value on the focusLost event, how do I retain the focus back on the same JTextField until correct value is entered? Thanks.
Ravi.

[Gregg Bolinger]

You should be able to call requestFocus() on the JTextField.

[Ravi Kanth D]

I tried but doesn' work. This is what I am doing...please let me know if I am wrong:
In focusLost event, I said if length() is < 4 then show an error message on the bottom text area...and requestFocus()
When I do not enter a value in first control and click on the second control...it does display the error message correctly...but cursor is still in the second control... I want it to come back to first control. How do I do it? Thanks.
Ravi.

[Gregg Bolinger]

You'll have to excuse the horrible looking GUI here, but this works for me.

import javax.swing.*;
import java.awt.GridLayout;
import java.awt.event.*;
public class App extends JFrame
{
   JTextArea text1;
   JTextArea text2;
   
public App()
{
this.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent w)
{
System.exit(0);
}
});

this.getContentPane().setLayout(new GridLayout(2,2));
text1 = new JTextArea();
text1.setText("Text 1");
this.getContentPane().add(text1);
JButton button1 = new JButton("Get Focus");
button1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
text1.requestFocus();
}
});
this.getContentPane().add(button1);
text2 = new JTextArea();
text2.setText("Text 2");
this.getContentPane().add(text2);
JButton button2 = new JButton("Get Focus");
button2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
text2.requestFocus();
}
});
this.getContentPane().add(button2);
this.pack();
this.setLocationRelativeTo(this);


}
public static void main(String[] args)
{
new App().setVisible(true);
}

}

[Ravi Kanth D]

Earlier I did something stupid...so it didn' work. Thx for your help again.
Ravi.

[Garandi Garandi]

Try inputListener

 
 myTextField.addinputListener(new InputListener(){
  public boolean verify(Component comp){
   //do verification in here
   // if verification passes return TRUE other return false
   // by returing false the focus will stay in textField
  }
});
 

I hope this will help
Thank you
Garandi

[VIJAY Yadlapati]

Try InputVerifier.
see InputVerifier. There is an example also..