Focus Problem

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1

I am having a problem with a program that is supposed to change a JLabel’s text based on which of three jtextfields is selected. I get no errors when I compile but the label will not change. Here is my code:

import java.util.Vector;
import java.awt.;
import java.awt.event.;
import javax.swing.;
import java.io.;
import java.awt.BorderLayout;
import java.awt.FlowLayout; import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import java.awt.GridLayout;
import javax.swing.JTextField;
import java.util.*;

public class DataEntry extends JFrame implements FocusListener
{
private JLabel label1;
private JLabel label2;
private JLabel label3;
private JLabel label4;
private JPanel Panel1;
private JPanel Panel2;
private JPanel Panel3;
//public MaxLengthTextDocument maxLength;
private JTextField textField1;
private JTextField textField2;
private JTextField textField3;
private BorderLayout layout;
private GridLayout gridLayout1;
private FlowLayout flowLayout1;
//public static final int WHEN_FOCUSED;
private String a;
private String b;
private String c;
private int f;

private int x;
private int y;
private int z;



public DataEntry()
{
	super("Data Entry");

	layout = new BorderLayout(5,10);
	flowLayout1= new FlowLayout();
	setLayout(layout);
	Panel1 = new JPanel();
	Panel2=new JPanel();
	Panel3=new JPanel();
	Random randomNumber=new Random();
	x=1000 + randomNumber.nextInt(9000);
	y=1000 + randomNumber.nextInt(9000);
	z=1000 + randomNumber.nextInt(9000);
    //MaxLengthTextDocument maxLength = new MaxLengthTextDocument();
    //maxLength.setMaxChars(4);

	a=String.valueOf(x);
	b=String.valueOf(y);

	c=String.valueOf(z);

	label1=new JLabel(a);
	label2=new JLabel(b);
	label3=new JLabel(c);
	label4=new JLabel("");

	add(Panel1,BorderLayout.NORTH);
	Panel1.setLayout(flowLayout1);
	Panel1.add(label1);
	Panel1.add(label2);
	Panel1.add(label3);

	add(Panel2,BorderLayout.SOUTH);
	textField2=new JTextField(4);
	textField3=new JTextField(4);
	textField1=new JTextField(4);
	textField1.addFocusListener(this);
	textField3.addFocusListener(this);
	textField2.addFocusListener(this);

    textField1.setName("David");
    textField2.setName("John");
	//textField1.setActionCommand("First");
	//textField2.setActionCommand("Second");
	Panel2.add(textField1);
	Panel2.add(textField2);
	Panel2.add(textField3);

	add(Panel3,BorderLayout.CENTER);
	Panel3.setLayout(flowLayout1);
	Panel3.add(label4);




}
public void focusGained(FocusEvent e) {

if(getName()=="John")
{
	label4.setText("Hello");
}

}

public void focusLost(FocusEvent e) {

}

}

2

Change your focusGained method to the following:


public void focusGained(FocusEvent e) {
	System.out.println("focusGained");
	if(e.getComponent() instanceof JTextField) {
		JTextField jTextField = (JTextField) e.getComponent();
		if(jTextField.getName() != null && jTextField.getName().equals("John")) {
			label4.setText("Hello");
		} else {
			label4.setText("");
		}
	}
}

That should work a bit better for you.

Your current ‘getName()’ method is calling ‘getName()’ on your JFrame, not the component that is getting the focus event called on it…

3

Thanks for the help hooknc, its working fine now.