Nothing in JFrame

[kkid]

I have just made a JFrame using this code but only the JFrame appears, not the text fields or the button. Why?

import java.awt.GridLayout;
import javax.swing.*;


public class LoginScreen extends JFrame {
   
    
    public LoginScreen(){
    
        setLayout(new GridLayout(3, 1));
        setVisible(true);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setSize(400, 250);
        
        JTextField usernameField = new JTextField("Username");
        JPasswordField passwordField = new JPasswordField("Password");
        JButton enterButton = new JButton("Submit");
        
    
        add(usernameField);
        add(passwordField);
        add(enterButton);
        
}
    
    
}

I initialise it using

LoginScreen loginScreen = new LoginScreen();

[DarrylBurke]

Set it visible only after all content has been added. Oh, and all Swing constructors and methods should be invoked on the EDT. Go through this tutorial for a better understanding: Lesson: Concurrency in Swing (The Java™ Tutorials > Creating a GUI With JFC/Swing)

db

[kkid]

Set visible only after it had all been added and it worked, thanks!