Update JTextField in another class

[JoeMac3313]

The question is how can I update the JTextField in Class CreditDisplayFi eld when I hit the button in class CreditButton? I wrote in a test printing to console to make sure the "logic.addCredi ts();" in the class ButtonHandler is being done and that works but the "creditDisplay. update();" in the same area still shows 0 and does not update w/ the added amount of credits. This was originally a homework assignment that I completed in 3 very large classes and I was told to break it down to better understand OOP so I am trying to get it to work. Any suggestions on how to write it would be very helpful.

JoeMac

import java.awt.FlowLayout;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;


public class CreditDisplayField extends JPanel{
	
	private JPanel creditDisplay;
	private JLabel credits;
	private JTextField creditsLeft;
	private SlotLogic logic = new SlotLogic();
	
	CreditDisplayField(){
		creditDisplay = new JPanel();
		credits = new JLabel("Credits");
		creditsLeft = new JTextField(6);
		creditsLeft.setText("" + logic.getCredits());
		creditDisplay.add(credits);
		creditDisplay.add(creditsLeft);
		this.setLayout(new FlowLayout());
		this.add(creditDisplay);
	}
	public void update(){

		creditsLeft.setText("" + logic.getCredits());

	}

}

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;



public class CreditButton extends JPanel {
	private JPanel creditButton;
	private JButton credit;
	private ButtonHandler addCredits = new ButtonHandler();
	SlotLogic logic = new SlotLogic();
	CreditDisplayField creditDisplay = new CreditDisplayField();
	
	CreditButton(){
		creditButton = new JPanel();
		credit = new JButton("Add Credits");
		creditButton.add(credit);
		
		credit.addActionListener(addCredits);
		
		this.setLayout(new FlowLayout());
		this.add(creditButton);
	}
	
	
	private class ButtonHandler implements ActionListener{	
		public void actionPerformed(ActionEvent event){
			logic.addCredits();
			creditDisplay.update();
		}
	}// inner class ButtonHandler
}