formatting JTextfields using another class

Question

this is the code of the Gui Design class and below is the Class that provides functionality to the program. Im trying to get user input from the textfields so i can remove the text using the clearAll method and also save user input using the saveit method.I tried using nameEntry.setText(""); in the clearAll method but it wont work can someone help me please!

//Import Statements
import javax.swing.*;
import java.awt.*;
import javax.swing.JOptionPane;
import java.awt.event.*;


//Class Name
public class Customer extends JFrame {
    Function fun = new Function();

    public static void main(String[]args){
        Customer.setLookAndFeel();
        Customer cust = new Customer();
    }


    public Customer(){
        super("Resident Details");
        setSize(500,500);
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        FlowLayout two = new FlowLayout(FlowLayout.LEFT);
        setLayout(two);


        JPanel row1 = new JPanel();
        JLabel name = new JLabel("First Name",JLabel.LEFT);
        JTextField nameEntry = new JTextField("",20);
        row1.add(name);
        row1.add(nameEntry);
        add(row1);

        JPanel row2 = new JPanel();
        JLabel surname = new JLabel("Surname    ",JLabel.LEFT);
        JTextField surnameEntry = new JTextField("",20);
        row2.add(surname);
        row2.add(surnameEntry);
        add(row2);

        JPanel row3 = new JPanel();
        JLabel contact1 = new JLabel("Contact Details : Email                 ",JLabel.LEFT);
        JTextField contact1Entry = new JTextField("",10);
        FlowLayout newflow = new FlowLayout(FlowLayout.LEFT,10,30);
        setLayout(newflow);
        row3.add(contact1);
        row3.add(contact1Entry);
        add(row3);

        JPanel row4 = new JPanel();
        JLabel contact2 = new JLabel("Contact Details : Phone Number",JLabel.LEFT);
        JTextField contact2Entry = new JTextField("",10);
        row4.add(contact2);
        row4.add(contact2Entry);
        add(row4);

        JPanel row5 = new JPanel();
        JLabel time = new JLabel("Duration Of Stay                             ",JLabel.LEFT);
        JTextField timeEntry = new JTextField("",10);
        row5.add(time);
        row5.add(timeEntry);
        add(row5);


        JPanel row6 = new JPanel();
        JComboBox<String> type = new JComboBox<String>();
        type.addItem("Type Of Room");
        type.addItem("Single Room");
        type.addItem("Double Room");
        type.addItem("VIP Room");
        row6.add(type);
        add(row6);

        JPanel row7 = new JPanel();
        FlowLayout amt = new FlowLayout(FlowLayout.LEFT,100,10);
        setLayout(amt);
        JLabel amount = new JLabel("Amount Per Day                               ");
        JTextField AmountField = new JTextField("\u20ac ",10);
        row7.add(amount);
        row7.add(AmountField);
        add(row7);

        JPanel row8 = new JPanel();
        FlowLayout prc = new FlowLayout(FlowLayout.LEFT,100,10);
        setLayout(prc);
        JLabel price = new JLabel("Total Price                                         ");
        JTextField priceField = new JTextField("\u20ac ",10);
        row8.add(price);
        row8.add(priceField);
        add(row8);

        JPanel row9 = new JPanel();
        JButton clear = new JButton("Clear");
        row9.add(clear);
        add(row9);

        JPanel row10 = new JPanel();
        JButton save = new JButton("Save");
        save.addActionListener(fun);
        row10.add(save);
        add(row10);

        //Adding ActionListners
        nameEntry.addActionListener(fun);
        clear.addActionListener(fun);
        save.addActionListener(fun);

        setVisible(true);
    }

    private static void setLookAndFeel() {
            try {
                UIManager.setLookAndFeel(
                    "com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel"
                );
            } catch (Exception exc) {
            // ignore error
                }
    }

}

//Import Statements
import javax.swing.*;
import java.awt.*;
import java.awt.Color;
import javax.swing.JOptionPane;
import java.awt.event.*;


//Class Name
public class Function implements ActionListener {

    public void actionPerformed(ActionEvent e) {
        String command = e.getActionCommand();
        if(command.equals("Add Customer")) {
            Login();
        }
        else if(command.equals("Register")){
            Registration();
        }
        else if(command.equals("Exit")){
            System.exit(0);
        }       
        else if(command.equals("Clear")){
            ClearAllFields();
        }
        else if(command.equals("Save")){
            SaveIt();
        }
    }

    public static void Login(){
        Customer cust = new Customer();
    }

    public static void Registration(){
        //Do Nothing

    }
    //This clears all the text from the JTextFields
    public static void ClearAllFields(){

    }

    //This will save Info on to another Class
    public static void SaveIt(){


    }


}

Answer 1

Alternatively, you can make nameEntry known to the Function class by defining it before calling the constructor for Function and then passing it into the constructor, like:

JTextField nameEntry = new JTextField("",20);

Function fun = new Function(nameEntry);

Then, in Function, add nameEntry as a member variable of Function and make a constructor for Function which accepts nameEntry, (right after the "public class Function..." line), like:

JTextField nameEntry;

public Function(JTextField nameEntry) {
    this.nameEntry = nameEntry;
}

Now, the following will compile:

public void ClearAllFields(){
    nameEntry.setText("");
}

And, the Clear button will clear the name field.