how to print text from a JtextField by clicking a JButton

Question

I'm creating a little program for my self to learn Java now I did make a GUI with 12 JTextFields and now I want to use the text that's in the text fields in another class where I print them out.

When I press the button class print is successful, summand I get the last System.out.println("Test if class is triggerd") in my console but I don't get the JTextFields output in the console

Class Frame1

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JTextField;
import java.awt.Color;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;

public class Frame1 {

    public JFrame frmCratingRecipieGenerator;
    public JTextField txtSlot;
    public JTextField textField_1;
    public JTextField textField_2;
    public JTextField textField_3;
    public JTextField textField_4;
    public JTextField textField_5;
    public JTextField textField_6;
    public JTextField textField_7;
    public JTextField textField_8;
    public JTextField textField_9;
    public JTextField textField_10;
    public JTextField textField_11;
    public JLabel lblNewLabel;
    public String slot1;
    public String slot2;
    public String slot3;
    public String slot4;
    public String slot5;
    public String slot6;
    public String slot7;
    public String slot8;
    public String slot9;
    public String output;
    public String output_count;
    public String file_num;


    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Frame1 window = new Frame1();
                    window.frmCratingRecipieGenerator.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the application.
     */
    public Frame1() {
        initialize();
    }

    /**
     * Initialize the contents of the frame.
     */
    public void initialize() {
        frmCratingRecipieGenerator = new JFrame();
        frmCratingRecipieGenerator.setResizable(false);
        frmCratingRecipieGenerator.setTitle("Crating Recipie Generator Alpha 1");
        frmCratingRecipieGenerator.getContentPane().setBackground(new Color(192, 192, 192));
        frmCratingRecipieGenerator.setBounds(100, 100, 452, 248);
        frmCratingRecipieGenerator.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frmCratingRecipieGenerator.getContentPane().setLayout(null);

        txtSlot = new JTextField();
        txtSlot.setBounds(10, 19, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(txtSlot);
        txtSlot.setColumns(10);

        textField_1 = new JTextField();
        textField_1.setBounds(106, 19, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_1);
        textField_1.setColumns(10);

        textField_2 = new JTextField();
        textField_2.setBounds(202, 19, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_2);
        textField_2.setColumns(10);

        textField_3 = new JTextField();
        textField_3.setBounds(10, 50, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_3);
        textField_3.setColumns(10);

        textField_4 = new JTextField();
        textField_4.setBounds(106, 50, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_4);
        textField_4.setColumns(10);

        textField_5 = new JTextField();
        textField_5.setBounds(202, 50, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_5);
        textField_5.setColumns(10);

        textField_6 = new JTextField();
        textField_6.setBounds(10, 81, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_6);
        textField_6.setColumns(10);

        textField_7 = new JTextField();
        textField_7.setBounds(106, 81, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_7);
        textField_7.setColumns(10);

        textField_8 = new JTextField();
        textField_8.setBounds(202, 81, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_8);
        textField_8.setColumns(10);

        textField_9 = new JTextField();
        textField_9.setBounds(351, 19, 86, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_9);
        textField_9.setColumns(10);

        textField_10 = new JTextField();
        textField_10.setBounds(351, 81, 46, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_10);
        textField_10.setColumns(10);

        textField_11 = new JTextField();
        textField_11.setText("1");
        textField_11.setBounds(351, 50, 46, 20);
        frmCratingRecipieGenerator.getContentPane().add(textField_11);
        textField_11.setColumns(10);

        JLabel lblFileId = new JLabel("File ID");
        lblFileId.setFont(new Font("Tahoma", Font.PLAIN, 16));
        lblFileId.setHorizontalAlignment(SwingConstants.LEFT);
        lblFileId.setBounds(298, 82, 86, 14);
        frmCratingRecipieGenerator.getContentPane().add(lblFileId);

        JLabel lblOutput = new JLabel("Output");
        lblOutput.setFont(new Font("Tahoma", Font.PLAIN, 16));
        lblOutput.setBounds(298, 20, 58, 14);
        frmCratingRecipieGenerator.getContentPane().add(lblOutput);

        JLabel lblCount = new JLabel("Count");
        lblCount.setFont(new Font("Tahoma", Font.PLAIN, 16));
        lblCount.setBounds(298, 51, 52, 14);
        frmCratingRecipieGenerator.getContentPane().add(lblCount);


        JLabel lblThisJavaProgram = new JLabel("This Java program is coded by Jason");
        lblThisJavaProgram.setFont(new Font("Tahoma", Font.PLAIN, 16));
        lblThisJavaProgram.setBounds(10, 179, 270, 20);
        frmCratingRecipieGenerator.getContentPane().add(lblThisJavaProgram);

        JLabel TestLabel = new JLabel("");
        TestLabel.setFont(new Font("Tahoma", Font.PLAIN, 16));
        TestLabel.setBounds(391, 179, 46, 19);
        frmCratingRecipieGenerator.getContentPane().add(TestLabel);

        JButton btnNewButton = new JButton("Generate the McFunction File's");
        btnNewButton.setBounds(10, 108, 427, 60);
        btnNewButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                TestLabel.setText(textField_10.getText());              
                print name = new print();
                name.Print();
            }
        });
        frmCratingRecipieGenerator.getContentPane().add(btnNewButton);

        lblNewLabel = new JLabel("Last File num");
        lblNewLabel.setFont(new Font("Tahoma", Font.PLAIN, 16));
        lblNewLabel.setBounds(287, 182, 110, 14);
        frmCratingRecipieGenerator.getContentPane().add(lblNewLabel);


        this.slot1 = txtSlot.getText();
        this.slot2 = textField_1.getText();
        this.slot3 = textField_2.getText();;
        this.slot4 = textField_3.getText();;
        this.slot5 = textField_4.getText();;
        this.slot6 = textField_5.getText();;
        this.slot7 = textField_6.getText();;
        this.slot8 = textField_7.getText();;
        this.slot9 = textField_8.getText();;
        this.output = textField_9.getText();
        this.output_count = textField_11.getText();
        this.file_num = textField_10.getText();



        }


}

Class print

package example;

public class print {
    public void Print() {
        Frame1 slots =  new Frame1();
        String slot1 = slots.slot1;
        String slot2 = slots.slot2;
        String slot3 = slots.slot3;
        String slot4 = slots.slot4;
        String slot5 = slots.slot5;
        String slot6 = slots.slot6;
        String slot7 = slots.slot7;
        String slot8 = slots.slot8;
        String slot9 = slots.slot9;
        String output = slots.output;
        String output_count = slots.output_count;
        String file_num = slots.file_num;

        System.out.println(slot1);
        System.out.println(slot2);
        System.out.println(slot3);
        System.out.println(slot4);
        System.out.println(slot5);
        System.out.println(slot6);
        System.out.println(slot7);
        System.out.println(slot8);
        System.out.println(slot9);
        System.out.println(output);
        System.out.println(output_count);
        System.out.println(file_num);
        System.out.println("Test if class is triggerd");
    }


}

Answer 1

This is happening because you create on the print class a new Object of frame1 so the variables by default are null. You can add on the Print method a list parameter that stores all the Strings in that list.

public void Print(List<String> slots) {
    System.out.println(slots.get(0));
    System.out.println(slots.get(1));
    System.out.println(slots.get(2));
    System.out.println(slots.get(3));
    System.out.println(slots.get(4));
    System.out.println(slots.get(5));
    System.out.println(slots.get(6));
    System.out.println(slots.get(7));
    System.out.println(slots.get(8));
    System.out.println(slots.get(9));
    System.out.println(slots.get(10));
    System.out.println(slots.get(11));
}

and redefine before the method call all the variables and store them in the list.

You can learn some things about Java's lists here

If you are struggling finding the code I made it for you

            slot1 = txtSlot.getText();
            slot2 = textField_1.getText();
            slot3 = textField_2.getText();;
            slot4 = textField_3.getText();;
            slot5 = textField_4.getText();;
            slot6 = textField_5.getText();;
            slot7 = textField_6.getText();;
            slot8 = textField_7.getText();;
            slot9 = textField_8.getText();;
            output = textField_9.getText();
            List<String> slots = new ArrayList<String>();
            slots.add(slot1);
            slots.add(slot2);
            slots.add(slot3);
            slots.add(slot4);
            slots.add(slot5);
            slots.add(slot6);
            slots.add(slot7);
            slots.add(slot8);
            slots.add(slot9);
            slots.add(output);
            slots.add(output_count);
            slots.add(file_num);
            output_count = textField_11.getText();
            file_num = textField_10.getText();
            TestLabel.setText(textField_10.getText());     

            print name = new print();

            name.Print(slots);

and Print class:

public void Print(List<String> slots) {


    System.out.println(slots.get(0));
    System.out.println(slots.get(1));
    System.out.println(slots.get(2));
    System.out.println(slots.get(3));
    System.out.println(slots.get(4));
    System.out.println(slots.get(5));
    System.out.println(slots.get(6));
    System.out.println(slots.get(7));
    System.out.println(slots.get(8));
    System.out.println(slots.get(9));
    System.out.println(slots.get(10));
    System.out.println(slots.get(11));
    System.out.println("Test if class is triggerd");
}