Trouble with ActionListener and an IF statement

Question

I am currently having two problems both at which i have been trying to solve for the past 3 hours.

1. I cant get the input--; to decrement if input is not == to 0

2. I cant get the JTextField input to update the the value i assign to it once the program is running. Ill type 22 in the running program click start and it will go to "test99". Pictures is an example of how i entered the value 66 then i pressed start and test99 came up instead of test66

I hope I was able to explain my problem to an extent you will be able to understand. I have read a lot of documentation about action listeners but currently the idea wont click for me. Any constructive criticism is welcome.

I also simplified my problem down as best as I could.

package test;

import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.BorderLayout;
import javax.swing.SwingConstants;
import javax.swing.Timer;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JTextField;
import javax.swing.JButton;

public class test {

private JFrame frame;
private JButton btnStart;

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

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

/**
 * Initialize the contents of the frame.
 */

private void initialize() {
    frame = new JFrame();
    JLabel Output = new JLabel("Time left: ");
    Output.setHorizontalAlignment(SwingConstants.CENTER);
    frame.getContentPane().add(Output, BorderLayout.CENTER);
    JTextField Input = new JTextField();
    btnStart = new JButton("start");

    Input.setText("99");
    int input = (int) (Double.parseDouble(Input.getText()));

    Input.setHorizontalAlignment(SwingConstants.CENTER);
    frame.getContentPane().add(Input, BorderLayout.SOUTH);
    Input.setColumns(10);
    frame.getContentPane().add(btnStart, BorderLayout.NORTH);
    frame.setBounds(100, 100, 300, 300);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    Input.addActionListener(new ActionListener() {
          public void actionPerformed(ActionEvent e) {

          }
        });


    Timer t = new Timer(1000, new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            Output.setText("test" + input);

            if (input == 0) {
                ((Timer) e.getSource()).stop();
            }
            input--;
        }

    });

    btnStart.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            t.start();
        }
    });

}

}

Answer 1

I recommand to declare your input variables not in your function, but in your class. Otherwise you run into scope problems. Example:

public class test {

  private JFrame frame;
  private JButton btnStart;
  private int input;
  private JTextField Input;

  //...

}

Should fix the issue :)

I am not enterily sure about the second issue but if you want to count down from the entered value, you have to update your action listener:

btnStart.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        input = (int) (Double.parseDouble(Input.getText()));
        t.start();
    }
});