How to turn on buttons once turned off in ActionListener

Question

Problem: Code does not turn the button back on (Example gives it 5 seconds for you to press)

Example code:

public static void main(String[] args) throws InterruptedException
{
    Example call = new Example();
    Thread.sleep(5000);
    call.ButtonSwitch(1);
}

NOTE: this is the smallest coding i could make to show my problem

public class Example extends JFrame implements ActionListener {

static Example frame2 = new Example();

GridLayout experimentLayout = new GridLayout(0,1);

JPanel Game = new JPanel();

JButton button1 = new JButton("Press");

public Example()
{
    Create();
}

public void Set() 
{
    setResizable(false);
}

public static void Create() {
    /* Use an appropriate Look and Feel */
    try {
        UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
    } catch (UnsupportedLookAndFeelException ex) {
        ex.printStackTrace();
    } catch (IllegalAccessException ex) {
        ex.printStackTrace();
    } catch (InstantiationException ex) {
        ex.printStackTrace();
    } catch (ClassNotFoundException ex) {
        ex.printStackTrace();
    }
    /* Turn off metal's use of bold fonts */
    UIManager.put("swing.boldMetal", Boolean.FALSE);

    //Schedule a job for the event dispatch thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}
    public static void createAndShowGUI() 
    {
        //Create and set up the window.
        frame2.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        //Set up the content pane.
        frame2.addComponentsToPane(frame2.getContentPane());
        //Display the window.
        frame2.pack();
        frame2.setVisible(true);
    }

    public void addComponentsToPane(final Container pane) 
    {
        Game.setLayout(experimentLayout);
        JPanel controls = new JPanel();
        controls.setLayout(new GridLayout(2,3));

        //Set up components preferred size
        JButton b = new JButton("Just fake button");
        Dimension buttonSize = b.getPreferredSize();
        Game.setPreferredSize(new Dimension((int)(buttonSize.getWidth() * 2),
                (int)(buttonSize.getHeight() * 1)* 4));

        Game.add(button1);
        button1.addActionListener(this);

        //Process the Apply gaps button press
        pane.add(Game, BorderLayout.NORTH);
        pane.add(new JSeparator(), BorderLayout.CENTER);
        pane.add(controls, BorderLayout.SOUTH);

    }
    //Turns button off On Click
    public void actionPerformed(ActionEvent e) 
    {
        if (e.getSource() == button1)
        {
            button1.setEnabled(false);
        }
    }

    //This does not turn the button on but tries to
    public void ButtonSwitch(int num)
    {
        if (num == 1)
        {
            System.out.println("This is called");
            button1.setEnabled(true);
        }
    }

}

I want to make the method Enable the button, but if this is not possible a way to do this in action listener without user input would be the second option (which would look like the Button switch method placed inside the ActionListener)

Answer 1

The problem comes from the bad design of the class. The point is that you are not calling setEnabled(true) and setEnabled(false) on the same button1 . In your main ,

Example call = new Example();
Thread.sleep(5000);
call.ButtonSwitch(1);

the last line invokes setEnabled(true) on the button of call , while the actionPerformed invokes the setEnabled(false) on the button of frame2 .

Regardless, you are doing it wrong:

1. Don't mix the main (entry) thread with the EDT.
2. Don't hold a member of the same class type as the containing class (unless there's a special reason to do so).

Here is a real MCVE of a working code:

public class Example extends JFrame {

    JButton button = new JButton("Press");
    Timer timer = new Timer(5000, e -> button.setEnabled(true));

    public Example() {

        add(button);
        button.addActionListener(e -> { 
            button.setEnabled(false);
            timer.start();
        });

        timer.setRepeats(false);

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
        setVisible(true);
    }

    public static void main(String[] args) throws InterruptedException {

        SwingUtilities.invokeLater(() -> new Example());
    }
}

Notes:

• Method and non-final variable names start with a lowercase.
• Don't use setPreferredSize , override getPreferredSize instead.