试图在单击时来回更改 J 按钮的颜色

Question

I am still a newbie when it comes to Java and I am attempting to change the color of a button every time it is clicked by using action listeners. But I have tried many different ways and have come to a road block... I have tried using a Boolean but I am still having problems with figuring this out.

Color change = Color.BLACK    
B.setForeground(change);
B.setContentAreaFilled(false);
B.setFocusPainted(false);
B.setBounds(100, 175, 75, 75);

R.add(B); // R is the JFrame the button is added to...

             B.addActionListener(new ActionListener() { //Action Listener when pressing should change the color from Black to Red
                        public void actionPerformed(ActionEvent e) {
                            boolean right = false;
                            if (change == Color.BLACK) {
                                right = true;
                                B.setForeground(Color.red);
                            }
                        if (right == true) {
                            B.setForeground(Color.BLACK);
                            right = false;
                        }

                    }

                });

Answer 1

In this context...

B.addActionListener(new ActionListener() { //Action Listener when pressing should change the color from Black to Red
    public void actionPerformed(ActionEvent e) {
        boolean right = false;
        if (change == Color.BLACK) {
            right = true;
            B.setForeground(Color.red);
        }
        if (right == true) {
            B.setForeground(Color.BLACK);
            right = false;
        }
    }
});

right will always be false , as it's declared locally within the actionPerformed method.

Instead, make a instance field of the ActionListener , for example...

B.addActionListener(new ActionListener() { //Action Listener when pressing should change the color from Black to Red
    private boolean right = false;
    public void actionPerformed(ActionEvent e) {
        if (change == Color.BLACK) {
            right = true;
            B.setForeground(Color.red);
        }
        if (right == true) {
            B.setForeground(Color.BLACK);
            right = false;
        }

    }

});

Also, change never changes, so it's always BLACK , in which case I might be tempted to do something more like this...

B.addActionListener(new ActionListener() { //Action Listener when pressing should change the color from Black to Red
    private boolean right = false;
    public void actionPerformed(ActionEvent e) {
        if (!right) {
            B.setForeground(Color.red);
        } else if (right) {
            B.setForeground(Color.BLACK);
        }
        right = !right;
    }

});