我的JButton按下后仍停留在屏幕上

Question

My JButton's code is here:

JButton b = new JButton("JButton");
b.setBounds(100, 100, 100, 50);
b.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent arg0) {
        g.setColor(Color.BLACK);
        g.fillRect(0, 0, 1000, 500);
    }
});
frame.add(b);

This should make my screen go black after my button is pressed, but the button just stays on my JFrame. I can't find what is going wrong with this JButton, as I have in the past.
Another error I am encountering is that my JButton takes up the whole screen, even though I set its bounds to be a specific area.

Answer 1

You probably degine the Graphics g before the JButton b , thus the JButton is always displayed on the top layer.

You have to explicitely hide the button on the click action using the setVisible(false) method.

b.addActionListener(new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent arg0) {
        b.setVisible(false);
        g.setColor(Color.BLACK);
        g.fillRect(0, 0, 1000, 500);
    }
});