Java 8-Queens拼图按钮图标问题

Question

The problem I am running into is this: I have a grid of buttons in a JPanel, these buttons are supposed to change to an image of a queen when I click them. The code looks like this:

private Component createButtonBlack() {
    final JButton button = new BoardButton();
    final ImageIcon queen = new ImageIcon("/images/queen.png");

    button.setBackground(Color.BLACK);
    button.setPreferredSize(new Dimension(40, 40));

    class QueenClick implements ActionListener {

        public void actionPerformed(ActionEvent event) {
            button.setIcon(queen); 
            button.repaint();
        }
    } // end QueenClick

    ActionListener queenClicker = new QueenClick();
    button.addActionListener(queenClicker);
    return button;
} // end createButtonBlack

The problem (image not appearing) occurs on both the methods for creating black and white buttons but the methods are the same except for the color. Ideally I would like to be able to un-click the buttons and the image disappears but I do not know how to do that.

I am having difficulty with other parts of my 8queens GUI based problem so if you have any suggestions let me know!

Also if you need more code I will certainly supply it. Thank you.

Answer 1

State the exact problem when asking a question.

These buttons are supposed to change to an image of a queen when I click them.

So I'm guessing the icon doesn't change?

Did you:

1. Verify the ActionListener code is executed?
2. Verify the Icon was read properly?

You can easily add a System.out.println(...) to verify both of the above.

final ImageIcon queen = new ImageIcon("/images/queen.png");

I'm guessing the problem is the leading "/" in the path. The "/" tells the file system to look at the root of the drive.

if you have any suggestions let me know!

There is no need to create two methods. You can just do:

Component button = createButton();
button.setBackground( Color.BLACK );

There is no need to create individual ActionListeners. You can create a single generic listener with code like:

ActionListener queenClicker = new ActionListener()
{
    @Override
    public void actionPerformed(Action Event e)
    {
        JButton button = (JButton)e.getSource();
        button.setIcon( queen );
        //button.repaint(); // not needed the setIcon method will do the repaint()
    }
}