更改JButton的背景颜色始终显示为灰色

Question

I am making a GUI interface and I am trying to change the background and foreground color of my windows with the following code:

  import java.awt.Color;
  import java.awt.Component;
  import java.awt.Container;

  import javax.swing.JButton;
  import javax.swing.JFrame;
  import javax.swing.JPanel;

  public class Test
  {

public static void changeColor(String typeOfColor, Component component, Color color)
{
    if (typeOfColor.equals("Background"))
    {
        component.setBackground(color);
    }
    else if (typeOfColor.equals("Foreground"))
    {
        component.setForeground(color);
    }

    if (component instanceof Container)
    {
        for (Component child : ((Container) component).getComponents())
        {
            changeColor(typeOfColor, child, color);
        }
    }
}

public static void main(String[] args)
{
    JPanel panel = new JPanel();
    JButton cancelButton = new JButton("Cancel");
    panel.add(cancelButton);

    changeColor("Background", panel, new Color(0, 255, 0));

    JFrame frame = new JFrame("Frame");

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setContentPane(panel);
    frame.setVisible(true);
    frame.pack();
}
}

However, no matter what is the color I choose, the buttons still display the background color as grey. How do I change the background color properly? I have looked around and most answers mention the setBackground method, but that does not work for me.

Thanks in advance!

Answer 1

Check on your current program the order of these lines:

panel.add(cancelButton);
changeColor("Background", panel, new Color(0, 255, 0));

If you have them in this order you get this output:

But if you change the order:

changeColor("Background", panel, new Color(0, 255, 0));
panel.add(cancelButton);

You get this:

Answer 2

Nicholas Smith solved my issue.

In the comments, he mentioned "It could be the background color for a JButton in your specific LookAndFeel can't be overridden."

I was setting the look and feel in my code and once I removed that part of the code, my buttons' background color was changed successfully.

Thanks to you!

Answer 3

You should change the LookAndFeel of your GUI with UIManager.setLookAndFeel() .

It happened to me several times in MacOSX