How to remove border corners in JButton?

Question

I have a JButton with FlatLaf GUI.

FlatLaf allow me set client properties to some components, in this case I use 'JButton.buttonType' property

Example:

JButton myButton = new JButton();
myButton.putClientProperty("JButton.buttonType","roundRect");

And this paints a rounded button.

The problem occurs when I send an Icon to the button

myButton.setIcon(new ImageIcon(getClass().getResource("/path/image.png")));

And this paints the image like:

As can be seen, this paints the image using the rectangle of my button. The borderPaint can be seen, and effectively is a perfect circle, but the border corners always show.

How can I remove those corners?

So you just want to show the portion of the image in the circle. — matt, Aug 14 '21 at 19:24
How about this answer? https://stackoverflow.com/a/31424601/2067492 where you modify the image that you use with the button. — matt, Aug 14 '21 at 19:26
Your problem is, the button isn't clipping the bounds of the "rounded" edge - this is an issue with the look and feel itself and you'll need to take it up with the authors. As has been already been suggested, you could "fake it" but generating a circular image to start with — MadProgrammer, Aug 14 '21 at 22:54
Exactly, I just want show the portion of the image in the circle. — Angel Ponce, Aug 15 '21 at 00:47
@matt Thanks to reference to https://stackoverflow.com/a/31424601/2067492, this answer help me — Angel Ponce, Aug 15 '21 at 01:02
Does this answer your question? [How to make Circle image Label in Java?](https://stackoverflow.com/questions/31423130/how-to-make-circle-image-label-in-java) — matt, Aug 15 '21 at 06:30
@AngelPonce, does the custom Icon approach not work? I can't test it since I don't use the Flat LAF. — camickr, Aug 15 '21 at 15:49

camickr · Answer 1 · 2021-08-15T20:31:37.710

You could create a custom Icon class:

import java.awt.*;
import java.awt.geom.*;
import java.awt.image.*;
import java.net.*;
import javax.swing.*;

public class OvalImageIcon extends ImageIcon
{
    private BufferedImage oval;

    public OvalImageIcon()
    {
        super();
    }

    public OvalImageIcon(String fileName)
    {
        super(fileName);
    }

    public OvalImageIcon(URL url)
    {
        super(url);
    }

    @Override
    public void setImage(Image image)
    {
        super.setImage(image);

        oval = null;
    }

    @Override
    public void paintIcon(Component c, Graphics g, int x, int y)
    {
        if (oval == null)
        {
            oval = new BufferedImage(getIconWidth(), getIconHeight(), BufferedImage.TYPE_INT_ARGB);
            Graphics2D ovalGraphics = oval.createGraphics();
            ovalGraphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
            ovalGraphics.drawImage(getImage(), 0, 0, null);

            //  Use AlphaComposite to apply oval mask

            Shape ovalMask = new Ellipse2D.Double(0, 0, getIconWidth(), getIconHeight());
            Area imageArea = new Area( new Rectangle(0, 0, getIconWidth(), getIconHeight()) );
            imageArea.subtract( new Area( ovalMask ) );
            ovalGraphics.setComposite(AlphaComposite.getInstance(AlphaComposite.DST_IN));
            ovalGraphics.setColor( new Color(0, 0, 0, 0) );
            ovalGraphics.fill(imageArea);
            ovalGraphics.dispose();
        }

        g.drawImage(oval, x, y, null);
    }

    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }

    public static void createAndShowGUI()
    {
        Icon icon = new OvalImageIcon("mong.jpg");
        JLabel label = new JLabel( icon );

        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(label);
        f.pack();
        f.setLocationRelativeTo( null );
        f.setVisible(true);
    }
}

Above code should paint an oval of the image based on the width and height of the original image.

How to remove border corners in JButton?

1 Answers1