The problem is that your initial image does not match the dimensions of the selected image so, the selected image will appear in a different location, bottom right in this case.
You could create a placeholder for your initial 'unselected' image:
public class PlaceHolderIcon implements Icon {
private final int width;
private final int height;
public PlaceHolderIcon(int width, int height) {
this.width = width;
this.height = height;
}
public int getIconHeight() {
return height;
}
public int getIconWidth() {
return width;
}
public void paintIcon(Component c, Graphics g, int x, int y) {
}
}
and replace your first zero-dimension image with:
ImageIcon selectedIcon = new ImageIcon("Image.png");
Image image = selectedIcon.getImage();
PlaceHolderIcon placeHolderIcon = new PlaceHolderIcon(image.getWidth(this), image.getHeight(this));
JToggleButton layoutButton = new JToggleButton();
layoutButton.setIcon(placeHolderIcon);
layoutButton.setFocusPainted(false);
layoutButton.setSelectedIcon(selectedIcon);