Java-如何在GridLayout中对齐JPanels

Question

This is currently what my form looks like:

I am trying to create a form with 4 columns of radio buttons but when I try to add the panels, holding the buttons, to the grid layout of another panel they seem to mis-align. I have not set any height of boundaries on the grid layout So I am not sure what is causing it to shift around.

My code:

public class Window extends JFrame{
public void paint(Graphics g) {
    super.paint(g); // ??
    getContentPane().setBackground(Color.WHITE); // background color
}

public static void main(String[] args) {
    Window w = new Window();
     w.setSize(1500,1000);
     w.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

     JLabel title = new JLabel("Menu", SwingConstants.CENTER);
     title.setFont(title.getFont().deriveFont(32f));

     Container titlePanel = new JPanel(); // used as a container
     titlePanel.setBackground(Color.WHITE);
     FlowLayout flow = new FlowLayout(); // Create a layout manager
     titlePanel.setLayout(flow);// assign flow layout to panel
     titlePanel.add(title); // add label to panel
     w.getContentPane().add(BorderLayout.NORTH,titlePanel);

     Container mains = new JPanel(new GridLayout(7, 0));
     mains.setBackground(Color.RED);
     JLabel mainsHeader = new JLabel("Mains");
     mainsHeader.setFont(mainsHeader.getFont().deriveFont(24f));
     mains.add(mainsHeader);

     Container noodles = new JPanel(new GridLayout(4, 0));
     noodles.setBackground(Color.GREEN);
     JLabel noodlesHeader = new JLabel("Noodles");
     noodlesHeader.setFont(noodlesHeader.getFont().deriveFont(24f));
     noodles.add(noodlesHeader);

     Container sauces = new JPanel(new GridLayout(3, 0));
     sauces.setBackground(Color.BLUE);
     JLabel saucesHeader = new JLabel("Sauce");
     saucesHeader.setFont(saucesHeader.getFont().deriveFont(24f));
     sauces.add(saucesHeader);


     Container extras = new JPanel(new GridLayout(6, 0));
     extras.setBackground(Color.YELLOW);
     JLabel extrasHeader = new JLabel("Extra");
     extrasHeader.setFont(extrasHeader.getFont().deriveFont(24f));
     extras.add(extrasHeader)

     Container menuSelection = new JPanel(new GridLayout(0,4));
     menuSelection.add(mains);
     menuSelection.add(noodles);
     menuSelection.add(sauces);
     menuSelection.add(extras);

     w.getContentPane().add(menuSelection);

     w.setVisible(true);
}   
}

Answer 1

You don't need to set a GridLayout on every sub-panel. You should only set it on mains , possibly with correct number of rows and columns.

If you only need labels, you can add them directly to mains, and it should lay them out for you.