Question about making a JAVA GUI of a certain format

I am trying to make a GUI th开发者_开发问答at looks something like this:

I only know how to use the BorderLayout which has space for 5 buttons. North, West, Center, East, and South.

Since I need to have 6 components on the top line, this approach can't work. I'm not sure how to make it so that I can have more than 1 component on the top line. Are there other layouts that I can use or is there some way I can manipulate BorderLayout so that I can put 6 components on the top line?

What you need to do is nest components inside of other components. For example, the top (North) should be one JPanel. That JPanel will contain the 6 components on the top.

The code may look similar to the following:

JPanel northPane = new JPanel();
northPane.add(new JLabel("Principle: "));
northPane.add(principleTextBox);
... and so on
mainPanel.setLayout(new BorderLayout());
mainPanel.add(northPanel, BorderLayout.NORTH);

The Center component will probably be another JPanel containing the two center buttons. And the South component will be another JPanel containing the single JLabel or simply the JLabel.

If you don't have to use a BorderLayout for the main panel, it may be easier to use a BoxLayout.

Once again I turn to miglayout, the absolute best layout manager for Java. No nested JPanels, just a simple layout using string based constraints.

With debug mode on:

After resizing the window (note the ratio of the size of the textfields remains the same)

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import net.miginfocom.swing.MigLayout;

/**
 *
 * @author nicholasdunn
 */
public class InterestCalculator extends JPanel {

    public InterestCalculator() {
        super(new MigLayout("debug, fill", "align center"));
        // Make 6 components cram into one cell
        add(new JLabel("Principal:"), "split 6");
        // This textfield grows at twice the normal rate
        add(new JTextField(), "growx 200");
        add(new JLabel("Interest rate (percentage):"));
        // This one at a normal rate
        add(new JTextField(), "growx 100");
        add(new JLabel("Years:"));
        // This one at half the normal rate
        add(new JTextField(), "growx 50, wrap");

        // The row with the two buttons
        add(new JButton("Compute simple interest"), "split 2");
        add(new JButton("Compute compound interest"), "wrap");

        // The result label
        add(new JLabel("The result with simple interest would be"));
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new InterestCalculator();
        frame.add(panel);
        frame.pack();
        frame.setVisible(true);
    }
}

If I were recreating that UI, I would start with a JPanel using a GridLayout with 3 rows and 1 column. In each column I would add a child JPanel.

Then for each row I would use a GridBagLayout to position the components.

Here is a tutorial about layout managers.

Remember that you can always add several elements to a JPanel and apply a specific layout to that JPanel. Then you can nest panels(add panels inside other panels).