GridLayout Help in Java

I have a JPanel with the following code:

JPanel pane = new JPanel();
pane.setLayout(new GridLayout(3, 2, 10, 30));
final JTextField fileName = new JTextField();
pane.add(fileName);
JButton creater = new JButton("Create File");
pane.add(creater);
JButton deleter = new JButton("Delete File");
pane.add(deleter);

I was wondering, how do I make it so that the JTextField开发者_如何学JAVA takes up two spaces on the GridLayout, while having the two buttons share a row by taking up one space each on the same line?

It is a hard to do with GridLyout. You have create wider cells (e.g. new GridLayout(2, 2, 10, 30), then add TextField to the fist cell. Then you have to create yet another panel with GridLayout(2, 1), put it into the cell in second line and add your button into 1 st cell of this nested grid layout.

Shortly you need GridLayout into other GridLayout.

There are better tools to implement this. First take a look on GridBagLayout. It is just to be sure that life is not always pick-nick :). Then take a look on alternative solutions like MigLayout. It is not a part of JDK but it really powerful tool that makes your life easier.

You cannot do column spans with GridLayout. I recomend you try GridBagLayout and GridBagConstraints

After trashing the suggestion of 3rd party layouts, and since I possess a malevolent hatred of GBL, I thought it was about to time to 'put my code where my mouth is' for public scrutiny (and trashing).

This SSCCE uses a nested layout.

import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;

class SimpleLayoutTest {

    public static void main(String[] args) {
        Runnable r = new Runnable() {
            public void run() {
                JPanel ui = new JPanel( new BorderLayout(20,20) );
                // I would go for an EmptyBorder here, but the filled
                // border is just to demonstrate where the border starts/ends
                ui.setBorder( new LineBorder(Color.RED,15) );

                // this should be a button that pops a JFileChooser, or perhaps
                // a JTree of the existing file system structure with a JButton
                // to prompt for the name of a new File.
                final JTextField fileName = new JTextField();
                ui.add(fileName, BorderLayout.NORTH);

                JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 10, 30));
                ui.add(buttonPanel, BorderLayout.CENTER);

                JButton creater = new JButton("Create File");
                buttonPanel.add(creater);
                JButton deleter = new JButton("Delete File");
                buttonPanel.add(deleter);

                JOptionPane.showMessageDialog(null, ui);
            }
        };
        SwingUtilities.invokeLater(r);
    }
}

Take a look at the tutorial on How to Use GridBagLayout.

Sample code:

    JPanel pane = new JPanel();
    GridBagLayout gridbag  = new GridBagLayout();
    pane.setLayout(gridbag);
    GridBagConstraints c = new GridBagConstraints();

    final JTextField fileName = new JTextField();
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridwidth = 2;
    c.gridx = 0;
    c.gridy = 0;
    pane.add(fileName, c);

    JButton creater = new JButton("Create File");
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridwidth = 1;
    c.gridx = 0;
    c.gridy = 1;
    pane.add(creater, c);

    JButton deleter = new JButton("Delete File");
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 1;
    pane.add(deleter, c);