How do i make the output come in different columns?

问题

Im making a program that outputs, the numbers 1-10 in one column, the square of this in another and in the third the number in cube.

How can i make the program a little nicer so the columns really differ. And for every column i like to add a Title(Number, number squared, number cube).

//Sorry for my bad English

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

public class Del2upp3 extends JFrame implements ActionListener 
{
    int i;
    JLabel label2 = new JLabel();
    JPanel panel = new JPanel();
    JButton button = new JButton("Press");
    Del2upp3()
    {
        super ("Panel"); setSize (200,300);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Container con = this.getContentPane();
        con.add(panel);
        button.addActionListener(this);
        panel.add(label2);
        panel.add(button);
        setVisible(true);

    } 
    public void actionPerformed(ActionEvent event)
    {        
            Object source = event.getSource();
            if (source == button)  
        {

            StringBuilder string = new StringBuilder();
                for( i = 1; i< 11; i++){

                string.append("\n     ").append(i);
                string.append(", ").append(i*i);
                string.append(", ").append(i*i*i);

        }
               JOptionPane.showMessageDialog(null, string,"Data",
               JOptionPane.PLAIN_MESSAGE);
               setSize (200,200);
               setVisible(true); 
                 i = 0;
         }}
        public static void main(String[] args){new Del2upp3();} 
   }

回答1:

Formatting a String using HTML is an excellent and often overlooked idea (+1 to Maroun)

Something else that often gets over looked is the ability for JOptionPane to use JComponents

import java.awt.EventQueue;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;

public class TableOptionPane {

    public static void main(String[] args) {
        new TableOptionPane();
    }

    public TableOptionPane() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                Integer[][] values = new Integer[10][3];
                StringBuilder string = new StringBuilder();
                for (int i = 1; i < 11; i++) {
                    values[i - 1][0] = i;
                    values[i - 1][1] = i * i;
                    values[i - 1][2] = i * i * i;
                }
                DefaultTableModel model = new DefaultTableModel(values, new Object[]{"i", "i * i", "i * i * i"});
                JTable table = new JTable(model);
                JOptionPane.showMessageDialog(null, new JScrollPane(table), "Data", JOptionPane.PLAIN_MESSAGE);
            }
        });
    }
}

The has the added benifit of providing a bases from which you could support such operations as "copy" or even edibility of the data, if such things were of use to you...

You may find more details at How to use Dialogs

回答2:

It's better to use JTable in your case.

But you can use HTML Tags and do something like this:

builder.append("<html><table border=1><tr><td>column1</td><td>column2</td><td></tr>");
string.append("<tr><td>");
string.append(.....);
string.append("</td><td>");
...
string.append("</td></tr>");
string.append("</table></html>");

~~Or:~~

textArea.setText("column1\t\tcolumn2\n");  
textArea.append("column1\t\tcolumn2\n");  
textArea.append(...);

But it's not recommended since your text can go out of the column.

来源：https://stackoverflow.com/questions/16450293/how-do-i-make-the-output-come-in-different-columns

标签

java

swing

for-loop

multiple-columns