Question

我有一个2D数组。 2D阵列已包含数据。我需要将它填入JTable并显示它。以下是我的编码，

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

class form extends JFrame implements ActionListener,WindowListener
{
    JButton b1; //processing takes place after button click
    JTable table;
    form()
    {
    setLayout(null);
    b1 = new JButton("Process");
    table = new JTable();
    table.setBounds(350,200,100,300);
    b1.setBounds(450,93,100,30);
    add(b1);
    b1.addActionListener(this);
    setSize(1000,1000);
    show();
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

public void actionPerformed(ActionEvent e)
{
    if(e.getSource()==b1)
    {
        data d = new data();
        String resultfile[][]=d.dis(); 
        for(int i=1;i<=resultfile.length;i++)
        {
            for(int j=1;j<=4;j++)
        {
            rows[i][j]=resultfile[i][j];
        }
    }

    Object[] title = {"A","B","C","D"};
    table = new JTable(rows, title);
    add(table);
  }
}

public void windowActivated(WindowEvent e1)
{ 
}

public void windowClosed(WindowEvent e2)
{ 
}

public void windowClosing(WindowEvent e3)
{
     dispose(); 
}

public void windowDeactivated(WindowEvent e4)
{
}

public void windowDeiconified(WindowEvent e5)
{ 
}

public void windowIconified(WindowEvent e6)
{ 
}

public void windowOpened(WindowEvent e7)
{ 
}

public static void main(String s[]) 
{
        form f = new form();
}    
}

处理发生但不显示表格。在上面的编码中，Arraypackage是我自己的包，它包含一个名为data的类，它包含一个名为dis的方法。 dis是一种返回2D String数组的方法。它已成功返回，resultfile包含正确的2D数组值。显示JTable时出现错误，即单击按钮后不显示表格。请在这件事上给予我帮助。

Answer 1

首先don't use null layout

问题是你是为jtable设置边界，但是你创建了一个新表并添加而没有给出边界。

form() {
    setLayout(null); // very bad
    b1 = new JButton("Process");
    table = new JTable(); //completely unnecessary 
    table.setBounds(350, 200, 100, 300); // set bounds for table

然后你只需添加全新的表而不指定边界。

 public void actionPerformed(ActionEvent e) {

            table = new JTable() ; assign new table
            add(table); // add //incorrect adding where is the bounds for new table ?

正确的方法/使用布局 [我使用了边框布局。你应该为你使用合适的一个]

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

class form extends JFrame implements ActionListener, WindowListener {

    JButton b1; //processing takes place after button click
    JTable table;

    form() {

        b1 = new JButton("Process");
        add(b1, BorderLayout.NORTH);
        b1.addActionListener(this);
        setSize(1000, 1000);
        setVisible(true);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == b1) {
            data d = new data();
            String resultfile[][] = d.dis();
            for (int i = 1; i <= resultfile.length; i++) {
                for (int j = 1; j <= 4; j++) {
                    rows[i][j] = resultfile[i][j];
                }
            }

            Object[] title = {"A", "B", "C", "D"};
            table = new JTable(rows, title);
            add(table);
            this.revalidate();
            this.repaint();
        }
    }

    public void windowActivated(WindowEvent e1) {
    }

    public void windowClosed(WindowEvent e2) {
    }

    public void windowClosing(WindowEvent e3) {
        dispose();
    }

    public void windowDeactivated(WindowEvent e4) {
    }

    public void windowDeiconified(WindowEvent e5) {
    }

    public void windowIconified(WindowEvent e6) {
    }

    public void windowOpened(WindowEvent e7) {
    }

    public static void main(String s[]) {
        form f = new form();
    }
}

JTable无法用Java显示

1 个答案: