Question

我需要一个JFrame，里面有一个JPanel和一个JTable。我想在北方有jtable，在南方有JPanel。

当我在JFrame的南边添加它时，JPanel有两行，第二行不可见！如此令人困惑......请帮忙

package javaapplication18;

import javaapplication23.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.*;

import javax.swing.JTable.*;
import javax.swing.table.*;
import javax.swing.*;
import javax.swing.JFrame;

/**
 *
 * @author danial
 */
public class JavaApplication18 extends JFrame {

static JLabel jFN,jLN,jP,jR,jB,jIranianDate;
static JTextField tFN,tLN,tP,tR,tfBirthDate,tIranianDate;
static java.util.Date dateBirthDate;
static java.sql.Date  sqlBirthDate;




static  ResultSet rs;

static Object[][] info;
static Object[] columns={"ID","FirstName","LastName","P","R","BD"};

static DefaultTableModel dTable=new  DefaultTableModel(info,columns);

    public static void main(String[] args) {

       JavaApplication23 iranianDateInterface=new JavaApplication23() ;
       JavaApplication23 iranianDateInterface1=new JavaApplication23() ;

       iranianDateInterface1.setIranianDate(1364, 3, 14);

       String bg=iranianDateInterface1.getIranianDate();


     String iranianDate=iranianDateInterface.getIranianDate();
        System.out.println(bg);
     JFrame frame=new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Connection con;




        try {
            Class.forName("com.mysql.jdbc.Driver");
            con= DriverManager.getConnection("jdbc:mysql://localhost/kn","root","rit3000");
            Statement st=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
            String query = "Select * From tabmain";
            rs=st.executeQuery(query);

            while(rs.next()) {
                Object[] object=new Object[]{rs.getInt(1),rs.getString(2),rs.getString(3),rs.getInt(4),rs.getInt(5),rs.getDate(6)};
                dTable.addRow(object);

            }

        } catch (ClassNotFoundException ex) {

        }catch (SQLException e){
            System.out.println(e.getMessage());
        }
final JTable jTable=new JTable(dTable);
jTable.setRowHeight(jTable.getRowHeight()+10);
jTable.setFont( new Font("Serif",Font.PLAIN,20));
jTable.setAutoCreateRowSorter(true);
jTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);

JScrollPane scrollPane= new JScrollPane(jTable);



frame.add(scrollPane,BorderLayout.CENTER);

JButton add= new JButton("add");
add.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e){


    }
});
JButton remove=new JButton("remove");
remove.addActionListener(new ActionListener(){
    @Override
    public void actionPerformed(ActionEvent e){

    }
});


 jFN=new JLabel("First Name");
 jLN=new JLabel ("Last Name");
 jP=new JLabel("Payment");
 jR=new JLabel("Rest");
 jB=new JLabel("Birthday");
 jIranianDate=new JLabel("Cal");


 tFN=new JTextField(15);
 tLN=new JTextField (15);
 tP=new JTextField(7);
 tR=new JTextField(7);
 tIranianDate=new JTextField(iranianDate,8);


 tfBirthDate=new JTextField("0000-00-00",7);
JPanel inputPanel =new JPanel();


inputPanel.add(jFN);
inputPanel.add(tFN);
inputPanel.add(jLN);
inputPanel.add(tLN);
inputPanel.add(jP);
inputPanel.add(tP);
inputPanel.add(jR);
inputPanel.add(tR);
inputPanel.add(jB);
inputPanel.add(tfBirthDate);
inputPanel.add(add);
inputPanel.add(remove);
inputPanel.add(jIranianDate);
inputPanel.add(tIranianDate);

frame.add(inputPanel,BorderLayout.SOUTH);



frame.setSize(900,600);
frame.setVisible(true);


    }
}

Answer 1

当您使用BorderLayout时，您的目标是让几个控件具有一定的宽度（EAST / WEST）或高度（NORTH，SOUTH），并使其余的自动调整大小（CENTER）。要为边上的控件设置特定宽度或高度，请使用java.awt.Component类的首选size属性。

为什么JPanel的第二行不可见？

1 个答案: