How to manage sizes of a JPanel inside a JFrame

Question

I want to arrange 3Panels to my JFrame in a way that the first panel is in the top of the two side by side panels. I can't put the screenshot because i'm just new at this site.

Here is the code for my program. Just ask if i am lacking of something here.

package images;
import javax.swing.*;

import java.awt.Event.*;
import java.awt.*;

public class B1 extends JFrame{

public static final long serialVersionUID = 0L;

public static void main(String[] args){

    new Display();

}

}

class Display extends JFrame{

public static final long serialVersionUID = 0L;

private JButton Bnum1,Bnum2,Bnum3,Bnum4,Bnum5,Bnum6,Bnum7,Bnum8,Bnum9,Bnum0,clear,enter;
private JLabel Laccount,Lpin,Lcash,Ltake;
private JTextField Taccount, Tpin, Tcash,Ttake;

public Display(){

    JFrame Frame = new JFrame();

    Frame.setTitle("ATM Graphic User Interface");
    Frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Frame.setVisible(true);
    Frame.setSize(600, 400);


    JPanel buttons = new JPanel(new GridLayout(4,4));
    Frame.add(buttons);
    buttons.setVisible(true);
    buttons.setBounds(40, 100, 200, 200);

    JPanel upper = new JPanel(new GridLayout(2,2));
    Frame.add(upper);
    upper.setVisible(true);
    upper.setBounds(40, 20, 350, 50);
    upper.setBackground(Color.cyan);

    JPanel lower = new JPanel(new GridLayout(2,2));
    Frame.add(lower);
    lower.setVisible(true);
    lower.setBounds(270, 100,300, 50);;
    lower.setBackground(Color.CYAN);


    Bnum1 = new JButton("1");
    Bnum2 = new JButton("2");
    Bnum3 = new JButton("3");
    Bnum4 = new JButton("4");
    Bnum5 = new JButton("5");
    Bnum6 = new JButton("6");
    Bnum7 = new JButton("7");
    Bnum8 = new JButton("8");
    Bnum9 = new JButton("9");
    Bnum0 = new JButton("0");
    clear = new JButton("CLEAR");
    enter = new JButton("ENTER");
    Laccount = new JLabel("Account Number  : ");
    Lpin = new JLabel("Pin Number           :");
    Lcash = new JLabel("Transfer Cash");
    Ltake = new JLabel("Take ENV");
    Taccount = new JTextField(15);
    Tpin = new JTextField(15);
    Tcash = new JTextField(5);
    Ttake = new JTextField(5);

    clear.setMargin(new Insets(2,2,2,2));
    enter.setMargin(new Insets(2,2,2,2));

    buttons.add(Bnum1);
    buttons.add(Bnum2);
    buttons.add(Bnum3);
    buttons.add(Bnum4);
    buttons.add(Bnum5);
    buttons.add(Bnum6);
    buttons.add(Bnum7);
    buttons.add(Bnum8);
    buttons.add(Bnum9);
    buttons.add(Bnum0);
    buttons.add(clear);
    buttons.add(enter);
    upper.add(Laccount);
    upper.add(Taccount);
    upper.add(Lpin);
    upper.add(Tpin);
    lower.add(Lcash);
    lower.add(Tcash);
    lower.add(Ltake);
    lower.add(Ttake);



    Bnum1.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum1.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum1.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum2.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum2.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum2.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum3.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum3.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum3.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum4.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum4.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum4.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum5.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum5.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum5.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum6.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum6.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum6.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum7.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum7.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum7.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum8.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum8.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum8.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum9.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum9.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum9.setBackground(UIManager.getColor("control"));
        }
    });
    Bnum0.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            Bnum0.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            Bnum0.setBackground(UIManager.getColor("control"));
        }
    });
    clear.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            clear.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            clear.setBackground(UIManager.getColor("control"));
        }
    });
    enter.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            enter.setBackground(Color.cyan);
        }
        public void mouseExited(java.awt.event.MouseEvent evt) {
            enter.setBackground(UIManager.getColor("control"));
        }
    });










}


}

Answer 1

This may solve your problem. But try to use proper LayoutManager

Add this line

Frame.setLayout(new BorderLayout());

Replace

Frame.add(buttons);
Frame.add(upper);
Frame.add(lower);

By

Frame.add(buttons,BorderLayout.NORTH);
Frame.add(upper,BorderLayout.WEST);
Frame.add(lower,BorderLayout.EAST);

Answer 2

You need to use a LayoutManager for that. For example the BoxLayout fits your needs: Java Documenation about BoxLayout This site also has an example which should get you started. Since you are probably new to LayoutManagers. You should play around with the most simple LayoutManager: FlowLayout FlowLayout will not be the solution to your problem, but will help you understand the concept behind LayoutManagers.

edit: I posted about GridLayout before. But you cannot have a Component spawn multiple cells. So GridLayout is really not what you want.