Display a JPanel

[Jenny]

Hi All,

I have two code. Could you tell me why first one hide the JPanel
initially but second one does not? Pleaes run them and see the
result. Thanks a lot

Jenny

First:
import java.awt.*;
import javax.swing.*;
public class Mango {
public static void main(String[] args) {
JFrame f = new JFrame("The Frame");
f.setLocation(100, 100);
Container content = new JPanel( );
content.add(new JLabel("Mango"));
content.add(new JButton("Mango"));
f.setContentPane(content);
f.setVisible(true);
}
}

second:

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

public class LottoMadness extends JFrame {

// set up row 1
JPanel row1 = new JPanel();
ButtonGroup option = new ButtonGroup();
JCheckBox quickpick = new JCheckBox("Quick Pick", false);
JCheckBox personal = new JCheckBox("Personal", true);
// set up row 2
JPanel row2 = new JPanel();
JLabel numbersLabel = new JLabel("Your picks ", JLabel.RIGHT);
JTextField[] numbers = new JTextField[6];
JLabel winnersLabel = new JLabel("Winners ", JLabel.RIGHT);
JTextField[] winners = new JTextField[6];
// set up row 3
JPanel row3 = new JPanel();
JButton stop = new JButton("Stop");
JButton play = new JButton("Play");
JButton reset = new JButton("Reset");
// set up row 4
JPanel row4 = new JPanel();
JLabel got3Label = new JLabel("3 of 6 ", JLabel.RIGHT);
JTextField got3 = new JTextField();
JLabel got4Label = new JLabel("4 of 6 ", JLabel.RIGHT);
JTextField got4 = new JTextField();
JLabel got5Label = new JLabel("5 of 6 ", JLabel.RIGHT);
JTextField got5 = new JTextField();
JLabel got6Label = new JLabel("6 of 6 ", JLabel.RIGHT);
JTextField got6 = new JTextField(10);
JLabel drawingsLabel = new JLabel("Drawings ", JLabel.RIGHT);
JTextField drawings = new JTextField();
JLabel yearsLabel = new JLabel("Years ", JLabel.RIGHT);
JTextField years = new JTextField();

public LottoMadness() {
super("Lotto Madness");
setSize(550, 270);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
GridLayout layout = new GridLayout(5, 1, 10, 10);
Container pane = getContentPane();
pane.setLayout(layout);

FlowLayout layout1 = new FlowLayout(FlowLayout.CENTER,
10, 10);
option.add(quickpick);
option.add(personal);
row1.setLayout(layout1);
row1.add(quickpick);
row1.add(personal);
pane.add(row1);

GridLayout layout2 = new GridLayout(2, 7, 10, 10);
row2.setLayout(layout2);
row2.setLayout(layout2);
row2.add(numbersLabel);
for (int i = 0; i < 6; i++) {
numbers = new JTextField();
row2.add(numbers);
}
row2.add(winnersLabel);
for (int i = 0; i < 6; i++) {
winners = new JTextField();
winners.setEditable(false);
row2.add(winners);
}
pane.add(row2);

FlowLayout layout3 = new FlowLayout(FlowLayout.CENTER,
10, 10);
row3.setLayout(layout3);
stop.setEnabled(false);
row3.add(stop);
row3.add(play);
row3.add(reset);
pane.add(row3);

GridLayout layout4 = new GridLayout(2, 3, 20, 10);
row4.setLayout(layout4);
row4.add(got3Label);
got3.setEditable(false);
row4.add(got3);
row4.add(got4Label);
got4.setEditable(false);
row4.add(got4);
row4.add(got5Label);
got5.setEditable(false);
row4.add(got5);
row4.add(got6Label);
got6.setEditable(false);
row4.add(got6);
row4.add(drawingsLabel);
drawings.setEditable(false);
row4.add(drawings);
row4.add(yearsLabel);
years.setEditable(false);
row4.add(years);
pane.add(row4);
setContentPane(pane);
setVisible(true);
}

public static void main(String[] arguments) {
LottoMadness frame = new LottoMadness();
}
}

 

[Andrew Thompson]

Could you tell me why first one hide the JPanel
initially but second one does not?

Dunno.. But I noticed you did not call
validate() on either if them..

Try that at the end of the constructor and
see if the behaviour changes..

HTH

BTW, do you realize that another group
concentrates on GUI matters?
<http://www.physci.org/codes/javafaq.jsp#cljg>

 

[andrewh1]

Hi All,

I have two code. Could you tell me why first one hide the JPanel
initially but second one does not? Pleaes run them and see the
result. Thanks a lot

Jenny

First:
import java.awt.*;
import javax.swing.*;
public class Mango {
public static void main(String[] args) {
JFrame f = new JFrame("The Frame");
f.setLocation(100, 100);

try adding

f.setSize(550, 270);

which is the line taken from your "LottoMadness" class.

 

[Jenny]

Thanks a lot.