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Java Swing JButton must create 4 new objects and add to JPanel

Okay, so when I press the JButton menuselect1, I want it to create 4 new objecs, attack1 2 3 and 4, and then add them to the JPanel fightmenu.
This is my code so far, it's a mini pokemon game.
First I create all my objects, and then I set the sizes and adds them to the different JPanels
public class MainFrame extends JFrame {
JPanel mainwindow = new JPanel();
JPanel bottom = new JPanel();
JPanel combat = new JPanel();
JPanel selectionmenu = new JPanel();
JPanel fightmenu = new JPanel();
JButton menuselect1 = new JButton("Fight");
JButton menuselect2 = new JButton("Minimons");
JButton menuselect3 = new JButton("Bag");
JButton menuselect4 = new JButton("Run");
JButton attack1 = new JButton("Tackle");
JButton attack2 = new JButton("Lightningbolt");
JButton attack3 = new JButton("Thunder-Shock");
JButton attack4 = new JButton("Hyper-Beam");
JButton poke1 = new JButton("Ekans");
JButton poke2 = new JButton("Pikachu");
public static void main(String[] args){
new MainFrame();
}
public MainFrame(){
super("MiniMon");
setSize(640,640);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
add(mainwindow);
// SIZES
combat.setPreferredSize(new Dimension(640,452));
bottom.setPreferredSize(new Dimension(640,160));
selectionmenu.setPreferredSize(new Dimension(320,160));
fightmenu.setPreferredSize(new Dimension(320,160));
mainwindow.setLayout(new BorderLayout());
mainwindow.add(combat, BorderLayout.NORTH);
mainwindow.add(bottom, BorderLayout.SOUTH);
combat.setLayout(new BorderLayout());
combat.add(poke1, BorderLayout.NORTH);
combat.add(poke2, BorderLayout.SOUTH);
bottom.setLayout(new BorderLayout());
bottom.add(selectionmenu, BorderLayout.EAST);
bottom.add(fightmenu, BorderLayout.WEST);
selectionmenu.setLayout(new GridLayout(2,2));
selectionmenu.add(menuselect1);
selectionmenu.add(menuselect2);
selectionmenu.add(menuselect3);
selectionmenu.add(menuselect4);
fightmenu.setLayout(new GridLayout(2,2));
setVisible(true);
}
}
I set up my fightmenu to use a 2x2 gridlayout, so I just need to add the 4 objects whenever I press the JButton menuselect1. I'm not really sure how to go about this. I know I should add an eventlistener, but when I tried, it did nothing at all.
I tried doing this:
fightmenu.setLayout(new GridLayout(2,2));
menuselect1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
fightmenupress();
}
private void fightmenupress() {
fightmenu.add(attack1);
fightmenu.add(attack2);
fightmenu.add(attack3);
fightmenu.add(attack4);
}
} );
But it just did nothing.

When you add (or remove) components to a visible GUI, the basic code is:
panel.add(...);
panel.revalidate(); // to invoke the layout manager
panel.repaint(); // to repaint all the components on the panel

I added revalidate and repaint, and it worked!
private void fightmenupress() {
fightmenu.add(attack1);
fightmenu.add(attack2);
fightmenu.add(attack3);
fightmenu.add(attack4);
fightmenu.revalidate();
fightmenu.repaint();
}
} );

JButtons only appear on JFrame if in BorderLayout.CENTER, not SOUTH or NORTH

So I'm trying to create a gui, I've tinkered with gui's before in java but I'm still new to them. So my issued here is that my JLabels (butLabel & cbLabel) are filled with buttons and checkboxes. Sadly my JFrame will only show whichever is set to the BorderLayout.CENTER. NORTH & SOUTH don't ever show, even if I only set the butLabel to SOUTH and don't even use the cbLabel. What am I overlooking?? It's much appreciated, thanks!
public class mainWindow
{
JFrame frame = new JFrame("Main Window");
JLabel butLabel = new JLabel();
JLabel cbLabel = new JLabel();
JButton showBut = new JButton("Show");
JButton exitBut = new JButton("Exit");
JButton addBut = new JButton("Add");
JButton remBut = new JButton("Remove");
JCheckBox aCB = new JCheckBox("Airplane");
JCheckBox bCB = new JCheckBox("Boat");
JCheckBox cCB = new JCheckBox("Clock");
public mainWindow()
{
frame.setLayout(new BorderLayout()); //I know this is set by default to BorderLayout but I just did it when I was out of options to try.
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setMinimumSize(new Dimension(360, 480));
butLabel.setLayout(new GridLayout(1,4));
cbLabel.setLayout(new GridLayout(2, 2));
butLabel.add(showBut);
butLabel.add(exitBut);
butLabel.add(addBut);
butLabel.add(remBut);
cbLabel.add(aCB);
cbLabel.add(bCB);
cbLabel.add(cCB);
frame.add(butLabel, BorderLayout.CENTER);
frame.add(cbLabel, BorderLayout.NORTH);
}
public void setVisible()
{
butLabel.setVisible(true);//Didn't think I needed butLabel.setVisible or the cbLabel.setVisible but
cbLabel.setVisible(true);//again I was trying things that I thought might make sense.
frame.setVisible(true);
}
}

do not use Label for grouping elements, use JPanel instead
I have tried replace all
Label
with
Panel
it works

JScrollPane In JFrame with two panels

I want to add a scroll bar to my JTextArea but it just won't show up. I have read a lot of stuff on forums but all in vain. Any suggestions are highly appreciated.
Thanks in advance. Below is my code.
JPanel pan, pan2;
JTextArea text = new JTextArea();
JTextField fname = new JTextField(18);
JLabel filename = new JLabel("Filename");
JButton view = new JButton("View");
public FileReading() {
setLayout(new BorderLayout());
pan = new JPanel();
pan2 = new JPanel();
JScrollPane scroll = new JScrollPane(text);
//scroll.setBounds(400,400,400,400);
scroll.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
text.setEditable(false);
scroll.setViewportView(text);
pan2.add(scroll);
//scrollpane.setViewportView(text);
pan2.setLayout(new BorderLayout());
//pan2.add(scrollpane);
pan.setLayout(new FlowLayout());
pan.add(filename, FlowLayout.LEFT);
pan.add(fname, FlowLayout.CENTER);
pan.add(view, FlowLayout.RIGHT);
view.addActionListener(this);
fname.addActionListener(this);
pan2.add(text, BorderLayout.CENTER);
pan2.add(pan, BorderLayout.SOUTH);
//BorderLayout.EAST
//add(pan, BorderLayout.SOUTH);
add(pan2);//, BorderLayout.CENTER
setVisible(true);
}
public static void main(String args[]) {
FileReading frame = new FileReading();
frame.setTitle("Enter The Full Path to the File");
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(400,400,400,400);
//frame.setSize(400,400);
}

You need to add scroll (JScrollPane) to the pan2 not to the text (JTextArea)
try this
pan2.add(scroll, BorderLayout.CENTER);
in place of pan2.add(text, BorderLayout.CENTER);
EDIT
JTextArea gets added automatically when we add JScrollPane into the panel, as you have added text (JTextArea) inside JScrollPane
here -> JScrollPane scroll = new JScrollPane(text);

Can try this
add(scroll);//, BorderLayout.CENTER
add(pan, BorderLayout.SOUTH);
instead of
add(pan2);//, BorderLayout.CENTER
This way we are directly adding the scrollpane to main frame and putting other things below

Not all components showing

When I run this program, the window blocks out the buttons in panel2 when I use setSize to determine window size.
In addition, if I use frame.pack() instead of setSize(), all components are on one horizontal line but I'm trying to get them so that panel1 components are on one line and panel2 components are on a line below them.
Could someone explain in detail the answers to both of these problems?
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Exercise16_4 extends JFrame{
// FlowLayout components of top portion of calculator
private JLabel jlbNum1 = new JLabel("Number 1");
private JTextField jtfNum1 = new JTextField(4);
private JLabel jlNum2 = new JLabel("Number 2");
private JTextField jtfNum2 = new JTextField(4);
private JLabel jlbResult = new JLabel("Result");
private JTextField jtfResult = new JTextField(8);
// FlowLayout Components of bottom portion of calculator
private JButton jbtAdd = new JButton("Add");
private JButton jbtSubtract = new JButton("Subtract");
private JButton jbtMultiply = new JButton("Multiply");
private JButton jbtDivide = new JButton("Divide");
public Exercise16_4(){
JPanel panel1 = new JPanel();
panel1.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 3));
panel1.add(jlbNum1);
panel1.add(jtfNum1);
panel1.add(jlNum2);
panel1.add(jtfNum2);
panel1.add(jlbResult);
panel1.add(jtfResult);
JPanel panel2 = new JPanel();
panel2.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 10));
panel1.add(jbtAdd);
panel1.add(jbtSubtract);
panel1.add(jbtMultiply);
panel1.add(jbtDivide);
add(panel1, BorderLayout.NORTH);
add(panel2, BorderLayout.CENTER);
}
public static void main(String[] args){
Exercise16_4 frame = new Exercise16_4();
frame.setTitle("Caculator");
frame.setSize(400, 200);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//frame.setResizable(false);
frame.setVisible(true);
}
}

You're problem is likely a typographical error in that you're adding all components to panel1 and none to panel2:
// you create panel2 just fine
JPanel panel2 = new JPanel();
panel2.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 10));
// but you don't use it! Change below to panel2.
panel1.add(jbtAdd);
panel1.add(jbtSubtract);
panel1.add(jbtMultiply);
panel1.add(jbtDivide);
Add the buttons to panel2, and then call pack() before setVisible(true). Do not set the size of the GUI.

Java Swing Layout

I would like the following lay out...
JButtons on top along side eachother.
The JTextArea should be under the buttons.
The JTextArea should also have a scrollbar.
...for the code below.
JPanel jp = new JPanel();
One = new JButton("One");
Two = new JButton("Two");
TestOutput = new JTextArea();
jp.add(One);
jp.add(Two);
jp.add(TestOutput);

Use a nested layout: To a JPanel having BorderLayout,
add a JPanel having FlowLayout for the buttons to the NORTH
and a JScrollPane for the JTextArea to the CENTER.

The keyword is layering - having JPanel on JPanel.

Use a GridBagLayout
See this for more help : How to Use GridBagLayout
Now note that the JTextarea to have a scrollbar have nothing to do with layouts.
See this for more help in that context : How to Use Scroll Panes

The FlowLayout in a JPanel for the JButton instances is one way to go. You might also use a JToolBar for the buttons.
import java.awt.*;
import javax.swing.*;
class ButtonsAndTextAreaLayout {
ButtonsAndTextAreaLayout() {
JPanel gui = new JPanel(new BorderLayout(5,5));
// use a toolbar for the buttons
JToolBar tools = new JToolBar();
// use firstWordLowerCase for attribute/method names.
JButton one = new JButton("One");
JButton two = new JButton("Two");
tools.add(one);
tools.add(two);
// provide hints as to how large the text area should be
JTextArea testOutput = new JTextArea(5,20);
gui.add(tools, BorderLayout.NORTH);
gui.add(new JScrollPane(testOutput), BorderLayout.CENTER);
JOptionPane.showMessageDialog(null, gui);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonsAndTextAreaLayout();
}
});
}
}

You can either use a GridBagLayout as suggested, or nest multiple layout managers such as:
JFrame frame = new JFrame();
frame.setLayout(new BorderLayout());
JPanel buttonPanel = new JPanel();
JButton oneButton = new JButton("One");
JButton twoButton = new JButton("Two");
buttonPanel.add(oneButton);
buttonPanel.add(twoButton);
JTextArea output = new JTextArea();
JScrollPane scrollPane = new JScrollPane(output);
frame.add(buttonPanel, BorderLayout.NORTH);
frame.add(scrollPane);
frame.pack();
frame.setVisible(true);