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Java JScrollPane ve

I want to make a Java-Code, where I can insert as many Panels as I want. So that I can scroll down to see the Panels. I'm so far right now:
But my problem is, I can't scroll down. I tested the JScrollPane with JTextAreas which worked just fine.
Picture of my Program
package test;
import java.awt.*;
import javax.swing.*;
public class Scrollbar {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JPanel panel3 = new JPanel();
JTextField tFId = new JTextField("ID: ", 5);
JTextField tFName = new JTextField("Name: ", 5);
JTextField tFHersteller = new JTextField("Hersteller: ", 5);
JTextField tFId2 = new JTextField("ID: ", 5);
JTextField tFName2 = new JTextField("Name: ", 5);
JTextField tFHersteller2 = new JTextField("Hersteller: ", 5);
JTextField tFId3 = new JTextField("ID: ", 5);
JTextField tFName3 = new JTextField("Name: ", 5);
JTextField tFHersteller3 = new JTextField("Hersteller: ", 5);
frame.setSize(400, 400);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new FlowLayout());
panel.setLayout(new FlowLayout());
panel.setPreferredSize(new Dimension(200, 85));
panel.add(panel1);
panel.add(panel2);
panel.add(panel3);
JScrollPane scrollPanel = new JScrollPane(panel, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
panel1.setLayout(new FlowLayout());
panel1.add(tFId);
panel1.add(tFName);
panel1.add(tFHersteller);
panel2.setLayout(new FlowLayout());
panel2.add(tFId2);
panel2.add(tFName2);
panel2.add(tFHersteller2);
panel3.setLayout(new FlowLayout());
panel3.add(tFId3);
panel3.add(tFName3);
panel3.add(tFHersteller3);
frame.add(scrollPanel);
frame.setVisible(true);
}
}

You are over-using FlowLayout.
Different layouts have diferent behaviors. First, you need to remove this line:
frame.setLayout(new FlowLayout());
The default layout for a frame’s content pane is a BorderLayout. You want to leave it that way, because a component added to a BorderLayout with no constraints will be placed in the center, where it will stretch to fill the entire space.
Second, you want to remove these:
panel.setLayout(new FlowLayout());
panel.setPreferredSize(new Dimension(200, 85));
Setting the preferred size interferes with the JScrollPane’s ability to manage its view (that is, panel). When you want to have your components appear on multiple rows, you should try to force FlowLayout to do it by constraining its width; rather, use a layout that is designed to place components on different rows. The best choice is GridBagLayout:
panel.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
panel.add(panel1, gbc);
panel.add(panel2, gbc);
gbc.weighty = 1;
gbc.anchor = GridBagConstraints.NORTH;
panel.add(panel3, gbc);
The use of GridBagConstraints.REMAINDER in a constraint will tell the GridBagLayout to make a child component take up an entire row.
The use of weighty = 1 tells the GridBagLayout that the grid cell of the child about to be added should take up all extra vertical space, when the panel is larger than its children. Finally, GridBagConstraints.NORTH keeps that child placed at the top of that stretched grid cell, no matter how high the grid cell is.

Java BoxLayout use full width

I am creating a messaging program that has multiple chats. On the side of the chat window there is a JPanel containing a List Array of all the buttons to switch chats.I am having trouble getting all the buttons in the side panel to be the same width, no matter what they contain. But whatever I try doesn't seem to work and I am looking for some help. Please can you explain what the code does and how it can be used so I can learn it for next time. Sorry if the comments aren't the best it's a work in progress as I wait till code works before adding detailed comments otherwise I am constantly changing them. :(
This is what it looks like without any chats:
This is with multiple chats and you can see the width variation
Here is the code that is run when a new user is added:
public void newUser() {
JPanel dialogue = new JPanel();
dialogue.setLayout(new BoxLayout(dialogue, BoxLayout.Y_AXIS));
//Creating/adding dialogue components
JLabel Enter_ip = new JLabel("Enter the ip address");
JTextField Get_ip = new JTextField("");
dialogue.add(Enter_ip);
dialogue.add(Get_ip);
dialogue.add(Box.createHorizontalStrut(15));
JLabel Enter_name = new JLabel("Enter the user's name");
JTextField Get_name = new JTextField("");
dialogue.add(Enter_name);
dialogue.add(Get_name);
//Creating the dialogue box
JOptionPane.showConfirmDialog(null, dialogue, "New User", JOptionPane.OK_CANCEL_OPTION);
//Getting data from dialogue box
String ip = Get_ip.getText();
String name = Get_name.getText();
//Try connecting to other user here
//Adding user message data
int size = Users_Messages_Data.size();
Users_Messages_Data.add(new ArrayList());//New user
Users_Messages_Data.get(size).add(new ArrayList());//Messages
Users_Messages_Data.get(size).add(new ArrayList());//Details
Users_Messages_Data.get(size).get(1).add(name);
Users_Messages_Data.get(size).get(1).add(ip);
Users_Messages_Data.get(size).get(1).add("port number");
//adds new UserButton
int temp = users.size();
users.add(new JButton(Users_Messages_Data.get(size).get(1).get(0)));
users.get(temp).addActionListener(this);
users.get(temp).setSize(new Dimension(500, 500));
SelectUser.add(users.get(temp), gbc);
Messaging.revalidate();
pack();
}
and here is the initialisation method:
public void MessagingGUI() {
//Creates JFrame and pane
Messaging = new JFrame();
Container pane = getContentPane();
JLabel info = new JLabel("29/07/2016 15:36");
//Creates user chats panel
SelectUser = new JPanel(new GridBagLayout());
gbc = new GridBagConstraints();
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = GridBagConstraints.REMAINDER;
SelectUser.setLayout(new BoxLayout(SelectUser, BoxLayout.Y_AXIS));
SelectUser.setSize(new Dimension(500, 500));
//Adds different chats
users = new ArrayList<JButton>();
int x;
for (x = 0; x < Users_Messages_Data.size(); x++) {
users.add(new JButton(Users_Messages_Data.get(x).get(1).get(0)));
users.get(x).addActionListener(this);
SelectUser.add(users.get(x), gbc);
}
JButton newUser = new JButton("+");
newUser.addActionListener(this);
SelectUser.add(newUser);
JScrollPane UserScroll = new JScrollPane(SelectUser,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//Creates messages feed
JPanel Messages = new JPanel();
Messages.setLayout(new BoxLayout(Messages, BoxLayout.Y_AXIS));
AllMessages = new JTextArea(10, 30);
AllMessages.setBackground(Color.WHITE);
AllMessages.setEditable(false);
AllMessages.setBorder(BorderFactory.createLineBorder(Color.BLUE, 1));
JScrollPane MessageScroll = new JScrollPane(AllMessages,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//Creates user text entry box
UserText = new JTextArea(5, 30);
//UserText.setLineWrap(true);
//UserText.setWrapStyleWord(true);
UserText.setBorder(BorderFactory.createLineBorder(Color.CYAN, 1));
UserText.setText("Enter Message. Press enter to send");
UserText.setFocusable(true);
UserText.addKeyListener(this);
UserText.setPreferredSize(new Dimension(5, 20));
//Adds all components to pane
Messages.add(info);
Messages.add(MessageScroll);
Messages.add(UserText);
pane.add(UserScroll, BorderLayout.WEST);
pane.add(Messages, BorderLayout.CENTER);
//JFrame setup
Messaging.setTitle("Messaging");
Messaging.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Messaging.setContentPane(pane);
Messaging.setVisible(true);
Messaging.setSize(400, 350);
Load_User(current_user);
}

First of all, variable names should NOT start with an upper case character. Some of your variable names are correct, other are not. Be consistent and follow Java conventions!!!
.I am having trouble getting all the buttons in the side panel to be the same width,
Don't use a BoxLayout. It does not automatically resize on the opposite axis of the layout.
Instead you can use:
a GridLayout to make all the buttons the same size. The GridLayout will also fill the area vertically which is not what you want so you will need to nest panels. So create a parent panel using a BorderLayout. Add your panel using the GridLayout with the buttons to the BorderLayout.PAGE_START of this parent panel. Then add the BorderLayout panel to the scroll pane.
a GridBagLayout. You will need to use the "fill" contstraint to have the component fill the width of the cell.
Read the Swing tutorial on Layout Managers for more information and examples.
Or maybe a different approach is to use a JList to display the users.

JTextArea stretches when setWrapLine

I have the following code: the problem is that when i run the application, the JPanel containing those components stretches because of setLineWrap(true) I've inserted the JTextArea in a JScrollPane as suggested here
http://docs.oracle.com/javase/tutorial/uiswing/components/textarea.html
but with no result
titolo=new JLabel("title");
text=new JTextArea("");
scrollPane = new JScrollPane(text);
text.setLineWrap(true);
griglia=new GridBagLayout();
gbc=new GridBagConstraints();
setLayout(griglia);
buildConstraints(gbc,0,0,1,1,100,1);
griglia.setConstraints(titolo,gbc);
buildConstraints(gbc,0,1,1,1,100,100);
griglia.setConstraints(scrollPane,gbc);
add(titolo);
add(scrollPane);

Check GridBagConstraint here in the fill - The initial fill value use GridBagConstraints.NONE.

how do you increase panel width?

With this code I will have the following window. I created 2 panels and added the mainp one to the frame and the panel to the mainp I did this in order to make window resizing dynamic (so the panel wont resize to the frame) I tried making my default panel size wider so that the text fields and label become wider but panel.setsize doesn't seem to do anything.
// creates the labels
studId = new JLabel("Student ID");
studAvg = new JLabel("Student Average");
studName = new JLabel("Student Name");
// creates the text fields
JTextField studIdText = new JTextField();
JTextField studAvgText = new JTextField();
JTextField studNameText = new JTextField();
JPanel mainp = new JPanel();
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(3, 2, 2, 2));
panel.setSize(300, 100);
// adds to the GridLayout
panel.add(studId);
panel.add(studIdText);
panel.add(studName);
panel.add(studNameText);
panel.add(studAvg);
panel.add(studAvgText);
mainp.add(panel);
add(BorderLayout.CENTER,mainp);
// verifies the textfields
studIdText.setInputVerifier(new IntVerifier());
studAvgText.setInputVerifier(new DoubleVerifier());
setTitle("Student Form");
setSize(300, 200);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);

The method you are looking for is setPreferredSize. Use it instead of panel.setSize(300, 100).
panel.setPreferredSize(new Dimension(300, 100));
I would also recommend to not setting the size of your JFrame to the fixed value (300,200) but do pack() instead. This will set the size of your JFrame to fit the panels inside.

using Advise from #Dan and #MADprogrammer and #trashgod i came up with the following
JTextField studIdText = new JTextField(20);
JPanel panel = new JPanel();
panel.setLayout(new GridBagLayout());
GridBagConstraints r1 = new GridBagConstraints();
r1.fill = GridBagConstraints.HORIZONTAL;
r1.weightx = 0.0;
r1.gridx = 0;
r1.gridy = 0;
panel.add(studId,r1);
r1.weightx = 0.5;
r1.gridx = 1;
r1.gridwidth = GridBagConstraints.REMAINDER;
panel.add(studIdText,r1);
of course you can make GridBagConstraints for every row and just change the gridy

Set the layout for mainp as BorderLayout.
mainp.setLayout(new BorderLayout());
Then, in order to avoid having the textfields resize vertically and look strange, you can add panel to BorderLayout.NORTH, for instance.
mainp.add(panel, BorderLayout.NORTH);

Adding a label for a JTextField

I have a JTextField and I want to add a label next to it, so that it looks like this...
+---------------+
TEAM 1: |Text field here|
+---------------+
This is the code where I am constructing the JTextFields...
jb = new JButton(">> FIGHT <<");
jt0 = new JTextField("", 25);
jt1 = new JTextField("", 25);
jt2 = new JTextField("<< BATTLE VICTOR >>", 35);
Could someone please tell me how to add the label.

Just put a JLabel next to your JTextField.

In addition to layout selection, don't forget that "you can improve your program's accessibility by using the setLabelFor() method," as discussed in How to Use Labels.

If you want to add any text to your interface, you should use JLabel. By placing a JLabel next to a JTextField, you can achieve the look you are asking for.
A JLabel is simply constructed like this...
JLabel myLabel = new JLabel("This is my message");
The way you add the JLabel to your interface depends on your JPanel/JFrame layout, but I tend to prefer BorderLayout, which you would use like this...
JLabel myLabel = new JLabel("Team 1");
JTextField myTextField = new JTextField("Team Awesome!");
JPanel panel = new JPanel(new BorderLayout());
panel.add(myLabel,BorderLayout.WEST);
panel.add(myTextField,BorderLayout.CENTER);
This will put a JLabel to the left (WEST) of the JTextField.
Refer to the following documentation for more information:
JLabel: http://docs.oracle.com/javase/6/docs/api/javax/swing/JLabel.html
BorderLayout: http://docs.oracle.com/javase/6/docs/api/java/awt/BorderLayout.html

You want to use a combination of a layout manager and JLabels
JLabel label = new JLabel("User name:");
JTextField field = new JTextField(12);
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
add(label, gbc);
gbc.grid++;
add(field, gbc);
Check out How to Use Labels for more examples