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Attempting to set the layout to BoxLayout

I can't seem to find a solution online for why I'm getting this error on attempted run
I'm working on making a simple test system for a different program when are button press will yield value in a text box. I would like them to be on different lines to make it cleaner, so I looked into layouts. I decided a Box Layout would fit me best. I looked at different examples before attempting this and my code ended up looking like this, (apologies for the messy code)
Update
Got the box layout error to disappear but the code will not center them on the panel/frame. The label and button align left while the textfield becomes very large. I don't need it todo that
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import static javax.swing.BoxLayout.Y_AXIS;
import static javax.swing.SwingConstants.CENTER;
public class button extends JFrame {
static JFrame f;
static JButton b;
static JLabel l;
// main class
public static void main(String[] args)
{
// create a new frame to stor text field and button
f = new JFrame("panel");
BoxLayout layout = new BoxLayout(f, BoxLayout.Y_AXIS);
f.setLayout(layout);
// create a label to display text
l = new JLabel("panel label");
b = new JButton("button1");
JTextField textArea = new JTextField(5);
textArea.setEditable(false);
//textArea.append("Hello World");
// create a panel to add buttons
JPanel p = new JPanel();
// add buttons and textfield to panel
f.add(p);
f.setSize(300, 300);
p.add(l);
p.add(b);
p.setBackground(Color.white);
p.add(textArea);
f.show();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Random r = new Random();
textArea.setText(String.valueOf(r));
}
});
}
}
Error
Exception in thread "main" java.awt.AWTError: BoxLayout can't be shared
at java.desktop/javax.swing.BoxLayout.checkContainer(BoxLayout.java:461)
at java.desktop/javax.swing.BoxLayout.invalidateLayout(BoxLayout.java:245)
at java.desktop/javax.swing.BoxLayout.addLayoutComponent(BoxLayout.java:278)
at java.desktop/java.awt.Container.addImpl(Container.java:1152)
at java.desktop/java.awt.Container.add(Container.java:1029)
at java.desktop/javax.swing.JFrame.addImpl(JFrame.java:553)
at java.desktop/java.awt.Container.add(Container.java:436)
at button.main(button.java:36)
I would like the three items to all to be stacked one on top of another with a space between them. The order doesn't matter right now.

Swing was first added to the JDK in 1998 and has undergone a lot of changes since. Unfortunately, when you read Web pages about Swing, it is not obvious when that page was last updated. Consequently you may be learning outdated techniques for writing Swing code.
First of all, according to the code you posted, class button does not need to extend class JFrame since you use a static variable as your application's JFrame. Also, JFrame is a top-level container which makes it a special kind of container and not the same kind of continer as a JPanel. You need to set the layout manager for your JPanel and then add the JLabel, JTextField and JButton to that JPanel. And then add the JPanel to the JFrame.
Calling method pack() of class JFrame will automatically set the preferred sizes for the components inside the JFrame. It appears in the code below.
Please also look at Java coding conventions which allows others to more easily read and understand your code. And note that, according to these conventions, I renamed your class from button to Buttons and also because there are already several class in the JDK named Button.
Here is my rewrite of your code...
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.WindowConstants;
public class Buttons implements Runnable {
public void run() {
createAndShowGui();
}
private void createAndShowGui() {
JFrame f = new JFrame("Box");
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel p = new JPanel();
BoxLayout layout = new BoxLayout(p, BoxLayout.Y_AXIS);
p.setLayout(layout);
JLabel l = new JLabel("panel label");
JTextField textField = new JTextField(5);
JButton b = new JButton("button1");
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Random r = new Random();
textField.setText(String.valueOf(r.nextBoolean()));
}
});
p.add(l);
p.add(textField);
p.add(b);
f.add(p);
f.pack();
f.setLocationByPlatform(true);
f.setVisible(true);
}
public static void main(String[] args) {
Buttons instance = new Buttons();
EventQueue.invokeLater(instance);
}
}

To add Scroller in JFrame which have JPanel Dynamic

I have two files, one is Main.java and the second is frame.java.
I'm creating a desktop application so I want to add scrollpane as needed vertically or horizontally in Main.java file.
Frame.java throws the JPanel object which is being catched by Main.java and dynamically loaded into JFrame.
So anyone please tell me, how can I add the scrollpane or scrollbar. Which is best, I don't know. Thank you..
Main.java:
package pack;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
public static void main(String[] args) {
JPanel pn = null;
JFrame mainFrame = null;
frame login = new frame();
mainFrame = new JFrame("Prem");
mainFrame.setLayout(new BorderLayout());
mainFrame.setDefaultCloseOperation(mainFrame.EXIT_ON_CLOSE);
mainFrame.setSize(500,500);
mainFrame.setLocationRelativeTo(null);
pn=login.getLogin();
mainFrame.add(pn,BorderLayout.CENTER);
mainFrame.setVisible(true);
}
public Main() {
super();
}
}
This is second file which throws the panel object from method frame.java
package pack;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.AbstractAction;
import java.awt.*;
import java.awt.event.*;
public class frame {
JPanel pane = null,pane1=null;
JTextField userText=null,passText=null;
JLabel userLabel =null,passLabel=null,errorLabel=null;
JButton submitLogin = null;
public frame()
{
pane = new JPanel();
pane.setLayout(null);
}
public JPanel getLogin()
{
userLabel = new JLabel("UserName");
pane.add(userLabel);
userLabel.setBounds(5,10,100, 30);
userText = new JTextField();
pane.add(userText);
userText.setBounds(110,10,120,30);
passLabel = new JLabel("PassWord");
pane.add(passLabel);
passLabel.setBounds(5,60,100, 30);
passText = new JTextField();
pane.add(passText);
passText.setBounds(110,60,120,30);
errorLabel = new JLabel("");
pane.add(errorLabel);
errorLabel.setBounds(5,150,180,30);
submitLogin = new JButton("Submit");
pane.add(submitLogin);
submitLogin.setBounds(80,110,90,30);
submitLogin.addActionListener(new AbstractAction(){
public void actionPerformed(ActionEvent e)
{
if(submitLogin.getActionCommand() == "Submit")
{
if(userText.getText().isEmpty() || passText.getText().isEmpty())
{
errorLabel.setText("Enter UserName And Password");
}
else
{
//connection
}
}
else
{
System.exit(0);
}
}
});
return pane;
}
}

You have several issues with that code including:
You don't show us in your code where you're trying to use a JScrollPane or even where it's needed. If you show us your attempt to use this, we'll get a much better understanding of your problem.
You are using a null layout and setBounds(...), something you should avoid at almost all costs, and something which absolutely must be avoided if you want to use a JScrollPane, since JScrollPane's do not work well with null layouts. Instead read up on and use layout managers.
You're comparing Strings using the == operator. You don't want to compare Strings using ==. Use the equals(...) or the equalsIgnoreCase(...) method instead. Understand that == checks if the two objects are the same which is not what you're interested in. The methods on the other hand check if the two Strings have the same characters in the same order, and that's what matters here.
You can find links to the Swing tutorials and other Swing resources here: Swing Info
You can find the layout manager tutorial here: Layout Manager Tutorial.
You can learn about "nesting" layouts here.
You can find specific information on how to use JScrollPanes here: JScrollPane Tutorial.
The basic use of them is that you will want to add your scrollable component to the JScrollPane's viewport, and then add the JScrollPane to the GUI. The specifics of how to do this will all depend on your needs, something we don't yet know, but again is very well explained in the tutorials that I've linked to above.

JPanel size not being set

I'm currently working on an irc bot and today I would like to create a GUI for it.
I'm trying to create a column layout that has two parts, left and right.
The left side will show console output, the right will contain all the controls (joining channels, commands etc).
I'm having issues creating the two columns. I have a JPanel that is the whole width and height of the window and has a border of 10 pixels, and then I have two panels within that; left and right.
The left and right panels are for some reason taking the whole size of the window, and the right panel is overlapping everything.
Here's an example picture: http://i.imgur.com/lc4vHVH.png
The white is the right panel, it should only be half the size and have an identical but black panel on the left of it.
Here's my current code, sorry if it's messy, new to the whole Swing GUI.. Thanks for any help.
package tk.TaylerKing.GribbyBot;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import java.util.HashMap;
import javax.swing.BorderFactory;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import com.alee.laf.WebLookAndFeel;
import com.alee.laf.menu.WebMenuBar;
import com.alee.laf.menu.WebMenuItem;
import com.alee.laf.panel.WebPanel;
import com.alee.laf.rootpane.WebFrame;
public class GribbyBot extends WebFrame {
private static final long serialVersionUID = 4641597667372956773L;
public static HashMap<String, ArrayList<String>> connections = new HashMap<String, ArrayList<String>>();
public static void main(String[] args) throws Exception {
UIManager.setLookAndFeel(WebLookAndFeel.class.getCanonicalName());
SwingUtilities.invokeLater(new Runnable(){
public void run(){
GribbyBot gb = new GribbyBot();
gb.setVisible(true);
}
});
}
public GribbyBot(){
WebPanel panel = new WebPanel();
panel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
panel.setPreferredSize(new Dimension(780, 580));
WebMenuBar menu = new WebMenuBar();
WebMenuItem file = new WebMenuItem("Exit");
file.setMnemonic(KeyEvent.VK_E);
file.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
});
menu.add(file);
setJMenuBar(menu);
WebPanel left = new WebPanel();
left.setPreferredSize(new Dimension(380, 580));
left.setBackground(Color.BLACK);
WebPanel right = new WebPanel();
right.setPreferredSize(new Dimension(380, 580));
right.setBackground(Color.WHITE);
add(panel);
panel.add(left);
panel.add(right);
setTitle("GribbyBot");
setSize(800, 600);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setResizable(false);
}
}
On a side note, all the variables that are prefixed with "Web" are the same as Swing, but it's a custom GUI.

Override JComponent#getPreferredSize() instead of using setPreferredSize()
Read more Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?
If extremely needed in case of Performing Custom Painting then try in this way:
Sample code:
final JPanel panel = new JPanel(){
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
// your custom painting code here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(40, 40);
}
};
Why are using setPreferredSize() method whereas you can achieve this design easily using any proper layout such as BoxLayout, GridLayout, BorderLayout etc.
Read more about layout How to Use Various Layout Managers
EDIT
try JPanel panel = new JPanel(new GridLayout(1,2));

How to implement layout?

I have a GUI program which includes JLabels and JButtons and basically I want a layout that would help me display them as follows:
Label1 Button1
Label2 Button2
Label3 Button3
.....
Is there a layout that would allow me to achieve the above result?
I have looked at this example but is too complex and was wondering if there is anything automated that I can use?

This is one of the few things for which I'd recommend (a utility method and) GroupLayout as seen in this answer.

You can use GridLayout. Documentation here.

This is just for simplicity, and for your question. GUI is really dependent on what you would like to do and is really a thing that can be hardly automated..., and i don't think you only want those 6 elements on your GUI, but theoretically this will do it:
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class GUITest {
private Box labelbox = new Box(BoxLayout.Y_AXIS);
//Y_AXIS means they are placed vertically in the box
private Box buttonbox = new Box(BoxLayout.Y_AXIS);
private JFrame frame = new JFrame();
private JPanel panel = new JPanel();
public void makeGUI1() {
for (int i = 1; i <= 3; i++) {
//if you want to save the references, you should make
//an ArrayList<JLabel> and add each of them to it
JLabel label = new JLabel("Label " + i);
labelbox.add(Box.createVerticalStrut(5));
//these are for giving the labels some extra space
//between them vertically to be in line with the buttons
labelbox.add(label);
labelbox.add(Box.createVerticalStrut(10)); //these are too
}
for (int i = 1; i <= 3; i++) {
//if you want to save the references, you should make
//an ArrayList<JButton> and add each of them to it
JButton button = new JButton("Button " + i);
buttonbox.add(button);
}
panel.add(labelbox, BorderLayout.EAST);
//you can find picture of each constant:
//http://download.java.net/jdk7/archive/b123/docs/api/java/awt/BorderLayout.html
panel.add(buttonbox, BorderLayout.WEST);
frame.add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
GUITest guitest = new GUITest();
guitest.makeGUI1();
}
});
}
}

You can also use obj.setBounds(LeftSpaceParameter,TopSpaceParameter) with which you can place the gui elements or objects at any position of your choice. You need to put the default layout to null
yet gridLayout is much easier. .

Creating Gridbag Layout

I'm trying to make a gridbaglayout, to simply have the label atop the textbox atop the textview in a vertical window, but I'm getting the exception
Exception in thread "main" java.lang.IllegalArgumentException: cannot add to layout: constraints must be a GridBagConstraint
at java.awt.GridBagLayout.addLayoutComponent(GridBagLayout.java:685)
at java.awt.Container.addImpl(Container.java:1072)
at java.awt.Container.add(Container.java:957)
at javax.swing.JFrame.addImpl(JFrame.java:540)
at java.awt.Container.add(Container.java:925)
at guiprojj.gui.main(gui.java:31)
Can anyone assist me in fixing this exception, maybe I'm misunderstanding how gridbaglayout works, if so, if you could point me in the right direction that would be awesome.
Appreciate the assistance.
package guiprojj;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Map;
import javax.swing.*;
import com.eclipsesource.json.JsonObject;
import com.google.gson.JsonParser;
import com.json.parsers.JSONParser;
import com.json.parsers.JsonParserFactory;
public class gui {
public static void main(String[] args)
{
JFrame maingui = new JFrame("Gui");
maingui.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.HORIZONTAL;
JButton enter = new JButton("Enter");
final JTextArea movieinfo = new JTextArea(5,20);
final JTextField movietext = new JTextField(16);
c.gridx = 1;
c.gridy = 0;
maingui.add(movietext, maingui);
final JScrollPane scrolll = new JScrollPane(movieinfo);
final JLabel titlee = new JLabel("Enter movie name here:");
maingui.setResizable(false);
maingui.setVisible(true);
movieinfo.setLineWrap(true);
movieinfo.setWrapStyleWord(true);
movieinfo.setEditable(false);
scrolll.getPreferredSize();
//pangui.setPreferredSize(new Dimension(300, 150));
//pangui.add(scrolll, BorderLayout.CENTER);
//movieinfo.add(scrolll);
maingui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
maingui.pack();
enter.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e)
{
System.out.println(Test.getMovieInfo(movietext.getText()));
JsonParserFactory factory=JsonParserFactory.getInstance();
JSONParser parser=factory.newJsonParser();
Map jsonData=parser.parseJson(Test.getMovieInfo(movietext.getText()));
String Title = (String)jsonData.get("Title");
String Year = (String)jsonData.get("Year");
String Plot = (String)jsonData.get("Plot");
movieinfo.setText("Title: "+Title+"\nYear: "+ Year +"\nPlot: "+Plot);
}
});
}
}

I think maingui.add(movietext, maingui); should be maingui.add(movietext, c);
That last parameter should be the layout-specific constraints object. You're passing it the parent object.

maingui.add(movietext, maingui);
"maingui" is NOT a GridBagConstraint. "c" IS A GridBagConstraint.
I don't know if using the proper variable will correct the layout, but it should get rid of the Exception. Read the Swing tutorial on How to Use GridBagLayout for examples. Not only that you will find code to better structure your program. All GUI code should execute on the EDT. Read the tutorial section on Concurrency for more information on that.

This is wrong:
maingui.add(movietext, maingui);
When you add to a container, you add the Component + its constraints. In your case:
maingui.add(movietext, c);