Develop Reference

How to update Jpanel using JComboBox

i'm new in java language, and i'm trying to create a GUI which it has JComboBox to allow the user to select one of the choices and based on the selected option the panel is updated by adding more text fields.
currently i'm facing an issue which is the panel doesn't updated if I choosed (choice 1) it should appear 5 text fields with their labels.
My question is: how can I update the panel to add more text fields based on the selected option from JComboBox by the user?
Also, I'm facing another issue which i couldn't find a way to setting the size of JFrame
Here is my code:
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class RTSS extends JFrame implements ActionListener {
private JComboBox cb;
JPanel main;
JPanel panel3;
JPanel panel2;
JPanel panel1;
GridBagConstraints gbc;
String[] choices;
JLabel Label1;
JLabel Label2;
JLabel Label3;
JLabel Label4;
JLabel Label5;
JTextField tf1;
JTextField tf2;
JTextField tf3;
JTextField tf4;
JTextField tf5;
public RTSS() {
Border blackline = BorderFactory.createLineBorder(Color.black);
EmptyBorder b1 = new EmptyBorder(5, 0, 0, 0);
main = new JPanel(new FlowLayout(FlowLayout.LEFT));
panel3 = new JPanel(new FlowLayout(FlowLayout.LEFT));
panel3.setAlignmentX(1);
panel3.setPreferredSize(new Dimension(800, 35));
panel3.setBorder(b1);
main.add(panel3);
panel2 = new JPanel();
panel1 = new JPanel();
panel1.setPreferredSize(new Dimension(700, 500));
panel1.setBorder(blackline);
panel1.setLayout(new GridBagLayout());
gbc = new GridBagConstraints();
choices = new String[]{ "","Choice 1", "Choice 2", "Choice 3 "};
cb = new JComboBox(choices);
//Main inputs (labels)
Label1 = new JLabel("Label 1 ");
Label2 = new JLabel("Label 2 ");
Label3 = new JLabel("Label 3");
Label4 = new JLabel("Label 4 ");
Label5 = new JLabel("Label 5 ");
//TextFields
tf1 = new JTextField(10);
tf2 = new JTextField(10);
tf3 = new JTextField(10);
tf4 = new JTextField(10);
tf5 = new JTextField(10);
gbc.anchor = GridBagConstraints.NORTHWEST;
gbc.weightx = 0;
gbc.weighty = 0;
gbc.insets = new Insets(10, 3, 5, 0);
panel3.add(cb);
panel2.add(panel1);
gbc.gridx = 0;
gbc.gridy = 0;
panel1.add(Label1, gbc);
gbc.gridx = 0;
gbc.gridy = 1;
panel1.add(Label2, gbc);
gbc.gridx = 0;
gbc.gridy = 2;
panel1.add(Label3, gbc);
gbc.gridx = 1;
gbc.gridy = 0;
panel1.add(tf1, gbc);
gbc.gridx = 1;
gbc.gridy = 1;
panel1.add(tf2, gbc);
gbc.weightx = 0.5;
gbc.weighty = 0.5;
gbc.gridx = 1;
gbc.gridy = 2;
panel1.add(tf3, gbc);
main.add(panel2);
add(main);
}
#Override
public void actionPerformed(ActionEvent e) {
String Choice = cb.getSelectedItem().toString();
if ("Choice 1".equals(Choice)) {
gbc.gridx = 0;
gbc.gridy = 3;
panel1.add(Label4, gbc);
gbc.gridx = 1;
gbc.gridy = 3;
panel1.add(tf4, gbc);
gbc.gridx = 0;
gbc.gridy = 4;
panel1.add(Label5, gbc);
gbc.weightx = 6;
gbc.weighty = 1;
gbc.gridx = 1;
gbc.gridy = 4;
panel1.add(tf5, gbc);
}
}
public static void main(String[] args) {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
ex.printStackTrace();
}
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new RTSS().setVisible(true);
}
});
}
}

Add the following lines to the end of the RTSS constructor:
public RTSS() {
//your code
//this lines
pack();
setLocationRelativeTo(null);
cb.addActionListener(this);
}
These 3 lines will 1.set the layout, 2. center the frame and 3. activate the ActionListener.
If you now make a selection in the ComboBox, your code will be executed in the ActionListener.
After a selection in the ComboBox that changes the layout, call pack() again.
#Override
public void actionPerformed(ActionEvent e) {
String Choice = cb.getSelectedItem().toString();
if ("Choice 1".equals(Choice)) {
// your code
pack();
}
}

Variable not found even though it's in the class above

So I have a GUI class which contains the JButtons, and then I have an actionPerformed class below which shows what will happen if I press the button. Now, when I do the if(e.getSource()==search) the search comes up red and says the variable cannot be found in the class GUI. Even though it's in that very class.
I need some help with this.
package crimedata;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
class GUI extends JFrame implements ActionListener {
Connection con = null;
GUI() {
JPanel p = new JPanel();
JFrame f = new JFrame("Crime Data");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(600, 600);
f.setResizable(true);
f.setLocationRelativeTo(null);
GridBagConstraints gbc = new GridBagConstraints();
getContentPane().setLayout(new GridBagLayout());
gbc.insets = new Insets(5, 5, 5, 5);
JLabel LongLabel = new JLabel("Enter Longitude here");
LongLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 1;
getContentPane().add(LongLabel, gbc);
JTextField LongText = new JTextField(20);
getContentPane().add(LongText, gbc);
JLabel LatLabel = new JLabel("Enter Latitude here");
LatLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 2;
getContentPane().add(LatLabel, gbc);
JTextField LatText = new JTextField(20);
getContentPane().add(LatText, gbc);
JLabel LSOANameLabel = new JLabel("Enter LSOA Name here");
LSOANameLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 3;
getContentPane().add(LSOANameLabel, gbc);
JTextField LSOANameText = new JTextField(20);
getContentPane().add(LSOANameText, gbc);
JButton search = new JButton("Search");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(search, gbc);
search.addActionListener(this);
JButton exportnoid = new JButton("Export No Crime ID");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(exportnoid, gbc);
JButton exportdup = new JButton("Export Duplicate ID");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(exportdup, gbc);
f.add(getContentPane());
pack();
f.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
if(e.getSource()==search){
System.out.println("");
} else {
}
}
}
class GUIHandler {
public static void main(String[] args) {
GUI a = new GUI();
}
}

search variable is not an instance variable, its scope is limited to the constructor, so you cannot use it outside of it.
Declare JButton search variable after Connection con = null;.
Also note that have empty 'else' statement in actionPerformed method.

No, there is no variable search in the scope of your class GUI.
There is a local variable search in the constructor of your class GUI.
The only instance variable I see so far, is the variable con of type Connection.
You should declare search as an instance variable of GUI, just like con, if you want to use it in another method. My suggestion is, you make it private.
Alternatively you could use setActionCommand(String cmd) to set an action command name for your JButton. Then you can use getActionCommand() of your ActionEvent to retrieve the name of the action and react accordingly. But I do not like this approach, since in this case the compiler cannot help you much to detect name clashes.

class GUI extends JFrame implements ActionListener {
Connection con = null;
JButton search;
GUI() {
JPanel p = new JPanel();
JFrame f = new JFrame("Crime Data");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(600, 600);
f.setResizable(true);
f.setLocationRelativeTo(null);
GridBagConstraints gbc = new GridBagConstraints();
getContentPane().setLayout(new GridBagLayout());
gbc.insets = new Insets(5, 5, 5, 5);
JLabel LongLabel = new JLabel("Enter Longitude here");
LongLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 1;
getContentPane().add(LongLabel, gbc);
JTextField LongText = new JTextField(20);
getContentPane().add(LongText, gbc);
JLabel LatLabel = new JLabel("Enter Latitude here");
LatLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 2;
getContentPane().add(LatLabel, gbc);
JTextField LatText = new JTextField(20);
getContentPane().add(LatText, gbc);
JLabel LSOANameLabel = new JLabel("Enter LSOA Name here");
LSOANameLabel.setForeground(Color.gray);
gbc.gridx = 0;
gbc.gridy = 3;
getContentPane().add(LSOANameLabel, gbc);
JTextField LSOANameText = new JTextField(20);
getContentPane().add(LSOANameText, gbc);
search = new JButton("Search");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(search, gbc);
search.addActionListener(this);
JButton exportnoid = new JButton("Export No Crime ID");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(exportnoid, gbc);
JButton exportdup = new JButton("Export Duplicate ID");
gbc.gridx = 0;
gbc.gridy = -1;
getContentPane().add(exportdup, gbc);
f.add(getContentPane());
pack();
f.setVisible(true);
}
}

Java GUI: How do I have more than one button on a row using GridBagLayout

I'm fairly new to java and I'm having a problem trying to put more than one button on a row,
at the moment I'm adding both buttons to the panel, but I don't know how to separate their x locations, i.e. they are both being added directly on to of each other.
Do I need to create a new layout or can I find a solution using what I have at the moment?
public class Question1 {
public static void main (String[] args){
MyFrame f = new MyFrame("Simple Submit Cancel Form");
f.init();
}
}
class MyFrame extends JFrame{
MyFrame(String title){
super(title);
}
private JPanel mainPanel;
private GridBagConstraints cText = new GridBagConstraints();
private GridBagConstraints cButton = new GridBagConstraints();
private GridBagLayout gbLayout = new GridBagLayout();
void init(){
mainPanel = new JPanel();
mainPanel.setLayout(gbLayout);
mainPanel.setBorder(BorderFactory.createEmptyBorder(10,20,10,20));
this.setContentPane(mainPanel);
cText.anchor = GridBagConstraints.WEST;
cText.weightx = 0.0;
cText.gridx = 0;
cText.gridy = 0;
JTextField tf = new JTextField(20);
gbLayout.setConstraints(tf,cText);
mainPanel.add(tf);
cButton.gridwidth = 4;
cButton.weightx = 0.0;
cButton.gridx = 0;
cButton.gridy = 1;
JButton b = new JButton("Submit");
gbLayout.setConstraints(b,cButton);
mainPanel.add(b);
b = new JButton("Cancel");
gbLayout.setConstraints(b,cButton);
mainPanel.add(b);
this.pack();
this.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE) ;
this.setVisible(true);
}

Just increment the gridx value:
JButton b = new JButton("Submit");
// gbLayout.setConstraints(b,cButton);
mainPanel.add(b, cButton);
b = new JButton("Cancel");
cButton.gridx++;
// gbLayout.setConstraints(b,cButton);
mainPanel.add(b, cButton);
Also you need to use the constraints created when adding your component to the grid bag layout using container.
e.g.,
import java.awt.*;
import javax.swing.*;
public class Question1 {
public static void main(String[] args) {
MyFrame f = new MyFrame("Simple Submit Cancel Form");
f.init();
}
}
class MyFrame extends JFrame {
private static final int GAP = 2;
MyFrame(String title) {
super(title);
}
private JPanel mainPanel;
private GridBagLayout gbLayout = new GridBagLayout();
void init() {
mainPanel = new JPanel();
mainPanel.setLayout(gbLayout);
mainPanel.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
this.setContentPane(mainPanel);
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.WEST;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(GAP, GAP, GAP, GAP);
gbc.gridwidth = 2;
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.gridx = 0;
gbc.gridy = 0;
JTextField tf = new JTextField(20);
mainPanel.add(tf, gbc);
gbc.gridwidth = 1;
gbc.gridx = 0;
gbc.gridy = 1;
JButton b = new JButton("Submit");
mainPanel.add(b, gbc);
b = new JButton("Cancel");
gbc.gridx++;
mainPanel.add(b, gbc);
this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}
}

Try the following code:
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Question1 {
public static void main(String[] args) {
MyFrame f = new MyFrame("Simple Submit Cancel Form");
f.init();
}
}
class MyFrame extends JFrame {
MyFrame(String title) {
super(title);
}
private JPanel mainPanel;
private GridBagConstraints cText = new GridBagConstraints();
private GridBagConstraints cButton = new GridBagConstraints();
private GridBagLayout gbLayout = new GridBagLayout();
void init() {
mainPanel = new JPanel();
mainPanel.setLayout(gbLayout);
mainPanel.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
this.setContentPane(mainPanel);
cText.anchor = GridBagConstraints.WEST;
cText.weightx = 0.0;
cText.gridx = 0;
cText.gridy = 0;
JTextField tf = new JTextField(20);
gbLayout.setConstraints(tf, cText);
mainPanel.add(tf);
cButton.gridwidth = 4;
cButton.weightx = 0.0;
cButton.gridx = 0;
cButton.gridy = 1;
JPanel demoPanel = new JPanel();
JButton b = new JButton("Submit");
gbLayout.setConstraints(demoPanel, cButton);
demoPanel.add(b);
b = new JButton("Cancel");
// gbLayout.setConstraints(b,cButton);
demoPanel.add(b);
mainPanel.add(demoPanel);
this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}
}
I have just put the two buttons inside a JPanel and put the JPanel inside the GridBagLayout Panel !

Multiple Panels Below Each Other

Is it possible i can have a top panel for a login. Then a middle and bottom panel underneath.
I'm using gridbaglayout and i have assigned 2 panels. One panel has components linked to it for login details and the other panel has other components linked to it. However, it's not going occurring to plan.
Ive tried using Box/Borderlayout to do this, but then i'm not able to create the spacing i want.
Here is a sketch of what i want.
public class GUI extends JFrame{
private JPanel myTopPL, myTopPL2;
private JTextField myUsernameTF;
private JTextField myPasswordTF;
private JTextField myMessageTF;
private JLabel myUsernameLBL;
private JLabel myPasswordLBL;
private JLabel myItemsLBL;
private JTextArea myMainTA;
private JButton myLoginBN;
private JButton myConnectBN;
private JButton mySendBN;
private JComboBox myItemsCB;
public GUI () {
super("GUI ");
setLayout(new GridBagLayout());
myTopPL = new JPanel();
myTopPL2 = new JPanel();
myTopPL.setLayout(new GridBagLayout());
myTopPL2.setLayout(new GridBagLayout());
GridBagConstraints myTopPLGBC = new GridBagConstraints();
myTopPLGBC.weightx = 1;
myTopPLGBC.weighty = 1;
GridBagConstraints myTopPLGBC2 = new GridBagConstraints();
myTopPLGBC.weightx = 2;
myTopPLGBC.weighty = 2;
myUsernameLBL = new JLabel("Username: ");
myUsernameLBL.setFont(new Font("Arial", Font.BOLD, 13));
myTopPLGBC.gridx = 1;
myTopPLGBC.gridy = 1;
myTopPLGBC.insets = new Insets(5,5,5,5);
myTopPL.add(myUsernameLBL, myTopPLGBC);
myUsernameTF = new JTextField(10);
myTopPLGBC.gridx = 2;
myTopPLGBC.gridy = 1;
myTopPLGBC.insets = new Insets(5,5,5,5);
myTopPL.add(myUsernameTF,myTopPLGBC);
myPasswordLBL = new JLabel("Password: ");
myPasswordLBL.setFont(new Font("Arial", Font.BOLD, 13));
myTopPLGBC.gridx = 3;
myTopPLGBC.gridy = 1;
myTopPLGBC.insets = new Insets(5,5,5,5);
myTopPL.add(myPasswordLBL, myTopPLGBC);
myPasswordTF = new JTextField(10);
myTopPLGBC.gridx = 4;
myTopPLGBC.gridy = 1;
myTopPLGBC.insets = new Insets(5,5,5,5);
myTopPL.add(myPasswordTF,myTopPLGBC);
myLoginBN = new JButton("Login");
myTopPLGBC.gridx = 5;
myTopPLGBC.gridy = 1;
myTopPLGBC.insets = new Insets(5,5,5,5);
myTopPL.add(myLoginBN,myTopPLGBC);
myItemsLBL = new JLabel("Items: ");
myItemsLBL.setFont(new Font("Arial", Font.BOLD, 13));
myTopPLGBC2.gridx = 1;
myTopPLGBC2.gridy = 3;
myTopPLGBC2.insets = new Insets(5,5,5,5);
myTopPL2.add(myItemsLBL, myTopPLGBC2);
myItemsCB = new JComboBox();
myItemsCB.addItem(" Select an Item ");
myTopPLGBC2.gridx = 1;
myTopPLGBC2.gridy = 4;
myTopPLGBC2.insets = new Insets(5,5,5,5);
myTopPL2.add(myItemsCB, myTopPLGBC2);
myConnectBN = new JButton("Connect");
myTopPLGBC2.gridx = 2;
myTopPLGBC2.gridy = 4;
myTopPLGBC2.insets = new Insets (5,5,5,5);
myTopPL2.add(myConnectBN, myTopPLGBC2);
GridBagConstraints GBC = new GridBagConstraints();
GBC.anchor = GridBagConstraints.NORTHWEST;
GBC.weightx = 1;
GBC.weighty = 1;
this.add(myTopPL,GBC);
GridBagConstraints GBC2 = new GridBagConstraints();
GBC2.anchor = GridBagConstraints.NORTHWEST;
GBC2.weightx = 2;
GBC2.weighty = 2;
this.add(myTopPL2,GBC2);
}
public static void main(String[] args) {
GUI GUI = new GUI ();
GUI .setDefaultCloseOperation(RMIAuctionHouse.EXIT_ON_CLOSE);
GUI .setSize(750,500);
GUI .setVisible(true);
}
}

I'd break down the application into it's individual areas of responsibilities and focus on creating the UI elements to support it. This will allow you to focus on the needs of each section of your application, it also allows you the opportunity to change around the layout as you need
public class TestLayout15 {
public static void main(String[] args) {
new TestLayout15();
}
public TestLayout15() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new MainPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class MainPane extends JPanel {
private JTextField messageField;
private JButton sendButton;
public MainPane() {
setBorder(new EmptyBorder(4, 4, 4, 4));
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = GridBagConstraints.REMAINDER;
add(new LoginPane(), gbc);
gbc.gridy++;
add(new ConnectPane(), gbc);
gbc.gridy++;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(new JScrollPane(new JTextArea(5, 20)), gbc);
gbc.gridwidth = 1;
messageField = new JTextField(10);
sendButton = new JButton("Send");
gbc.gridy++;
gbc.weighty = 0;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(messageField, gbc);
gbc.gridx++;
gbc.weightx = 0;
add(sendButton, gbc);
}
}
public class ConnectPane extends JPanel {
private JComboBox comboBox;
private JButton connectButton;
public ConnectPane() {
comboBox = new JComboBox();
connectButton = new JButton("Connect");
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.WEST;
add(comboBox, gbc);
gbc.gridx++;
gbc.weightx = 1;
add(connectButton, gbc);
}
}
public class LoginPane extends JPanel {
private JTextField userNameField;
private JPasswordField passwordField;
private JButton loginButton;
public LoginPane() {
userNameField = new JTextField(10);
passwordField = new JPasswordField(10);
loginButton = new JButton("Login");
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.WEST;
add(new JLabel("User name:"), gbc);
gbc.gridx++;
add(userNameField, gbc);
gbc.gridx++;
add(new JLabel("Password:"), gbc);
gbc.gridx++;
add(passwordField, gbc);
gbc.gridx++;
gbc.weightx = 1;
add(loginButton, gbc);
}
}
}

To start with, replace the call to GUI.setSize(750,500) with GUI.pack(). That will size the window to fit your content. After doing that you'll see the second panel is appearing to the right of the first. This is because you did not set gridx/gridy on GBC2 so it defaults to putting myTopPL2 to the right of myTopPL1, not below it.
I rarely explicitly set the gridx/gridy when using GridBagLayout. For your first row of the display, I would use default values for all but myLoginBN where I would set gridwidth to GridBagConstraints.REMAINDER. That tells GridBagLayout that nothing else goes on this row. The next item added with a default gbc will be placed at the start of the second row.
Minor nits:
Use standard Java capitalization:
Class name are camelcase with a leading uppercase character. So, "Gui", not "GUI".
Instance names are camelcase with a leading lowercase character. So, "gbc1" not "GBC1"
Use SwingUtilities.InvokeLater to start the Gui on the EDT
SwingUtilities.invokeLater(new Runnable() {
public void run() {
GUI GUI = new GUI ();
GUI .setDefaultCloseOperation(RMIAuctionHouse.EXIT_ON_CLOSE);
GUI .setSize(750,500);
GUI .setVisible(true);
}});

Seems you are not familiar with Java layouts, so i recomend you to try null(absolute) Layout:
setLayout(null);
...
component.setBounds( x, y, width, heigh );
add(component);
Here example
package gui;
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class GUI extends JFrame{
private JTextField myUsernameTF;
private JLabel myUsernameLBL;
public GUI() {
super("GUI ");
setLayout(null);
myUsernameLBL = new JLabel("Username: ");
myUsernameLBL.setFont(new Font("Arial", Font.BOLD, 13));
myUsernameLBL.setBounds(50,30,80,20);
add(myUsernameLBL);
myUsernameTF = new JTextField(10);
myUsernameTF.setBounds(190,30,80,20);
add(myUsernameTF);
// and so on ...
}
public static void main(String[] args) {
GUI frame = new GUI();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(750,500);
frame.setVisible(true);
}
}
Good luck on thorny way to handle java swing =)

Aligning panels with GridBagLayout

I'm not exactly new to java (I've been using it for a year now) but this is my first go at swing. I'm trying to make a very simple chat client to learn both socket and swing at once. My question is "What must I do to align my panels correctly?". I've tried a lot of things (Though I don't have it in my code). Usually I work something like this out on my own, but I'm to the point I need to ask for help. Do I need to change the wieghtx, weighty? What I want the client to look like is something like this.
This is what it currently looks like.
Here is my code.
package com.client.core;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Window extends JFrame{
private int screenWidth = 800;
private int screenHeight = 600;
public Window(){
//Initial Setup
super("NAMEHERE - Chat Client Alpha v0.0.1");
setResizable(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(screenWidth,screenHeight);
GridBagConstraints c = new GridBagConstraints();
//Main Panel
JPanel window = new JPanel();
window.setLayout(new GridBagLayout());
window.setBackground(Color.black);
//Panels
JPanel display = new JPanel();
JPanel chat = new JPanel();
chat.setLayout(new GridBagLayout());
JPanel users = new JPanel();
display.setBackground(Color.blue);
c.gridx = 0;
c.gridy = 0;
c.insets= new Insets(5,5,5,5);
window.add(display, c);
chat.setBackground(Color.red);
c.gridx = 0;
c.gridy = 3;
c.gridheight = 2;
c.gridwidth = 1;
c.insets= new Insets(5,5,5,5);
window.add(chat, c);
users.setBackground(Color.green);
c.gridx = 2;
c.gridy = 0;
c.insets= new Insets(5,5,5,5);
window.add(users, c);
//Buttons
//Text fields
JTextArea text = new JTextArea("DEREADFADSFEWFASDFSADFASDF");
c.gridx = 0;
c.gridy = 0;
chat.add(text);
JTextField input = new JTextField("type here to chat", 50);
c.gridx = 0;
c.gridy = 1;
c.insets= new Insets(5,5,5,5);
chat.add(input);
add(window);
}
static class ActLis implements ActionListener{
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
}
}
}

If you wanted something like this as an output :
You can take help from this code example, though you can remove the last ButtonPanel if you don't need that :
package to.uk.gagandeepbali.swing.messenger.gui;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Color;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.JTextField;
public class ChatPanel extends JPanel
{
private JButton backButton;
private JButton exitButton;
private JButton sendButton;
private JTextPane chatPane;
private JTextPane namePane;
private JTextField chatField;
private GridBagConstraints gbc;
private final int GAP = 10;
private final int SMALLGAP = 1;
public ChatPanel()
{
gbc = new GridBagConstraints();
}
protected void createGUI()
{
setOpaque(true);
setBackground(Color.WHITE);
setLayout(new BorderLayout(5, 5));
JPanel centerPanel = new JPanel();
centerPanel.setOpaque(true);
centerPanel.setBackground(Color.WHITE);
centerPanel.setBorder(BorderFactory.createEmptyBorder(GAP, GAP, 0, GAP));
centerPanel.setLayout(new GridBagLayout());
gbc.gridx = 0;
gbc.gridy = 0;
gbc.gridwidth = 5;
gbc.weightx = 0.8;
gbc.weighty = 1.0;
gbc.fill = GridBagConstraints.BOTH;
gbc.anchor = GridBagConstraints.FIRST_LINE_START;
chatPane = new JTextPane();
JScrollPane scrollerChat = new JScrollPane();
scrollerChat.setBorder(BorderFactory.createTitledBorder("Chat"));
scrollerChat.setViewportView(chatPane);
centerPanel.add(scrollerChat, gbc);
gbc.gridx = 5;
gbc.gridwidth = 2;
gbc.weightx = 0.2;
namePane = new JTextPane();
JScrollPane scrollerName = new JScrollPane(namePane);
scrollerName.setBorder(BorderFactory.createTitledBorder("Names"));
centerPanel.add(scrollerName, gbc);
gbc.gridx = 0;
gbc.gridy = 5;
gbc.gridwidth = 5;
gbc.weightx = 0.8;
gbc.weighty = 0.1;
gbc.fill = GridBagConstraints.HORIZONTAL;
chatField = new JTextField();
chatField.setOpaque(true);
chatField.setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createTitledBorder("")
, BorderFactory.createEmptyBorder(SMALLGAP, SMALLGAP, SMALLGAP, SMALLGAP)));
centerPanel.add(chatField, gbc);
gbc.gridx = 5;
gbc.gridwidth = 2;
gbc.weightx = 0.2;
sendButton = new JButton("Send");
sendButton.setBorder(BorderFactory.createTitledBorder(""));
centerPanel.add(sendButton, gbc);
JPanel bottomPanel = new JPanel();
bottomPanel.setOpaque(true);
bottomPanel.setBackground(Color.WHITE);
bottomPanel.setBorder(
BorderFactory.createTitledBorder(""));
bottomPanel.setLayout(new BorderLayout());
JPanel buttonPanel = new JPanel();
buttonPanel.setOpaque(true);
buttonPanel.setBackground(Color.WHITE);
buttonPanel.setBorder(BorderFactory.createEmptyBorder(GAP, GAP, 0, GAP));
backButton = new JButton("Back");
exitButton = new JButton("Exit");
buttonPanel.add(backButton);
buttonPanel.add(exitButton);
bottomPanel.add(buttonPanel, BorderLayout.CENTER);
add(centerPanel, BorderLayout.CENTER);
add(bottomPanel, BorderLayout.PAGE_END);
}
public JTextPane getChatPane()
{
return chatPane;
}
public JTextPane getNamePane()
{
return namePane;
}
public JTextField getChatField()
{
return chatField;
}
public JButton getExitButton()
{
return exitButton;
}
public JButton getBackButton()
{
return backButton;
}
public JButton getSendButton()
{
return sendButton;
}
}

What you could do, and probably gives the desired result
JPanel somethingHere = ...;
JPanel chat = ...;
JPanel userList = ...;
JPanel leftPanel = new JPanel( new BorderLayout() );
leftPanel.add( somethingHere, BorderLayout.CENTER );
leftPanel.add( chat, BorderLayout.SOUTH );
JPanel total = new JPanel( new BorderLayout() );
total.add( leftPanel, BorderLayout.CENTER );
total.add( userList, BorderLayout.EAST );
Way simpler then messing with GridBagLayout

Here is what I came out with thus far. The red box is where I plan to add a simple 2D avatar interface with LWJGL.
Here is the code for it
package com.client.core;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
public class Window extends JFrame{
private int screenWidth = 800;
private int screenHeight = 600;
public Window(){
//Initial Setup
super("NAMEHERE - Chat Client Alpha v0.0.1");
setResizable(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(screenWidth,screenHeight);
//Main Panels
JPanel window = new JPanel(new BorderLayout());
JPanel center = new JPanel(new BorderLayout());
JPanel right = new JPanel(new BorderLayout());
//Panels
JPanel display = new JPanel( new BorderLayout());
display.setBackground(Color.red);
JPanel chat = new JPanel();
chat.setLayout(new BoxLayout(chat, BoxLayout.Y_AXIS));
chat.setBackground(Color.blue);
JPanel users = new JPanel(new BorderLayout());
users.setBackground(Color.green);
//TextFields
JTextArea chatBox = new JTextArea("Welcome to the chat!", 7,50);
chatBox.setEditable(false);
JTextField chatWrite = new JTextField();
JScrollPane userList = new JScrollPane();
JTextField userSearch = new JTextField(10);
userList.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
users.add(userList);
users.add(userSearch, BorderLayout.NORTH);
chat.add(chatBox);
chat.add(chatWrite);
chat.setBorder(BorderFactory.createEmptyBorder(1, 1, 1, 1));
//Menu bar
JMenuBar menu = new JMenuBar();
JMenu file = new JMenu("File");
JMenuItem exit = new JMenuItem("Exit");
JMenuItem ipconnect = new JMenuItem("Connect to IP");
file.add(ipconnect);
file.add(exit);
menu.add(file);
//Main window adding
right.add(users);
center.add(display, BorderLayout.CENTER);
center.add(chat, BorderLayout.SOUTH);
window.add(center, BorderLayout.CENTER);
window.add(right, BorderLayout.EAST);
window.add(menu, BorderLayout.NORTH);
add(window);
//Listeners
chatWrite.addKeyListener(new KeyLis());
ipconnect.addActionListener(new ActLis());
exit.addActionListener(new ActLis());
}
static class KeyLis implements KeyListener{
#Override
public void keyPressed(KeyEvent e) {
if(e.getKeyCode() == KeyEvent.VK_ENTER){
System.out.println("Message recieved.");
}
}
#Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
}
#Override
public void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub
}
}
static class ActLis implements ActionListener{
#Override
public void actionPerformed(ActionEvent e) {
if(e.getActionCommand() == "Exit"){
System.exit(0);
} else if(e.getActionCommand() == "Connect to IP"){
System.out.println("Connecting....");
JFrame frameip = new JFrame();
JPanel panelip = new JPanel();
JButton buttonip = new JButton("Hello");
frameip.add(panelip);
panelip.add(buttonip);
JDialog ippop = new JDialog(frameip, "Enter IP", false);
}
}
}
}

I had to build a similar layout using a GridBagLayout. The code below shows how I achieved it.
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GridBagLayoutTest {
public GridBagLayoutTest() {
JFrame jframe = new JFrame();
jframe.setLayout(new GridBagLayout());
jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jframe.setSize(800, 600);
jframe.setVisible(true);
// Left
JPanel leftPanel = new JPanel(new GridBagLayout());
leftPanel.setBackground(Color.YELLOW);
GridBagConstraints gridBagConstraints = new GridBagConstraints();
gridBagConstraints.fill = GridBagConstraints.BOTH;
gridBagConstraints.weightx = .7f;
gridBagConstraints.weighty = 1f;
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 0;
jframe.add(leftPanel, gridBagConstraints);
JPanel leftTopPanel = new JPanel(new FlowLayout());
leftTopPanel.setBackground(Color.RED);
GridBagConstraints gridBagConstraints0 = new GridBagConstraints();
gridBagConstraints0.fill = GridBagConstraints.BOTH;
gridBagConstraints0.weightx = 1f;
gridBagConstraints0.weighty = .7f;
gridBagConstraints0.gridx = 0;
gridBagConstraints0.gridy = 0;
leftPanel.add(leftTopPanel, gridBagConstraints0);
JPanel leftMiddlePanel = new JPanel(new FlowLayout());
leftMiddlePanel.setBackground(Color.BLACK);
gridBagConstraints0 = new GridBagConstraints();
gridBagConstraints0.fill = GridBagConstraints.BOTH;
gridBagConstraints0.weightx = 1f;
gridBagConstraints0.weighty = .2f;
gridBagConstraints0.gridx = 0;
gridBagConstraints0.gridy = 1;
leftPanel.add(leftMiddlePanel, gridBagConstraints0);
JPanel leftBottomBottomPanel = new JPanel(new FlowLayout());
leftBottomBottomPanel.setBackground(Color.PINK);
gridBagConstraints0 = new GridBagConstraints();
gridBagConstraints0.fill = GridBagConstraints.BOTH;
gridBagConstraints0.weightx = 1f;
gridBagConstraints0.weighty = .1f;
gridBagConstraints0.gridx = 0;
gridBagConstraints0.gridy = 2;
leftPanel.add(leftBottomBottomPanel, gridBagConstraints0);
// Right
JPanel rightPanel = new JPanel();
rightPanel.setBackground(Color.GREEN);
gridBagConstraints = new GridBagConstraints();
gridBagConstraints.fill = GridBagConstraints.BOTH;
gridBagConstraints.weightx = .3f;
gridBagConstraints.weighty = 1f;
gridBagConstraints.gridx = 1;
gridBagConstraints.gridy = 0;
jframe.add(rightPanel, gridBagConstraints);
}
public static void main (String args[]) {
new GridBagLayoutTest();
}