For some reason, when I run this code, my JFrame comes up as blank. I have been trying online tutorials for maybe an hour now, and I'm wondering if I'm misunderstanding something.
Here is the code:
public class Application {
public static JFrame f;
public static JButton submit;
public static JTextField unscramblee;
public static String scrambledWord, possibleWords;
public static JLabel possibleWordsDisplay;
public static JPanel UI;
public static JScrollPane scrollPane;
Application() {
f = new JFrame("test");
f.setResizable(true);
f.setLayout(null);
f.setVisible(true);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
UI = new JPanel();
scrollPane = new JScrollPane(UI);
unscramblee = new JTextField("test");
unscramblee.setBounds(240, 200, 400, 50);
submit = new JButton("Submit");
submit.setBounds(240, 350, 400, 100);
possibleWordsDisplay = new JLabel("possibleWordsDisplay - this is a display for words that are possible");
possibleWordsDisplay.setBounds(240, 0, 200, 200);
scrollPane.add(unscramblee);
scrollPane.add(submit);
scrollPane.add(possibleWordsDisplay);
f.getContentPane().add(scrollPane);
f.pack();
f.setSize(1280,720);
}
}
I hope this is enough information to help. Thanks.
(If anyone is wondering why the setSize method comes after the pack method, it's because the JFrame keeps collapsing on itself when I run it. If you also know how to fix that please tell me! I'd be very thankful.)
Setting bound manually is not a viable practice.
Instead use the appropriate Layout Managers for the desired layout.
The following is mre1 (note the comments) :
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
public class Application {
Application() {
JFrame f = new JFrame("test");
//f.setSize(1280,720); f.pack should automatically set the size
f.setResizable(true);
//f.setLayout(null); do not use null layout
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel UI = new JPanel(); // uses flowlayout by default
//UI.setBounds(0, 0, 1280, 720); do not set bounds. that the job of the layout manager
JTextField unscramblee = new JTextField("test", 10);
//unscramblee.setBounds(240, 200, 400, 50);
JButton submit = new JButton("Submit");
//submit.setBounds(240, 350, 400, 100);
JLabel possibleWordsDisplay = new JLabel("possibleWordsDisplay - this is a display for words that are possible");
//possibleWordsDisplay.setBounds(240, 0, 200, 200);
UI.add(unscramblee);
UI.add(submit);
UI.add(possibleWordsDisplay);
JScrollPane scrollPane = new JScrollPane(UI);
f.getContentPane().add(scrollPane); //uses borderlayout by default
f.pack();
f.setVisible(true); //make frame visible after construction is completed
}
public static void main(String[] args) {
new Application();
}
}
1 Always consider an mre when posting question or answers
When creating a GUI, consider following the below design to start:
private JFrame frame;
private JPanel contentPane;
public static void main(String[] args) {
GUI gui = new GUI();
gui.start();
}
private void start() {
frame = new JFrame("test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
makeContent();
frame.setSize(500, 130);
frame.setVisible(true);
}
private void makeContent() {
contentPane = (JPanel) frame.getContentPane();
makePanel();
}
private void makePanel() {
JPanel ui = new JPanel();
ui.setLayout(new BoxLayout(ui, BoxLayout.Y_AXIS));
JLabel possibleWordsDisplay = new JLabel("possibleWordsDisplay - this is a display for words that are possible");
ui.add(possibleWordsDisplay);
JTextField unscramblee = new JTextField();
JScrollPane scroll = new JScrollPane(unscramblee);
scroll.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED);
ui.add(scroll);
JButton submit = new JButton("Submit");
ui.add(submit);
contentPane.add(ui, BorderLayout.CENTER);
}
Related
I am making an UI in a minecraft plugin. Everything is working, except I have a JPanel and it doesn't fill the whole JFrame. So what I want is the JPanel fill the entire JFrame even if we re-scale the window.
I use Layout manager (FlowLayout) for the JPanel.
I tried using a Layout manager for the JFrame, well it didn't solved my problem because it didn't resize the JPanel.. I tried setting the size of the JPanel to the JFrame's size, but when it's resized it doesn't scale with it.
So, how can I do this?
My plugin creates a button for every player and when I click the button it kicks the player.
My code (I can't really post less because I don't know where I need to change something):
public static JFrame f;
public static JTextField jtf;
public static JPanel jp;
public static void creategui()
{
System.out.println("GUI created.");
f = new JFrame("Players");
jp = new JPanel();
jp.setLayout(new FlowLayout(FlowLayout.LEFT));
jp.setBackground(Color.GRAY);
jtf = new JTextField("Reason");
jtf.setPreferredSize(new Dimension(200,20));
jtf.setToolTipText("Write the reason here.");
jp.setSize(new Dimension(200,200));
f.setLayout(null);
f.setSize(500,500);
f.setVisible(true);
jp.add(jtf);f.add(jp, BorderLayout.CENTER);
for (final Player p : Bukkit.getOnlinePlayers())
{
System.out.println("Looping.");
final JButton b = new JButton();
b.setName(p.getName());
b.setText(p.getName());
b.setToolTipText("Kick " + b.getText());
b.setBackground(Color.GREEN);
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (!b.getBackground().equals(Color.RED))
{
Bukkit.getScheduler().runTask(main, new Runnable() {
public void run() {
Bukkit.getPlayer(b.getText()).kickPlayer(jtf.getText());
b.setBackground(Color.RED);
}
});
}
}
});
jp.add(b);
System.out.println("Button added.");
}
f.add(jp, BorderLayout.CENTER);
}
The question should include an mcve reproducing the problem so we can test it.
It could look like this :
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.util.Arrays;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Mcve {
private static List<String> players = Arrays.asList(new String[]{"Player A", "Player B"});
public static void main(String[] args) {
creategui();
}
public static void creategui()
{
JPanel jp = new JPanel();
jp.setBackground(Color.GRAY);
JTextField jtf = new JTextField("Reason");
jtf.setPreferredSize(new Dimension(200,20));
jtf.setToolTipText("Write the reason here.");
jp.setSize(new Dimension(200,200));
jp.add(jtf);
for (final String p : players)
{
final JButton b = new JButton();
b.setText(p);
b.setBackground(Color.GREEN);
b.addActionListener(e -> {
if (!b.getBackground().equals(Color.RED))
{
b.setBackground(Color.RED);
}
});
jp.add(b);
}
JFrame f = new JFrame("Players");
f.setLayout(null);
f.setSize(500,500);
f.add(jp, BorderLayout.CENTER);
f.setVisible(true);
}
}
To make the JPanel fill the entire frame simply remove this line :
f.setLayout(null);
and let the default BorderLayout manager do its work.
Here is a modified version with some additional comments:
public class Mcve {
private static List<String> players = Arrays.asList(new String[]{"Player A", "Player B"});
public static void main(String[] args) {
creategui();
}
public static void creategui()
{
JPanel jp = new JPanel();
jp.setBackground(Color.GRAY);
JTextField jtf = new JTextField("Reason");
jtf.setPreferredSize(new Dimension(200,20));
jtf.setToolTipText("Write the reason here.");
jp.setPreferredSize(new Dimension(250,200)); // set preferred size rather than size
jp.add(jtf);
for (final String p : players)
{
final JButton b = new JButton();
b.setText(p);
b.setBackground(Color.GREEN);
b.addActionListener(e -> {
if (!b.getBackground().equals(Color.RED))
{
b.setBackground(Color.RED);
}
});
jp.add(b);
}
JFrame f = new JFrame("Players");
//f.setLayout(null); null layouts are bad practice
//f.setSize(500,500); let layout managers set the sizes
f.add(jp, BorderLayout.CENTER);
f.pack();
f.setVisible(true);
}
}
A 1x1 grid layout does the job quite nicely.
window = new JFrame();
panel = new JPanel();
window.setLayout(new java.awt.GridLayout(1, 1));
window.add(panel);
Either set the layout manager for jp (the JPanel in the code you posted) to BorderLayout and add jtf (the JTextField in the code you posted) to the CENTER of jp, as in:
f = new JFrame();
jp = new JPanel(new BorderLayout());
jtf = new JTextField(30); // number of columns
jp.add(jtf, BorderLayout.CENTER);
f.add(jp, BorderLayout.CENTER);
or dispense with jp and add jtf directly to f (the JFrame in the code you posted), as in:
f = new JFrame();
jtf = new JTextField(30);
f.add(jtf, BorderLayout.CENTER);
The key is that the CENTER component of BorderLayout expands to fill the available space.
So I fixed it somehow, this is the code:
public static void creategui()
{
System.out.println("GUI created.");
f = new JFrame("Players");
jp = new JPanel();
jp.setBackground(Color.GRAY);
jp.setSize(200,200);
jtf = new JTextField(30);
jtf.setToolTipText("Write the reason here.");
jp.add(jtf);
for (final Player p : Bukkit.getOnlinePlayers())
{
System.out.println("Looping.");
final JButton b = new JButton();
b.setName(p.getName());
b.setText(p.getName());
b.setToolTipText("Kick " + b.getText());
b.setBackground(Color.GREEN);
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (!b.getBackground().equals(Color.RED))
{
Bukkit.getScheduler().runTask(main, new Runnable() {
public void run() {
getplr(b.getText()).kickPlayer(jtf.getText());
b.setBackground(Color.RED);
}
});
}
}
});
jp.add(b);
System.out.println("Button added.");
}
f.setLayout(new BorderLayout());
f.add(jp, BorderLayout.CENTER);
f.setSize(500,500);
f.pack();
f.setVisible(true);
}
I have problem with displaying components on my JFrame. I'm closing my current window and opening new one and want to display jLabel on it but nothing is happening. Code is below :
Frame[] nF = DBChooser.getFrames();
nF[0].setVisible(false);
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel ("Processing...");
textLabel.setLayout(null);
pan.setLayout(null);
windoow.setLayout(null);
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
I appreciate any help
Why you need so many setLayout(null); ? I remove them and it worked
public class DBChooser extends Frame {
public static void main(String args[]) {
Frame[] nF = DBChooser.getFrames();
// nF[0].setVisible(false);
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel("Processing...");
// textLabel.setLayout(null);
// pan.setLayout(null);
// windoow.setLayout(null);
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
}
}
It is because you set a null layout to window and panel without specifying any width, lenght or position, either use some LayoutManager or set these properties (eg. bounds). A null LayoutManager means that you need to set everything yourself, because there is nothing (no LayoutManager) that would place your elements automatically. This example uses a BorderLayout, which creates a nice effect:
the code:
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Test {
public static void main(String[] args) {
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel("Processing...");
textLabel.setLayout(null);
pan.setLayout(new BorderLayout());
windoow.setLayout(new BorderLayout());
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
}
}
I am new to working with GUI's in Java and I am having a problem moving my text and buttons around. No matter what coordinates I give my button or any of the other JLabel it doesn't move, I was wondering how I could fix it this in such a way that I can place my components where ever I want on the JPanel
public class IntroPage extends JFrame {
public static void main(String[] args) {
IntroPage main = new IntroPage();
main.setVisible(true);
}
private JPanel contentPane;
public IntroPage (){
//make sure the program exits when the frame closes
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("Welcome");
contentPane = new JPanel();
setSize(400,700);
//This will center the JFrame in the middle of the screen
setLocationRelativeTo(null);
//Welcome Page stuff :D
JLabel ApplauseLabel = new JLabel("Welcome to U.X.Dot.X");
ApplauseLabel.setFont(new Font("Gill Sans MT", Font.PLAIN, 30));
ApplauseLabel.setLocation(100, 50);
contentPane.add(ApplauseLabel);
JLabel slogan = new JLabel("Register below");
slogan.setFont(new Font("Gill Sans MT", Font.PLAIN, 15));
slogan.setLocation(100, 400);
contentPane.add(slogan);
//FacebookSignUp.
JButton FBbutton = new JButton("Login With FaceBook");
FBbutton.setBackground(Color.BLUE);
FBbutton.setSize(50,50);
FBbutton.setLocation(20, 40);
FBbutton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//Add JPanel to go to FB API. Much later
}
});
contentPane.add(FBbutton);
add(contentPane);
//make sure the JFrame is visible
setVisible(true);
}
}
You're ignoring the layout managers of your contentPane JPanel. Understand that it uses FlowLayout by default, and will ignore your setLocation and setBounds statements. Ror the JPanel to accept absolute positioning, you would have to give it a null layout via contentPane.setLayout(null).
Having said that, I do not advise you to do this! While null layouts, setLocation(...) and setBounds(...) might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
For example the following GUI
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import javax.swing.*;
public class IntroPage2 extends JPanel {
public static final String TITLE = "Welcome to U.X.Dot.X";
private JLabel welcomeLabel = new JLabel(TITLE, SwingConstants.CENTER);
private JButton fbButton = new JButton("Login With Facebook");
public IntroPage2() {
fbButton.setBackground(Color.BLUE);
fbButton.setForeground(Color.CYAN);
welcomeLabel.setFont(new Font(Font.SANS_SERIF, Font.PLAIN, 30));
int wlGap = 20;
welcomeLabel.setBorder(BorderFactory.createEmptyBorder(wlGap, wlGap, wlGap, wlGap));
JLabel registerBelowLabel = new JLabel("Register Below");
registerBelowLabel.setFont(new Font(Font.SANS_SERIF, Font.PLAIN, 15));
JPanel centralPanel = new JPanel(new GridBagLayout());
centralPanel.setPreferredSize(new Dimension(300, 600));
centralPanel.add(registerBelowLabel);
JPanel topPanel = new JPanel(new BorderLayout());
topPanel.add(fbButton, BorderLayout.LINE_START);
topPanel.add(welcomeLabel, BorderLayout.CENTER);
setLayout(new BorderLayout());
int ebGap = 8;
setBorder(BorderFactory.createEmptyBorder(ebGap, ebGap, ebGap, ebGap));
add(topPanel, BorderLayout.PAGE_START);
add(centralPanel, BorderLayout.CENTER);
}
private static void createAndShowGui() {
IntroPage2 mainPanel = new IntroPage2();
JFrame frame = new JFrame("Welcome");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
would create something like:
I've been trying to setup a JFrame with text but I'm having trouble. I can create the JFrame, but I can't get a background color or text to work with it.
import java.awt.Color;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
class FundManager {
JFrame window;
JPanel panel;
JLabel text;
public void createWindow()
{
//Create the window
window = new JFrame();
window.setVisible(true);
window.setSize(960, 540);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setLocationRelativeTo(null);
//Create the panel
panel = new JPanel();
panel.setBackground(Color.RED);
//Create the label
text = new JLabel("test");
}
public static void main(String args[]) {
FundManager.createWindow();
}
}
My createWindow() method is not running and I get the error:
cannot make a static reference to to the non-static method.
However, when I make it static the whole program breaks.
The issue here is that you need an instance of FundManager before you can call the method createWindow(). Try the code below instead.
new FundManager().createWindow();
First of all, you cannot make a call to FundManager.createWindow(), because createWindow() is not a static method. You need an instance of FundManager.
Furthermore, you are not adding the panel nor the text field to the frame. You are only declaring them. This is a quick example of how you could locate the elements inside the frame:
JFrame window;
JPanel panel;
JLabel text;
public void createWindow() {
// Create the window
window = new JFrame();
window.setVisible(true);
window.setSize(960, 540);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setLocationRelativeTo(null);
// Create the panel
panel = new JPanel();
panel.setPreferredSize(new Dimension(500, 500));
panel.setBackground(Color.RED);
// Create the label
text = new JLabel("test");
text.setPreferredSize(new Dimension(200, 30));
text.setLocation(100, 100);
panel.add(text);
window.getContentPane().add(panel);
window.pack();
}
And run this with:
new FundManager().createWindow();
import javax.swing.*;
import java.awt.*;
class MainGui{
JFrame frame = new JFrame();
JPanel mainPanel = new JPanel();
JButton newBut = new JButton("New Game");
JButton continueBut = new JButton("Continue");
JButton exitBut = new JButton("Exit");
JLabel backImage = new JLabel(new ImageIcon("C:\\Users\\BSK\\Desktop\\game5.jpg"));
public MainGui(){
frame.setSize(600,800);
frame.setVisible(true);
frame.setResizable(false);
setButtonSize();
frame.setLayout(new BorderLayout());
frame.setContentPane(backImage);
frame.getContentPane().setLayout(new BoxLayout(frame.getContentPane(),BoxLayout.Y_AXIS));
insertBlankArea(frame);
frame.getContentPane().add(newBut);
insertBlankArea(frame);
frame.getContentPane().add(continueBut);
insertBlankArea(frame);
frame.getContentPane().add(exitBut);
frame.setSize(799,800);
}
public void insertBlankArea(JFrame frame){
frame.getContentPane().add(Box.createRigidArea(new Dimension(280,155)));
}
public void setButtonSize(){
Dimension dim = new Dimension(100,100);//here is the problem,i am not getting the desired dimension and the size of buttons remains the default.
newBut.setPreferredSize(dim);
continueBut.setPreferredSize(dim);
exitBut.setPreferredSize(dim);
}
public static void main(String[] args) {
MainGui mainGui = new MainGui();
}
}
So iam not getting the defined size for the buttons but when i set frame.setResizable(false); then when i stretch the screen the button's height increases but its width still remains the same.
So please tell me what is going wrong?
You should take a look at A Visual Guide to Layout Managers and choose the most appropriate one for your situation. You should also avoid explicitly setting sizes (ie: setSize, setMinimumSize, setMaximumSize, and setPreferredSize) because those methods are the responsibility of the layout manager. You may also be interested in reading this question on whether or not the use of the different set size methods should be avoided or not.
Finally, you should not be calling your MainGUI class outside of the Event Dispatch Thread (EDT). Most Swing GUI-related methods are not thread safe and therefore require being executed in the EDT. Below is a corrected version of your main method:
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
MainGui mainGui = new MainGui();
}
});
}
Just reading your short descrption, I have no idea what your problem is. But based solely on the question title
"How to give a preffered size to the JButton?"
Don't. Let the the layout manager handle this for you. If you want a bigger button, you can use JButton.setMargins(Insets) and/or JButton.setFont(Font) where you specify a bigger font.
If you want you button stretched or not to stretch, You need to select an appropriate layout manager, that will or won't respect the buttons preferred size. For instance, BorderLayout and GridLayout won't respect preferred sizes and will stretch the button the fit, and FlowLayout, BoxLayout, and GridBagLayout will respect the preferred size. As you can see here
See example with GridBagLayout
import javax.swing.*;
import java.awt.*;
class MainGui {
JFrame frame = new JFrame();
JPanel mainPanel = new JPanel();
JButton newBut = new JButton("New Game");
JButton continueBut = new JButton("Continue");
JButton exitBut = new JButton("Exit");
JLabel backImage = new JLabel(new ImageIcon(
getClass().getResource("images.jpg")));
public MainGui() {
backImage.setLayout(new BorderLayout());
frame.setContentPane(backImage);
JPanel mainPanel = new JPanel(new GridBagLayout());
mainPanel.setOpaque(false);
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridy = 0;
gbc.weightx = 1.0;
gbc.weighty = 1.0;
mainPanel.add(newBut, gbc);
gbc.gridy = 1;
mainPanel.add(continueBut, gbc);
gbc.gridy = 2;
mainPanel.add(exitBut, gbc);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(mainPanel);
frame.setSize(250, 275);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
MainGui mainGui = new MainGui();
}
});
}
}
And here's with nesting panels which will give the same result
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
class MainGui {
JFrame frame = new JFrame();
JPanel mainPanel = new JPanel();
JButton newBut = new JButton("New Game");
JButton continueBut = new JButton("Continue");
JButton exitBut = new JButton("Exit");
JLabel backImage = new JLabel(new ImageIcon(
getClass().getResource("images.jpg")));
public MainGui() {
backImage.setLayout(new GridLayout(3,1));
frame.setContentPane(backImage);
JPanel p1= new JPanel(new GridBagLayout());
p1.setOpaque(false);
p1.add(newBut);
JPanel p2 = new JPanel(new GridBagLayout());
p2.setOpaque(false);
p2.add(continueBut);
JPanel p3 = new JPanel(new GridBagLayout());
p3.setOpaque(false);
p3.add(exitBut);
frame.add(p1);
frame.add(p2);
frame.add(p3);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(250, 275);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
MainGui mainGui = new MainGui();
}
});
}
}