I'm having trouble getting my GUI to contain any of my JButtons or JTextField. I have two classes One "SnowballFight" class that contains my main method and frame constructor. Then I also have "GameBoard" which sets up my GUI. My problem is that my GUI appears, but appears empty.
"SnowballFight" class:
package snowballfight;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class SnowballFight extends JFrame implements ActionListener{
public SnowballFight(){
setLayout(new BorderLayout(1,2));
}
public static void main(String[] args) {
SnowballFight frame = new SnowballFight();
GameBoard game = new GameBoard(frame);
}
public void actionPerformed(ActionEvent event) {
}
}
"GameBoard" class:
package snowballfight;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class GameBoard extends JFrame implements ActionListener{
private JButton[][] game = new JButton[10][10];
private JTextField display = new JTextField("Welcome to the SnowBall fight!");
private Opponent[] opponents = new Opponent[4];
public GameBoard(SnowballFight frame){
JPanel panel = new JPanel();
panel.setLayout(new GridLayout( 10, 10));
for (int row = 0; row < game.length; row++) {
for (int col = 0; col < game[row].length; col++) {
game[row][col] = new JButton();
game[row][col].setBackground(Color.gray);
game[row][col].addActionListener(this);
panel.add(game[row][col]);
}
}
add(display, BorderLayout.NORTH);
add(panel, BorderLayout.SOUTH);
frame.setTitle("Snowball Fight");
frame.setSize(200, 150);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public boolean isGameOver(){
for (int opponent = 0; opponent < opponents.length; opponent++) {
if(opponents[opponent].isSoaked() == false ){
return false;
}
}
return true;
}
public void actionPerformed(ActionEvent event) {
}
}
Not sure why there are two frames, but I think you're adding display and panel to the wrong frame.
Try changing:
add(display, BorderLayout.NORTH);
add(panel, BorderLayout.SOUTH);
to:
frame.add(display, BorderLayout.NORTH);
frame.add(panel, BorderLayout.SOUTH);
You never make the GameBoard JFrame visible
game.setVisible(true);
Some notes:
The frame SnowballFight has no apparent function
It's not necessary to extend JFrame since no functionality is being added
Read The Use of Multiple JFrames, Good/Bad Practice?
Related
I tried to create a JFrame and put 5 JPanels on it.
The problem is, that the top panel appears twice.
This is the Frame class:
package Chess;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import Chess.NorthPanel;
public class Frame {
public static void main(String[] args) {
drawpanels();
}
public static void drawpanels() {
JFrame board=new JFrame("Board");
board.setLayout(new BorderLayout());
board.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
board.setVisible(true);
board.setSize(1000, 1000);
board.getContentPane().setBackground(new Color(224,224,224));
NorthPanel p1=new NorthPanel();
SouthPanel p2=new SouthPanel();
CenterPanel p3=new CenterPanel();
JPanel p4=new JPanel();
JPanel p5=new JPanel();
p4.setBackground(Color.green);
p5.setBackground(Color.red);
board.add(p1, BorderLayout.NORTH);
board.add(p2, BorderLayout.SOUTH);
board.add(p3, BorderLayout.CENTER);
board.add(p4, BorderLayout.EAST);
board.add(p5, BorderLayout.WEST);
board.validate();
}
}
And this is the NorthPanel class:
package Chess;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class NorthPanel extends JPanel{
private static final long serialVersionUID = 1L;
public NorthPanel() {
this.setBackground(new Color(128,128,128));
JLabel label=new JLabel();
label.setIcon(new ImageIcon("images/rlt.png"));
this.add(label);
}
}
(There are two other classes for SouthPanel and CenterPanel.)
And the result:
Why are there two rooks?
What other problems are there with this code?
*edited so it might be helpful to others:
I was struggling with why an ImageIcon was being padded in a JPanel, but not in a JToolBar even though they were added in the same way, using the same file (see the folder icon):
Cutting down the code to an sscce has shown that VGR's answer below is right - it's has to be how each component deals with JButtons, rather than the layout.
This code should run, but you'll have to have "images/open.png" in the source folder.
import java.awt.Color;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.URL;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JToolBar;
import javax.swing.border.Border;
class CandidatePanel extends JPanel{
private JPanel panel = new JPanel();
private JToolBar tb = new JToolBar();
private JButton tbButton = new JButton();
private JButton cvButton = new JButton();
public static void main(String[] args){
JFrame frame = new JFrame();
frame.add(new CandidatePanel());
frame.pack();
frame.setVisible(true);
}
public CandidatePanel(){
setLayout(new GridBagLayout());
tbButton.setIcon(new PanelHelper().createIcon("images/open.png", ""));
tb.add(tbButton);
cvButton.setIcon(new PanelHelper().createIcon("images/open.png", ""));
cvButton.setFocusPainted(false);
cvButton.setContentAreaFilled(false);
cvButton.setBorderPainted(true);
addComponents();
add(tb);
add(panel);
}
private void addComponents(){
panel.setLayout(new GridBagLayout());
int row =0;
//new row
JPanel cvButtonPanel = (JPanel)PanelHelper.addTestBorder(new JPanel(),Color.BLUE);
cvButtonPanel.add(cvButton);
cvButtonPanel.add(PanelHelper.addTestBorder(new JPanel(), Color.RED));
panel.add(tb, new GBC(1,row));
panel.add(cvButtonPanel, new GBC(1,++row));
}
}
class PanelHelper{
public static JComponent addTestBorder(JComponent comp, Color color){
Border border = BorderFactory.createLineBorder(color);
comp.setBorder(border);
return comp;
}
public ImageIcon createIcon(String path, String btnName){
URL url = getClass().getResource(path);
if(url == null)
System.err.println("\nThe "+btnName+" Icon Path Cannot Be Found: "+path);
return new ImageIcon(url);
}
}
it was just as simple as setting the button margin, as mentioned in the comments below.
button.setMargin(new Insets(0,0,0,0))
I'm using a tabbed pane and can't get the tab to show the GUI that I want. I plan to have different Panel objects for each different tab so that I can setup their layouts with more versatility. Right now I don't have any listeners or functions, and am strictly trying to get the components to show up.
Edit: Code is now in the question, not a link.
Here is the code for the UI for the "General":
import javax.swing.JTabbedPane;
import javax.swing.JTable;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JComponent;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
public class GeneralGUI extends JPanel{
public GeneralGUI() {
JPanel topPanel = new JPanel();
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JLabel subjectNum = new JLabel("Subject Street #:");
JLabel subjectStreet = new JLabel("Subject Street Name:");
JTable compTable = new JTable();
JTable subjectTable = new JTable();
JButton getRPT = new JButton("Get RPT file");
JButton getOrder = new JButton("Get Order/Contract");
JButton subjectDocs = new JButton("Get Subject Docs");
JButton compDocs = new JButton("Get Comp Docs");
panel1.add(subjectNum);
panel1.add(subjectStreet);
panel1.add(compTable);
panel2.add(getRPT);
panel2.add(getOrder);
panel2.add(subjectDocs);
panel2.add(compDocs);
panel2.add(subjectTable);
topPanel.add(panel1);
topPanel.add(panel2);
topPanel.setVisible(true);
}
}
Here is the code for the tabbed pane code:
import javax.swing.JTabbedPane;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JComponent;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
public class AppraisalTabs extends JPanel {
public AppraisalTabs() {
super(new GridLayout(1, 1));
JTabbedPane tabbedPane = new JTabbedPane();
GeneralGUI genGUI = new GeneralGUI();
// JComponent panel1 = makeTextPanel("General");
tabbedPane.addTab("General", genGUI);
tabbedPane.setMnemonicAt(0, KeyEvent.VK_1);
JComponent panel2 = makeTextPanel("Docs");
tabbedPane.addTab("Docs", panel2);
tabbedPane.setMnemonicAt(1, KeyEvent.VK_2);
JComponent panel3 = makeTextPanel("Subject");
tabbedPane.addTab("Subject", panel3);
tabbedPane.setMnemonicAt(2, KeyEvent.VK_3);
JComponent panel4 = makeTextPanel("Comps");
panel4.setPreferredSize(new Dimension(410, 300));
tabbedPane.addTab("Comps", panel4);
tabbedPane.setMnemonicAt(3, KeyEvent.VK_4);
JComponent panel5 = makeTextPanel("Report");
panel4.setPreferredSize(new Dimension(800, 800));
tabbedPane.addTab("Report", panel5);
tabbedPane.setMnemonicAt(4, KeyEvent.VK_5);
//Add the tabbed pane to this panel.
add(tabbedPane);
//The following line enables to use scrolling tabs.
tabbedPane.setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
}
protected JComponent makeTextPanel(String text) {
JPanel panel = new JPanel(false);
JLabel filler = new JLabel(text);
filler.setHorizontalAlignment(JLabel.CENTER);
panel.setLayout(new GridLayout(1, 1));
panel.add(filler);
return panel;
}
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("Appraisal Helper");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Add content to the window.
frame.add(new AppraisalTabs(), BorderLayout.CENTER);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event dispatch thread:
//creating and showing this application's GUI.
SwingUtilities.invokeLater(new Runnable() {
public void run() {
//Turn off metal's use of bold fonts
UIManager.put("swing.boldMetal", Boolean.FALSE);
createAndShowGUI();
}
});
}
}
My problem is that once I run the code the tabbed pane shows up, as well as the correctly-titled tabs, but the "General" tab isn't showing anything at all. I tried to setup the buttons and everything in it but it's still blank.
Any ideas?
The JavaSwing application shows no errors in netbeans. When I try to run it, it takes forever and nothing is happening(JDK 8 + Netbeans 8.1). The same problem in eclipse. A simple hello world program works. The program is divided in 4 classes. Sorry for the long code.
package test2;
import javax.swing.JFrame;
import static javax.swing.JFrame.EXIT_ON_CLOSE;
public class MainWindow extends JFrame {
private Navigator navigator = new Navigator(this);
private Field spielfeld = new Field();
public MainWindow() {
super("GameTest");
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.add(spielfeld);
this.setResizable(false);
this.pack();
}
public static void main(String[] args) {
new MainWindow();
}
}
package test2;
import javax.swing.JPanel;
import javax.swing.JLabel;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
public class Field extends JPanel {
private static int x = 10;
private static int y = 10;
private JLabel[][] fields = new JLabel[10][10];
public Field() {
Dimension dim = new Dimension();
dim.setSize(50, 50);
this.setLayout(new GridLayout(x, y));
for(int i = 0; i < y; i++){
for(int j = 0; j < x; j++){
fields[i][j] = new JLabel();
fields[i][j].setPreferredSize(dim);
fields[i][j].setOpaque(true);
if((i+j)%2 == 0){
fields[i][j].setBackground(Color.BLACK);
}
else {
fields[i][j].setBackground(Color.WHITE);
}
this.add(fields[i][j]);
}
}
}
}
package test2;
import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JWindow;
public class Navigator extends JWindow {
public Navigator(JFrame parent) {
super(parent);
JPanel frame = new JPanel();
frame.setLayout(new BorderLayout());
frame.setBorder(BorderFactory.createLineBorder(Color.RED));
frame.add(new Keypad(), BorderLayout.NORTH);
this.getContentPane().add(frame);
this.updateLocation();
this.pack();
}
public void updateLocation()
{
this.setLocation((int)this.getParent().getLocation().getX() + this.getParent().getWidth() + 550,
(int)this.getParent().getLocation().getY());
}
public MainWindow getMainWindow()
{
return (MainWindow)this.getParent();
}
}
package test2;
import java.awt.ComponentOrientation;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
public class Keypad extends JPanel {
public Keypad() {
Dimension dim = new Dimension(60, 30);
this.setLayout(new GridLayout(3, 3));
this.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
for(int i = 9; 0 < i; i--) {
JButton button = new JButton(String.valueOf(i));
button.setPreferredSize(dim);
button.setVisible(true);
if(i != 5) {
this.add(button);
this.add(button);
}
}
this.setVisible(true);
}
}
You are missing setVisible(true) inside your MainWindow constructor.
The code will "run forever" with or without this line. The only difference is that the window will be shown.
I am trying to create a Java GUI application that contains a label and button. When the button is clicked the background color of the first panel is changed. I've got the label and button but getting errors whenever I click the button. Also, I wanted the first panel to originally have a yellow background then switch to whatever color. Here's my code:
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.FlowLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JLabel;
public class ChangeDemo extends JFrame implements ActionListener
{
public static final int WIDTH = 300;
public static final int HEIGHT= 200;
private JPanel biggerPanel;
public static void main(String[] args)
{
ChangeDemo gui = new ChangeDemo();
gui.setVisible(true);
}
public ChangeDemo()
{
super ("ChangeBackgroundDemo");
setSize(WIDTH,HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new GridLayout(2,3));
JPanel biggerPanel = new JPanel();
biggerPanel.setLayout(new BorderLayout());
biggerPanel.setBackground(Color.YELLOW);
JLabel namePanel = new JLabel("Click the button to change the background color");
biggerPanel.add(namePanel, BorderLayout.NORTH);
add(namePanel);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.LIGHT_GRAY);
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(this);
buttonPanel.add(changeButton);
add(buttonPanel);
}
public void actionPerformed(ActionEvent e)
{
String buttonString = e.getActionCommand();
if(buttonString.equals("Change Color"))
biggerPanel.setBackground(Color.RED);
else
System.out.println("Unexpected Error!");
}
}
I made a few changes to your code.
First, you must start a Swing application with a call to SwingUtilities.invokeLater.
public static void main(String[] args) {
SwingUtilities.invokeLater(new ChangeDemo());
}
Second, you use Swing components. You only extend a Swing component when you want to override a method of the Swing component.
Third, I made a action listener specifically for your JButton. That way, you don't have to check for a particular JButton string. You can create as many action listeners as you need for your GUI.
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
isYellow = !isYellow;
if (isYellow) buttonPanel.setBackground(Color.YELLOW);
else buttonPanel.setBackground(Color.RED);
}
});
Finally, I changed the background color of the JButton panel.
Here's the entire ChangeDemo class.
package com.ggl.testing;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class ChangeDemo implements Runnable {
private boolean isYellow;
private JFrame frame;
public static void main(String[] args) {
SwingUtilities.invokeLater(new ChangeDemo());
}
#Override
public void run() {
frame = new JFrame("Change Background Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.PAGE_AXIS));
JPanel namePanel = new JPanel();
JLabel nameLabel = new JLabel(
"Click the button to change the background color");
nameLabel.setAlignmentX(JLabel.CENTER_ALIGNMENT);
namePanel.add(nameLabel);
mainPanel.add(namePanel);
final JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.YELLOW);
isYellow = true;
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
isYellow = !isYellow;
if (isYellow) buttonPanel.setBackground(Color.YELLOW);
else buttonPanel.setBackground(Color.RED);
}
});
buttonPanel.add(changeButton);
mainPanel.add(buttonPanel);
frame.add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
}
Here is working demo based on amendments to your code, haven't had time to tidy it up but hopefully you'll get the gist of it. Problem was you hand't added Panels to the borders (north, south etc.) in order to color them. Hopefully this helps.
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.FlowLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JLabel;
public class ChangeDemo extends JFrame implements ActionListener
{
public static final int WIDTH = 300;
public static final int HEIGHT= 200;
private JPanel biggerPanel = new JPanel();
private JPanel namePanel = new JPanel();
public static void main(String[] args)
{
ChangeDemo gui = new ChangeDemo();
gui.setVisible(true);
}
public ChangeDemo()
{
super ("ChangeBackgroundDemo");
setSize(WIDTH,HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new GridLayout(2,3));
//JPanel biggerPanel = new JPanel();
this.biggerPanel.setLayout(new BorderLayout());
this.biggerPanel.setBackground(Color.YELLOW);
JLabel nameLabel = new JLabel("Click the button to change the background color");
namePanel.add(nameLabel);
namePanel.setBackground(Color.YELLOW);
//this.biggerPanel.add(namePanel, BorderLayout.NORTH);
add(namePanel);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.setBackground(Color.LIGHT_GRAY);
JButton changeButton = new JButton("Change Color");
changeButton.addActionListener(this);
changeButton.setActionCommand("Change Color");
buttonPanel.add(changeButton);
add(buttonPanel);
}
public void actionPerformed(ActionEvent e)
{
String buttonString = e.getActionCommand();
if(buttonString.equals("Change Color"))
this.namePanel.setBackground(Color.RED);
else
System.out.println("Unexpected Error!");
}
}