I am trying to add a simple JButton to a JPanel in my program. The problem is when I run the problem, I do not see any button at all.
This is my code:
import java.awt.CardLayout;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class GuiStopwatch {
public GuiStopwatch() {
JPanel panel = new JPanel();
JButton Startbtn = new JButton("START");
panel.add(Startbtn);
}
public static void main(String[] args) {
JFrame frame = new JFrame("Stopwatch");
frame.setSize(600, 600);
frame.setLayout(new FlowLayout());
frame.setVisible(true);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
}
}
May I know what did I do wrong and how do I fix this?
You are not adding the panel to the frame at any point.
EDIT
Here is the code you would need if you wanted it in a separate method:
import javax.swing.*;
import java.awt.*;
public class GuiStopwatch {
private static void stopwatch(JFrame frame) {
JPanel panel = new JPanel();
JButton Startbtn = new JButton("START");
panel.add(Startbtn);
frame.add(panel);
}
public static void main(String[] args) {
JFrame frame = new JFrame("Stopwatch");
stopwatch(frame);
frame.setSize(600, 600);
frame.setLayout(new FlowLayout());
frame.setVisible(true);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
}
}
You could swap things, create everything you need for your frame on the constructor, what makes the code more organized and also you can use it in other Classes, putting on main method will limit what you can do and makes the code not organized
See here an example:
public GuiStopwatch() {
setTitle("Stopwatch");
setSize(600, 600);
// Create JButton and JPanel
JButton button = new JButton("START");
JPanel panel = new JPanel();
panel.add(button);
this.getContentPane().add(panel);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public static void main(String[] args) {
GuiStopwatch guistopwatch = new GuiStopwatch();
}
Related
I am making a program that has multiple sub-programs but when I am trying to open a new frame, it doesn't do anything.
The program that calls the frame:
import javax.swing.*;
import java.awt.*;
public class Main {
public static void main(String[] args) {
JFrame frame = new JFrame("Options");
JButton notepad = new JButton("Notepad");
JButton todo = new JButton("To-Do List");
NoteListe noteListener = new NoteListe();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500,500);
frame.setLayout(new GridLayout(1,2));
frame.add(notepad);
frame.add(todo);
notepad.addActionListener(noteListener);
}
}
The action listener for the notepad button:
import java.awt.event.*;
public class NoteListe implements ActionListener{
public void actionPerformed(ActionEvent e){
new MainNote();
}
}
The notepad:
import javax.swing.*;
import java.awt.*;
public class MainNote {
public static void main(String[] args) {
JFrame frame = new JFrame("Text Editor");
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500,500);
frame.setLayout(new GridLayout(2,1));
}
}
I really think you need to take a closer look at:
Providing Constructors for Your Classes
Defining Methods
Passing Information to a Method or a Constructor
These are really fundamental concepts and you should have firm grasp of them before you venture into the wild and unforgiving world of GUI development.
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.border.EmptyBorder;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new MenuPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class MenuPane extends JPanel {
public MenuPane() {
setLayout(new GridBagLayout());
setBorder(new EmptyBorder(32, 32, 32, 32));
JButton notepad = new JButton("Notepad");
JButton todo = new JButton("To-Do List");
GridBagConstraints gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.BOTH;
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.insets = new Insets(8, 8, 8, 8);
add(notepad, gbc);
add(todo, gbc);
notepad.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
MainNote note = MainNote.show(MenuPane.this);
note.setText("This is where your text goes");
}
});
}
}
public static class MainNote extends JPanel {
private JTextArea ta;
public MainNote() {
setLayout(new BorderLayout());
ta = new JTextArea(20, 40);
add(new JScrollPane(ta));
}
public void setText(String text) {
ta.setText(text);
}
public String getText() {
return ta.getText();
}
public static MainNote show(Component parent) {
MainNote mainNote = new MainNote();
JFrame frame = new JFrame("Text Editor");
frame.add(mainNote);
frame.pack();
frame.setLocationRelativeTo(parent);
frame.setVisible(true);
return mainNote;
}
}
}
Note: I've used a static method (show) to simplify the construction of another window. This is simply a delegation workflow, as I'm delegating the responsibility for creating the window to the method, but I'm still getting back an instance of the MainNote.
Because MainNote is simply a JPanel, it can be added to what ever container I want. Because I've "encapsulated" the functionality into the class itself, it makes it much easier to manage.
I'm new to coding and I am facing this problem where it doesn't show the JButton and JLabel that i added in the GUI. What have i done wrong and how do i fix it?
import java.awt.ComponentOrientation;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;
public class MainMenu {
public static void main (String []args) {
JFrame frame = new JFrame ("Main Menu");
frame.setSize(480,720);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(3,2,5,5));
JButton meals = new JButton ("Meals");
JLabel label = new JLabel ("Welcome back!");
panel.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
panel.add(meals);
panel.add(label);
frame.add(panel);
}
}
That happens because you frame.setVisible(true); before adding any components to it. You should add the components to the frame first, and then, use the setVisible method.
panel.add(meals);
panel.add(label);
frame.add(panel);
frame.setVisible(true); //visible after components added
Fixed version of your code below. Hopefully it works. I tested it in my IDE.
import java.awt.ComponentOrientation;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;
public class MainMenu {
public static void main(String[] args) {
JFrame frame = new JFrame("Main Menu");
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(3, 2, 5, 5));
JButton meals = new JButton("Meals");
JLabel label = new JLabel("Welcome back!");
panel.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
panel.add(meals);
panel.add(label);
frame.add(panel);
frame.setSize(480, 720);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
I have an icon with text for JLabel, I am trying to get the text to vertically positioned at the bottom, but this can't work, this is my whole class:
import java.awt.FlowLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
public class Test {
public static void main(String[] args) {
JFrame frame = new JFrame("my frame");
frame.setLayout(new FlowLayout());
JLabel label = new JLabel("my label");
ImageIcon mouse = new ImageIcon("mouse.jpg");
label.setIcon(mouse);
label.setVerticalTextPosition(SwingConstants.BOTTOM);
frame.add(label);
frame.setVisible(true);
frame.setSize(500, 500);
}
}
import java.awt.FlowLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
public class Test {
public static void main(String[] args) {
JFrame frame = new JFrame("my frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new FlowLayout());
JLabel label = new JLabel("my label");
ImageIcon mouse = new ImageIcon("mouse.jpeg");
label.setIcon(mouse);
label.setHorizontalTextPosition(JLabel.CENTER);
label.setVerticalTextPosition(JLabel.BOTTOM);
frame.add(label);
frame.setVisible(true);
frame.setSize(500, 500);
}
}
Reference:
LabelTextPosition
I am trying to make a program where I have two JPanels inside a JFrame, one of which contains a canvas. I am trying to find a way to get that canvas to be constantly updating so that I could create something like a game inside the canvas. I was wondering how I could make it so that the JPanel with the canvas in it is constantly refreshing so that you can see when something is changed in the canvas. Here is my code:
package main;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main
{
private JFrame frame;
private JPanel mainPanel;
private JPanel gamePanel;
private JPanel sidePanel;
public void setup()
{
frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setVisible(true);
frame.setLocation(100, 50);
mainPanel = new JPanel();
Dimension d = new Dimension(800, 600);
mainPanel.setMaximumSize(d);
mainPanel.setMinimumSize(d);
mainPanel.setPreferredSize(d);
frame.add(mainPanel);
frame.pack();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.X_AXIS));
}
public void setupPanels()
{
gamePanel = new JPanel();
Dimension d = new Dimension(600, 600);
gamePanel.setMaximumSize(d);
gamePanel.setMinimumSize(d);
gamePanel.setPreferredSize(d);
gamePanel.setBackground(Color.RED);
mainPanel.add(gamePanel);
sidePanel = new JPanel();
d = new Dimension(600, 600);
sidePanel.setMaximumSize(d);
sidePanel.setMinimumSize(d);
sidePanel.setPreferredSize(d);
sidePanel.setBackground(Color.BLUE);
mainPanel.add(sidePanel);
}
public void setupGame()
{
GameArea game = new GameArea();
gamePanel.add(game);
game.start();
}
public static void main(String[] args)
{
Main main = new Main();
main.setup();
main.setupPanels();
main.setupGame();
}
So I'm trying to get the button on the bottom right and the text field taking up the bottom left but it keeps switching around for some reason. I think its borderLayout being stupid. I'm a noob at Java btw. Here's my code:
package textchat;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.*;
public class window extends JFrame{
public static void main(String[] args)
{
new window();
}
public window()
{
//Window Config
//JFrame frame = new JFrame();
Toolkit tk = Toolkit.getDefaultToolkit();
Dimension dm = tk.getScreenSize();
this.setSize(400,400);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setTitle("CALI V1");
this.setExtendedState(this.getExtendedState() | JFrame.MAXIMIZED_BOTH);
//this.setLayout(null);
int Width = this.getWidth();
//Panel(s)
JPanel Panel = new JPanel();
Panel.setLayout(new BorderLayout());
JPanel PanelSouth = new JPanel();
JPanel PanelEast = new JPanel();
JPanel PanelWest = new JPanel();
//button
JButton btn = new JButton("SEND");
//Text Area
JTextArea txt = new JTextArea(100 , 100);
txt.setText("TEXT IS HERE");
//Text Field
JTextField fld = new JTextField("Type Here",15);
//Adding to the panel
Panel.add(txt);
PanelSouth.add(PanelEast, BorderLayout.EAST);
PanelSouth.add(PanelWest, BorderLayout.WEST);
PanelEast.add(btn);
PanelWest.add(fld);
//adding to frame
this.add(Panel);
this.add(PanelSouth , BorderLayout.SOUTH);
this.setVisible(true);
}
}
While using BorderLayout in such a way kind of works, you should
not use it in such a way. Besides, your example has several issues.
For instance, you did not start the application on the EDT (Event Dispatch Tread).
Here is a working example that creates your inteded layout. It uses the powerful GroupLayout manager.
package com.zetcode;
import java.awt.Container;
import java.awt.EventQueue;
import javax.swing.GroupLayout;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class TextChatEx extends JFrame {
public TextChatEx() {
initUI();
}
private void initUI() {
JTextArea area = new JTextArea(15, 15);
JTextField field = new JTextField(15);
JButton sendButton = new JButton("Send");
createLayout(area, field, sendButton);
setTitle("Text chat");
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
private void createLayout(JComponent... arg) {
Container pane = getContentPane();
GroupLayout gl = new GroupLayout(pane);
pane.setLayout(gl);
gl.setAutoCreateContainerGaps(true);
gl.setAutoCreateGaps(true);
gl.setHorizontalGroup(gl.createParallelGroup()
.addComponent(arg[0])
.addGroup(gl.createSequentialGroup()
.addComponent(arg[1])
.addComponent(arg[2]))
);
gl.setVerticalGroup(gl.createSequentialGroup()
.addComponent(arg[0])
.addGroup(gl.createParallelGroup(GroupLayout.Alignment.BASELINE)
.addComponent(arg[1])
.addComponent(arg[2]))
);
pack();
}
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
TextChatEx ex = new TextChatEx();
ex.setVisible(true);
});
}
}
GroupLayout is a powerful layout manager; with this manager, you don't have to create a bunch of panels to create some basic layout.
public TextChatEx() {
initUI();
}
The GUI creation is delegated to the initUI() method. Rather than placing all the code into the constructor, we use a specialized method.
EventQueue.invokeLater(() -> {
TextChatEx ex = new TextChatEx();
ex.setVisible(true);
});
Each Swing application should be placed on the EDT. Failing to do this can lead to hard to find bugs in the future.