Develop Reference

Java JButton - making simple menu

Hi take a look on this code:
package arkanoid;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.event.*;
public class Arkanoid extends JFrame
{
private static final long serialVersionUID = 6253310598075887445L;
static JFrame frame;
static class Action1 implements ActionListener {
public void actionPerformed (ActionEvent e) {
//frame = new JFrame("Arkanoid");
frame.setLocationRelativeTo(null);
frame.setIgnoreRepaint(true);
frame.setResizable(false);
frame.setVisible(true);
frame.setSize(500,400);
frame.add(new Gra());
}
}
static class Action2 implements ActionListener {
public void actionPerformed (ActionEvent e) {
frame.dispose();
System.exit(0);
}
}
public static void main(String[] args)
{
//new Arkanoid();
frame = new JFrame("Arkanoid");
frame.setSize(500,400);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("Arkanoid BETA");
frame.setLocationRelativeTo(null);
frame.setIgnoreRepaint(true);
frame.setResizable(false);
frame.setVisible(true);
JPanel panel = new JPanel();
frame.add(panel);
JButton button = new JButton("Nowa Gra");
panel.add(button);
button.addActionListener (new Action1());
JButton button2 = new JButton("Wyjscie");
panel.add(button2);
button2.addActionListener (new Action2());
}
}
This code almost works, I want to make a button2 a quit button working like X button in top right frame's icons and button1 need to open a Gra() in the same window. When im doing it like this it isnt work fine:/ i need to click 2 times on button1 to go to Gra() and what is more KeyListeners in Gra() arent working :(
Im new in buttons, frames and panels in java so please help with this code. Correct it please.

There are a number of fundamental problems with your code, the least of which is why your button1 requires 2 clicks.
However, for your problem you should try rearranging the order of your button1 listener, so that your Component is added to the frame first, before setting it to be visible. An example that should work:
static class Action1 implements ActionListener {
public void actionPerformed (ActionEvent e) {
frame.add(new Gra());
frame.revalidate();
}
}
Note you have already set the size, location etc of frame in main, so there is no need to set them again every time the button is clicked.
I stress that there are more important problems with your code than this issue. You should take a look at Java's Modifier Types (static does not seem applicable here), as well as object-oriented concepts such as inheritance (you define your Arkanoid class to extend JFrame, yet have a JFrame object as a class variable).

I want to make a button2 a quit button working like X button in top right frame's
You can use the ExitAction class found in Closing an Application.
For other examples of how to use buttons read the Swing tutorial on How to Use Buttons. This is the place to start for all you Swing related questions.

There are many problems with your code. I've refactored it a little. With below code & #ricky116 answer I think you should get all of them.
import javax.swing.*;
import java.awt.Color;
import java.awt.event.*;
public class Arkanoid extends JFrame
{
public Arkanoid() {
super("Arkanoid");
setSize(500,400);
setTitle("Arkanoid BETA");
setLocationRelativeTo(null);
setResizable(false);
final JPanel panel = new JPanel();
setContentPane(panel);
panel.add(new JButton(new AbstractAction("Nowa Gra") {
public void actionPerformed (ActionEvent e) {
panel.removeAll();
panel.add(new Gra());
panel.revalidate();
panel.repaint();
}
});
panel.add(new JButton(new AbstractAction("Wyjscie") {
public void actionPerformed (ActionEvent e) {
Arkanoid.this.setVisible(false);
}
});
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Arkanoid frame = new Arkanoid();
frame.setVisible(true);
}
});
}
}

Java- How to add more textfields by clicking a button?

I have created a frame in Java which has some textfields and buttons in it. Assuming that user wants more textfields (for example to add more data), I want to put a button and when a user clicks the button, then a new textfield should appear. then user can fill data in it and again by clicking that button another textfield should appear.
How can I do this ? What code I need to write for the button to show more and more text fields by clicking button?
Thank you !

It would be wise that instead of adding components to your JFrame directly, you add them to a JPanel. Though related to your problem, have a look at this small example, hopefully might be able to give you some hint, else ask me what is out of bounds.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JFrameExample
{
private JFrame frame;
private JButton button;
private JTextField tfield;
private String nameTField;
private int count;
public JFrameExample()
{
nameTField = "tField";
count = 0;
}
private void displayGUI()
{
frame = new JFrame("JFrame Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(0, 1, 2, 2));
button = new JButton("Add JTextField");
button.addActionListener(new ActionListener()
{
#Override
public void actionPerformed(ActionEvent ae)
{
tfield = new JTextField();
tfield.setName(nameTField + count);
count++;
frame.add(tfield);
frame.revalidate(); // For JDK 1.7 or above.
//frame.getContentPane().revalidate(); // For JDK 1.6 or below.
frame.repaint();
}
});
frame.add(button);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
new JFrameExample().displayGUI();
}
});
}
}

Supposing that you have a main container called panel and a button variable button which is already added to panel, you can do:
// handle the button action event
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// create the new text field
JTextField newTextField = new JTextField();
// add it to the container
panel.add(newTextField);
panel.validate();
panel.repaint();
}
});
When adding the new text field, you may need to mention some layout related characteristics, depending on the layout manager you are using (for instance if you use GridBagLayout, you will need to specify the constraints).

Need to resize the window for program to work

Here is the code of my Layout class.
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
public class Layout extends JFrame {
private JButton lb;
private JButton cb;
private JButton pb;
private FlowLayout layout;
private Container container;
public Layout() {
super("The Title");
layout = new FlowLayout();
container = new Container();
setLayout(layout);
//*Left
lb = new JButton("L");
add(lb);
lb.addActionListener(
new ActionListener(){
public void actionPerformed(ActionEvent event){
layout.setAlignment(FlowLayout.LEFT);
layout.layoutContainer(container);
}
}
);
//*Center
cb = new JButton("C");
add(cb);
cb.addActionListener(
new ActionListener(){
public void actionPerformed(ActionEvent event){
layout.setAlignment(FlowLayout.CENTER);
layout.layoutContainer(container);
}
}
);
//*Right
pb = new JButton("R");
add(pb);
pb.addActionListener(
new ActionListener(){
public void actionPerformed(ActionEvent event){
layout.setAlignment(FlowLayout.RIGHT);
layout.layoutContainer(container);
}
}
);
}
}
I'm learning java through thenewboston youtube tutorials (this code is from this tutorial). But this one doesn't work like it should. When I click the right button (R) it should drag all the buttons to the right side of the window instantly. It doesnt. However when I click that right button and then forcibly resize the window then it do what it should. By adding setResizable(false) in the main method I cant resize the program so it doesnt work.
What have I done wrong?
Forgive me for my poor English btw.

replace
container = new Container();
by
container = getContentPane();

The simplest way would be to set a new FlowLayout and call invalidate():
setLayout(new FlowLayout(FlowLayout.LEFT));
invalidate();
validate();
Updating the current FlowLayout has no effect.

Detect removal of component

I create a Popup using the PopupFactory.getPopup method. According to the documentation, I am required to call the hide() method on the popup when it is no longer needed.
In my application, the popup is the child of a JLabel which may be removed from the current frame in a number of different situations. (Either the JLabel itself or one of its parent containers is removed.) Rather that calling hide() in every single place (and making the Popup object available in all these places) I would prefer to be able to detect the removal of the JLabel or one of its parent containers.
How can I detect the removal? I naively assumed that the removal of a component meant the removal/hiding of its children, but as the code below shows, the popup survives the removal of the JLabel.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Xyzzy extends JFrame {
static Xyzzy frame;
static JPanel panel;
static JLabel text1;
static JLabel text2;
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
frame = new Xyzzy();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(new BoxLayout(frame.getContentPane(), BoxLayout.PAGE_AXIS));
panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.LINE_AXIS));
frame.add(panel);
text1 = new JLabel("text1");
text2 = new JLabel("text2");
panel.add(text1);
frame.add(new JButton(new AbstractAction("Add popup") {
public void actionPerformed(ActionEvent e) {
PopupFactory factory = PopupFactory.getSharedInstance();
Popup popup = factory.getPopup(text1, new JLabel("POPUP"),frame.getX()+300,frame.getY()+300);
popup.show();
}
}));
frame.add(new JButton(new AbstractAction("New label") {
public void actionPerformed(ActionEvent e) {
panel.remove(text1);
panel.add(text2);
panel.revalidate();
}
}));
frame.setSize(600, 600);
frame.setVisible(true);
}
});
}
}
This code creates a JFrame displaying the text "text1" and two buttons. If you press the button labeled "Add popup", a Popup with the text "POPUP" appears in the window. This Popup is a child of text1. Press the "New label" button and "text1" is removed from the display, but the Popup survives.
I need to be able to detect when text1 or the containing panel is removed so that I can hide the popup. I want to avoid adding code where the actual remove() method is called.

You can use HierarchyListener:
public void actionPerformed(ActionEvent e) {
PopupFactory factory = PopupFactory.getSharedInstance();
final Popup popup = factory.getPopup(text1, new JLabel("POPUP"),frame.getX()+300,frame.getY()+300);
text1.addHierarchyListener(new HierarchyListener() {
public void hierarchyChanged(HierarchyEvent e) {
if (e.getID() == HierarchyEvent.HIERARCHY_CHANGED
&& (e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED) != 0) {
popup.hide();
}
}
});
popup.show();
}

Change state of toggle button from another button

I'm creating a Java GUI using Swing with Eclipse and Window Builder Pro. I'm using JButtons and JToggleButtons. I want to change toggle button's state from another button.
For example, when I click the clear grid, all the toggle buttons will be 'not selected'.
How can I do this? What are the methods that I have to use for toggle buttons and buttons?

toggleButton.setSelected(boolean b)
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractButton;
import javax.swing.JFrame;
import javax.swing.JToggleButton;
public class JToggleButtonAction {
public static void main(String args[]) {
JFrame frame = new JFrame("Selecting Toggle");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JToggleButton toggleButton = new JToggleButton("Toggle Button");
final JToggleButton toggleButton1 = new JToggleButton("Another Toggle Button");
ActionListener actionListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent actionEvent) {
AbstractButton abstractButton = (AbstractButton) actionEvent.getSource();
boolean selected = abstractButton.getModel().isSelected();
System.out.println("Action - selected=" + selected + "\n");
toggleButton1.setSelected(selected);
}
};
toggleButton.addActionListener(actionListener);
frame.add(toggleButton, BorderLayout.NORTH);
frame.add(toggleButton1, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
}
}

Add actionListener to your JButton and in actionPerformed(ActionEvent) method change the state of all JToggleButtons. Make sure all your JToggleButton is accessible in this method. A simple example will be..
JFrame frame = new JFrame("Panel image demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setLayout(new FlowLayout());
final JToggleButton[] button = new JToggleButton[10];
for (int i = 0; i < button.length; i++) {
button[i] = new JToggleButton("Toggle Us");
frame.add(button[i]);
}
JButton jButton = new JButton("Toggle that button");
jButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (JToggleButton jToggleButton : button) {
jToggleButton.setSelected(!jToggleButton.isSelected()); // <-- this will change the state of toggle button
}
}
});
frame.add(jButton);
frame.setVisible(true);

Register an ActionListener to the JButton instance and make sure you can access the toggle buttons therein to manipulate their state.

i was looking for this, this might help somebody out
B1.setSelected(false);
i made a method that make all my button false (unselect the toggles when i wanted it)