There are a lot questions on this, but they weren't able to help me or I didn't understand it..
Basically I want user to press the button before system goes back to main method. In this case if system goes back to main method, system will quit.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class test123 implements ActionListener{
JTable table;
JButton button;
JFrame frame;
public test123 (){
frame = new JFrame();
frame.setLayout(null);
button = new JButton("Finish");
button.setBounds(200, 10, 70, 40);
button.addActionListener(this);
frame.add(button);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
frame.setSize(600, 200);
frame.setVisible(true);
frame.setTitle("TEst123");
}
public void actionPerformed(ActionEvent e){
if(e.getSource() == button){
System.out.println("message....");
}
}
public static void main(String arg[]){
test123 gui = new test123();
System.exit(0);
}
}
Sorry if it was just me lacking the understanding and thank you for help.
EDIT:
Maybe I explained this incorrectly or displayed it incorrectly. Lets say if the system goes back to main system it will do something I don't want, therefor I want the user to press the button to go back to the main system or do "the thing". Sorry for bad explanation, including this one.
This class is separate from my work and I just used it to test stuff... In my project, user can choose from several buttons (lets say main method is the menu in this case). The user presses a button goes to a new window/frame, if the program doesn't pause or waits for button to be pressed, it will go back to main method.
The quick answer is what Andrew Thompson wrote in his comment:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTable;
public class test123 implements ActionListener {
JTable table;
JButton button;
JFrame frame;
public test123() {
frame = new JFrame();
frame.setLayout(null);
button = new JButton("Finish");
button.setBounds(200, 10, 70, 40);
button.addActionListener(this);
frame.add(button);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
frame.setSize(600, 200);
frame.setVisible(true);
frame.setTitle("TEst123");
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == button) {
System.out.println("message....");
// System.exit(0);
frame.dispose(); // better than exit
}
}
public static void main(String arg[]) {
test123 gui = new test123();
}
}
but Java class name should start with upper case test123 -> Test123 (but you can find a lot better name for sure).
Why not to extend JFrame also?
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
public class Test123 extends JFrame implements ActionListener {
private static final long serialVersionUID = 3378774311250822914L;
// private JTable table;
private JButton button;
// JFrame frame;
public Test123() {
// frame = new JFrame();
this.setLayout(null);
button = new JButton("Finish");
button.setBounds(200, 10, 70, 40);
button.addActionListener(this);
this.add(button);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setSize(600, 200);
this.setTitle("Test123");
this.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == button) {
System.out.println("message....");
// System.exit(0);
this.dispose();
}
}
public static void main(String arg[]) {
Test123 gui = new Test123();
}
}
Read more in Concurrency in Swing tutorial to find out how to deal with long running tasks out of dispatch thread...
From your question it seems, that you do not know how swing application behaves. You create a GUI and the you are waiting for user's input. So basically you do not care what was your program executing, when user pressed the button...
(and therefore it doesn't matter where it returns to)
Related
Hi I am new to programming and trying to figure things out as I go. Thanks in advance for the help.
I am trying to make a button in one class that when pressed, the other class knows.
Here is the first class that contains the testWindow method that I want to call in my other class.
import javax.swing.*;
import java.awt.event.*;
public class TestWindow {
public static void testWindow() {
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel text = new JLabel("this is a test!",SwingConstants.CENTER);
text.setBounds(0,30,300,50);
JButton button = new JButton("Start");
button.setBounds(100,100,100,40);
frame.add(text);
frame.add(button);
frame.setSize(300,200);
frame.setLayout(null);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//I don't know what to put here
}
});
}
}
And here is the second class where I want to use my testWindow method.
public class MainTest extends TestWindow {
public static void main(String[] arg){
testWindow();
//other stuff that happens when "start" is pressed
}
}
When I run the MainTest class, the testWindow appears as it should. But when the "start" button is pressed, I want to close that frame then do other actions in the main method. How would I go about that?
When I run the MainTest class, the testWindow appears as it should. But when the "start" button is pressed, I want to close that frame then do other actions in the main method. How would I go about that?
You're desiring the functionality of a modal dialog, a window that halts program flow until it has been dealt with. And in this situation you shouldn't be using a JFrame which does not allow for this type of modality, but rather a Swing modal dialog such as a JOptionPane or a JDialog that you create, make modal, and display. Then the GUI program flow halt until the dialog window is no longer visible.
If you do this, all the button's action listener has to do is to close the dialog window that holds it, that's it.
Side note: You're misusing inheritance here, as your MainTest class should most definitely not extend from the TestWindow class. While it may not matter in this simple code, it can and will cause problems in future code.
e.g.,
import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.Dialog.ModalityType;
import java.awt.event.*;
public class TestWindow {
public static void testWindow() {
// JFrame frame = new JFrame("test");
final JDialog frame = new JDialog((JFrame) null, "Test", ModalityType.APPLICATION_MODAL);
frame.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
// frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel text = new JLabel("this is a test!", SwingConstants.CENTER);
// text.setBounds(0, 30, 300, 50);
JButton button = new JButton("Start");
// button.setBounds(100, 100, 100, 40);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
frame.dispose();
}
});
int eb = 15;
JPanel panel = new JPanel(new BorderLayout(eb, eb));
panel.setBorder(BorderFactory.createEmptyBorder(eb, eb, eb, eb));
panel.add(text, BorderLayout.PAGE_START);
panel.add(button, BorderLayout.CENTER);
frame.add(panel);
frame.pack();
// frame.setSize(300, 200);
// frame.setLayout(null);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
and
import javax.swing.SwingUtilities;
public class TestTestWindow {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
TestWindow.testWindow();
System.out.println("Called after test window no longer visible");
});
}
}
I have a jframe that includes JButton.I have six buttons in this frame, but I don't know how to define action listener for this buttons.please help to solve this problem.
First you have to import the package java.awt.event.* to enable events. After the class name you have to add implements ActionListener so that the class can handle events. When you have created the buttons you have to add an actionlistener to each button. Since you haven't showed which code you use I make an example with a simple program that counts votes, if the user clicks the yesButton the votes are increased with 1 and if the user clicks the noButton the votes are decreased with 1.
Here is the code to add an ActionListener to each button:
yesButton.addActionListener(this);
noButton.addActionListener(this);
Then write the following code to handle the events:
public void actionPerformed(ActionEvent e) {
JButton src = (JButton) e.getSource();
if(src.getActionCommand().equals("Yes")) {
yesCount++;
} else {
noCount++;
}
label.setText("Difference: " + (yesCount - noCount));
}
If you have 6 buttons you need to have an if statement and then 5 "else if" statements instead of only an if and an else statement.
Have a look at the Java tutorials on how to use ActionListeners:
https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html
Here's a simple example:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Hello extends JPanel implements ActionListener {
JButton button;
public Hello() {
super(new BorderLayout());
button = new JButton("Say Hello");
button.setPreferredSize(new Dimension(180, 80));
add(button, BorderLayout.CENTER);
button.addActionListener(this); // This is how you add the listener
}
/**
* Invoked when an action occurs.
*/
public void actionPerformed(ActionEvent e) {
System.out.println("Hello world!");
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("Hello");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JComponent newContentPane = new Hello();
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
buttons have a method called addActionListener, use that for adding the action listener that you can implement for the click...
Example:
dummyButton = new JButton("Click Me!"); // construct a JButton
add(dummyButton); // add the button to the JFrame
dummyButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(" TODO Auto-generated method stub");
}
});
It's really simple.
I suppose you have an instance of your button, right? Let's say that instance is called myButton.
You can just add an action listener by calling addActionListener:
myButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// Do whatever you like here
}
});
Protip: next time you don't know what method to call, just type the instance name and .. Then, your IDE will show you all the methods you can call, unless you are not using an IDE. If that is the case, download one.
I have a frame, on this frame I have a Menu with About MenuItem. When we select it the program opens a new JPanel with texts and with OK button and the enabled status of parent panel is set to false.
And now comes a problem. When we click on OK, then I want to close this About panel, and I want to turn to parent panel, and I want to enable it!
Please tell me, how?
Consider using a WindowListener that reacts to the closing event of the about-dialog. You can add this in your frame or in the constructor of your dialog, just set the variables accordingly.
myDialog.addWindowListener(new WindowAdapter() {
#Override
public void windowClosed(WindowEvent e) {
parentFrame.setEnabled(true);
}
});
If you really only have a switching JPanel, use a ButtonListener.
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
//Execute when button is pressed
frame.setEnabled(true);
}
});
As mentioned in the comments, using a modal JDialog would be a more elegant way of solving the problem of disabling a parent frame while a dialog is active. Here is a tutorial.
Why don't you use simply a JOptionPane (particularly the showMessageDialog method)? You can specify there an Object (for example a JPanel) which will be presented in a modal dialog. Take a look at this sample code I've written for you (I've used a JButton, but it will be the same for JMenuItem):
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class AboutDialogDemo extends JFrame {
private final JButton btnAbout = new JButton("About...");
public AboutDialogDemo() {
final JFrame thisFrame = this;
btnAbout.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(thisFrame, new AboutPanel());
}
});
getContentPane().setLayout(new BorderLayout());
getContentPane().add(btnAbout, BorderLayout.PAGE_END);
pack();
}
public static void main(String[] args) {
AboutDialogDemo frame = new AboutDialogDemo();
frame.setSize(400, 400);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
class AboutPanel extends JPanel {
private final JLabel lblAbout = new JLabel("Sample about text");
public AboutPanel() {
setLayout(new BorderLayout());
add(lblAbout, BorderLayout.PAGE_START);
}
}
I hope you'll find it useful
I want to run this code that will create a window with a simple button on it. The program will run in Netbeans on a Mac but the problem is that it does not work. Here is the code below.
import javax.swing.JFrame;
public class Test {
public static JButton button(){
JButton button = new JButton("random button");
}
public static void main(String[] args) {
button();
new JFrame();
}
}
Please help me figure this out soon please. Thank you.
You're not adding the button to anything or displaying the JFrame. Your method returns a JButton object, but you're not doing anything with this object.
Create a JPanel
Add the JButton to the JPanel
Add the JPanel to the JFrame
Display the JFrame by calling setVisible(true)
Most important: Making up code and hoping it will magically work is not a successful heuristic for learning to program. Instead read the Swing tutorials which you can find here.
For example
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class MyTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JButton button = new JButton("Button");
JPanel panel = new JPanel();
panel.add(button);
JFrame frame = new JFrame("foo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
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);
}
});
}
}