Cancel button ? In java

[smasm]

Hi guys..

How can I write the set a cancel button ?

Ive two buttons ..

One of them the cancel button .. If the user click the cancel button I want to show new message ( you have clicked the cancel button) and exit the program ..

How can I write this code?

Thank you

[sunde887]

Look into action listeners-- http://download.oracle.com/javase/6/...nListener.html
Introduction to Event Listeners (The Java™ Tutorials > Creating a GUI With JFC/Swing > Writing Event Listeners)

[smasm]

Thanks for replying..
My English not good .. I'm trying to read and understand I can't
Please do you know the code ?

[Norm]

Do a Search on the forum for ActionListener for code samples

[smasm]

Yes I did .. I couldn't find ..
My English not good so I don't understand very fast
Please I need the code before 11:59 tonight

[Norm]

Yes I did .. I couldn't find ..

Strange. When I did a Search here it found hundreds of posts.
Are you sure you spelled it correctly?

[smasm]

since you posted I tried .. I found but i could it run it in my program .. kind of complecated ..
becuase most of the cases i find is pro and my program basic .. I need only one button
and there is one hour left to due time to submit my program .. please guys help :(

[Fubarable]

We'll be happy to help you, especially with any and all specific questions regarding your code, but your deadline is your problem, not ours, and certainly no one here is going to code this for you. Please show us what you've tried and ask any questions about any errors or problems you are having and we'll try to help.

[smasm]

Ok .. Thanks for the concern .. I'd like to see clue not codes .. I will be happy too .. I tried in youtube didn't fine .. I want lessen in video could not find too ... if you could give me a lessen in you tube .. thanks

[smasm]

We'll be happy to help you, especially with any and all specific questions regarding your code, but your deadline is your problem, not ours, and certainly no one here is going to code this for you. Please show us what you've tried and ask any questions about any errors or problems you are having and we'll try to help.

Ooh sorry guys i feel so bad maybe i am not suppose to write in here like this post
i just asked sorry again

[sunde887]

Like said, we don't mind helping, and I'm sure I have(and others as well) posted code which does something on a button click. The general way in which you get a button to do something is to add an ActionListener. When the button is clicked it will fire an ActionEvent, which will be grabbed by the ActionListener, which will handle to event.

Generally a button code will look something like this

JButton button = new JButton("Hello");
button.addActionListener(new ActionListener(){
  @Override public void actionPerformed(ActionEvent e){
     //do stuff here
  }
});

This is a lot more than I should be giving you, but it should be a sufficient start. More searching will definitely find the correct answer.

[mine0926]

Here is a link for JButton:
How to Use Buttons, Check Boxes, and Radio Buttons (The Java™ Tutorials > Creating a GUI With JFC/Swing > Using Swing Components)

Here is a link that might be helpful for you. Honestly, I visit this link very often. :)
The Really Big Index

[smasm]

Thanks alot guys for helping .. this is my program .. I kind understand now .. but feel like there is a problem .. where is it ?

import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JPanel;


public class Program3 {
        			
	public static void main(String[] args) 
	
	{

		// declare variables
		int sum = 0;
		int max=0, min= 0;
		//  initialize it one time.
		boolean firstIteration = true;


		// the for loop
		for ( int i=1; i<=4; i++)
			
		{
			//each inputted number will stores here
			String userInput = JOptionPane
			    .showInputDialog("Enter an integer");
            // to converse the string to int
			int value = Integer.parseInt(userInput);
			       
		    if(firstIteration)
		    {
				// the variables
		        sum = value; 
		    	max = value;
		    	min = value;
		    	firstIteration = false;
		    	
		    }
		    else
		    {
		    	//add to sum 
		    	sum += value; 
		    } 

		     //conditional statement
            //if inputted number is smaller than our min then exchange it.
		    if(value < min)
		    {
		        min = value; 
		    }
		    
		     //conditional statement
            //if inputted number is bigger than our max then exchange it.
		    if(value > max)
		    {
		        max = value; 
		    }
	}
		// calculating the averege by extracted the sum by 4
		double averge = sum / 4.0;

		   JOptionPane.showMessageDialog(null," Max is " + max + " \nMin is " + min + 
				                      "\nSum is " + sum + " \nAverage is " + averge
				               , "Program 3", JOptionPane.PLAIN_MESSAGE);


	
	JButton button = new JButton("cancel");
	button.addActionListener(new ActionListener(){
	


			JButton button = new JButton();
			button.setVisible(true);
			button.setSize(250,250);
			button.setDefaultCloseOperation(JButton.EXIT_ON_CLOSE);
			
			JPanel p = new JPanel();
			JButton b1 = new JButton ("Action Listener");
			button.addActionListener(new ActionListener(){
				
				public void actionPerformed(ActionEvent e)
				{
					JOptionPane.showMessageDialog(null, "cancel button clicked")
				
				
			});
			
			p.add(b1);
			button.add(p);
		}
	});
		   
			System.exit(0); // program end

    }	

}

[mine0926]

You did not tell us what problem you are encountering.
And its hard to read, use code tags instead.

Looking at the code I saw that you declare button two(2) times. I think you do not intend to create new JButton when you click the "cancel" button, right?

JButton button = new JButton("cancel");
button.addActionListener(new ActionListener(){



JButton button = new JButton();
button.setVisible(true);
button.setSize(250,250);
button.setDefaultCloseOperation(JButton.EXIT_ON_CL OSE);

JPanel p = new JPanel();
JButton b1 = new JButton ("Action Listener");
button.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e)
{
JOptionPane.showMessageDialog(null, "cancel button clicked")


});

[smasm]

right .. I was thinking that why do I have to create a new button and I do have it .. the result of the program is attached .. I just need action for it

[Fubarable]

You're using a JOptionPane.showInputDialog and this changes everything. In this case you must check what the JOptionPane method returns. If it is null, then the user pressed cancel, and then you show your other JOptionPane that states that the user pressed the cancel button. There's no need to mess with ActionListeners with this. Again, just check the userInput variable to see if it is null (if it == null).

[smasm]

You're using a JOptionPane.showInputDialog and this changes everything. In this case you must check what the JOptionPane method returns. If it is null, then the user pressed cancel, and then you show your other JOptionPane that states that the user pressed the cancel button. There's no need to mess with ActionListeners with this. Again, just check the userInput variable to see if it is null (if it == null).

this is great ..

you mean I can use something like this

JOptionPane.CANCEL_OPTION(null,"Cancel was selected. Program will exit");

should I put it in line 67 ?

[smasm]

You're using a JOptionPane.showInputDialog and this changes everything. In this case you must check what the JOptionPane method returns. If it is null, then the user pressed cancel, and then you show your other JOptionPane that states that the user pressed the cancel button. There's no need to mess with ActionListeners with this. Again, just check the userInput variable to see if it is null (if it == null).

this is great ..

you mean I can use something like this

JOptionPane.CANCEL_OPTION(null,"Cancel was selected. Program will exit");

should I put it in line 67 ?

[Fubarable]

No, not quite. For one thing, JOptionPane.CANCEL_OPTION is an int and you can't call it like it's a method. I meant something more like this:

      String test = JOptionPane.showInputDialog(null, "Enter Something");
      if (test == null) {
         // the user pressed cancel. Show a JOptionPane.
      } else {
         // they pressed OK and the test variable has useful information
      }

[smasm]

I'm sorry my computer is too slow .. I'm replying from my iPad ,, I've to submit the program before 12
And I'm trying to run it .. It's frizzing now .. as soon as it work I'll test ittttt ...