Hello - I've used a for loop to fill an array of JButtons with text. Each JButton contains a letter of the alphabet. I've been successful in doing this and adding each button to a panel I created. But my problem is that I've tried, unsuccessfully, to add ActionListener's to each of the JButtons. When I press the button it should print the text in the JButton.

Any idea's?

You can use the getSource() method of the ActionEvent to get a reference to the button that was clicked. You will need to cast it to JButton yourself to use it, since getSource() returns Object.

You can also try using the getActionCommand() inside the actionPerformed part of the listener.
This function returns a String so you should be able to avoid casting.

or the obvious guys....

add the actionlistener to the loop---or even better, separate the creation of the button all together...shazam!

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;


public class ButtonClicker extends JFrame {

	private static final long serialVersionUID = 1L;
	private JTextField output = new JTextField();
	private ArrayList<JButton> list = new ArrayList<JButton>();

	public ButtonClicker() {
		configLayout();
		configFrame();
	}
	
	private void configFrame() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setVisible(true);
		setResizable(false);
		setLocation(400, 200);
		pack();
	}
	
	private void configLayout() {
		getContentPane().setLayout(new BorderLayout());
		output.setHorizontalAlignment(SwingConstants.RIGHT);
		output.setFocusable(false);
		getContentPane().add(output, BorderLayout.NORTH);

		JPanel panel = new JPanel();
		getContentPane().add(panel, BorderLayout.CENTER);
		panel.setLayout(new GridLayout(3, 3));
		
		for (int i = 1; i <= 9; i++)
			panel.add(createButton(i));

		getContentPane().add(createButton(0), BorderLayout.SOUTH);
	}
	
	private JButton createButton(final int text) {
		JButton button = new JButton(Integer.toString(text));
		button.setFocusable(false);
		button.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				output.setText(output.getText() + text);
			}
		});
		list.add(button);
		return button;
	}
	
	public static void main(String[] args) {
		new ButtonClicker();		
	}
}

just some ..., no FW (that's about e.getSource())

- have to create GUI on EDT (main method)
- have to place, size, pack TopLayoutContainer, and then visible container
- you are set LayoutManager correctly, then there is no longer needed something about ContentPane, (hmmmm, sure backGround Color, but just for empty container)
- if you want to create thread safe outPut from Listener, then you have put

outPut to Swing Action or
outPut pack to SwingUtilities.invokeLater(...

there is ...

import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import javax.swing.*;

public class ButtonClicker extends JFrame {

    private static final long serialVersionUID = 1L;
    private JTextField output = new JTextField();
    private ArrayList<JButton> list = new ArrayList<JButton>();

    public ButtonClicker() {
        configLayout();
        configFrame();
    }

    private void configFrame() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);
        setLocation(400, 200);
        pack();
        setVisible(true);
    }

    private void configLayout() {
        setLayout(new BorderLayout());
        output.setHorizontalAlignment(SwingConstants.RIGHT);
        output.setFocusable(false);
        add(output, BorderLayout.NORTH);
        JPanel panel = new JPanel();
        add(panel, BorderLayout.CENTER);
        panel.setLayout(new GridLayout(3, 3));
        for (int i = 1; i <= 9; i++) {
            panel.add(createButton(i));
        }
        add(createButton(0), BorderLayout.SOUTH);
    }

    private JButton createButton(final int text) {
        JButton button = new JButton(Integer.toString(text));
        button.setFocusable(false);
        button.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                Runnable doRun = new Runnable() {

                    public void run() {
                        output.setText(output.getText() + text);
                    }
                };
                SwingUtilities.invokeLater(doRun);
            }
        });
        list.add(button);
        return button;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            public void run() {
                ButtonClicker bC = new ButtonClicker();
            }
        });
    }
}

Yo - cheers all for reply's. I examined all entries and made up my own. It does the job so here is my simple code for solving my problem:

// Constructor for panel class; added to main frame in separate class

public dummyPanel()
	{
		int j = 0;
		
		while( j < 3 )
		{
			add( crteBttn( ""+j ) );
			j++;
		}
	}

// Create and add the Button to the screen
public JButton crteBttn( String text )
	{
		final JButton aBttn = new JButton( "Button "+text );
		aBttn.addActionListener( new ActionListener()
		{
			public void actionPerformed( ActionEvent evt)
			{
				String txt = aBttn.getText();
				System.out.println( txt );
			}
		});
		return aBttn;
	}

I think that not, it doesn't, what will be happends if you'll need to set separated action from each JButton, isn't it

mKorbel -- read the poster's original post. They just need it to create buttons A through Z that update a Label. Where are you getting that they need threading and separate actions? Regardless---the OP solved this thread.

Best of luck Katana, your code looks great.

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