[SOLVED] Actionevent problem

[Cymro]

I have decided to shy away from IDEs to try my hand at a text editor (proper? ) approach to coding. However, a major problem:

Code:

import javax.swing.*;
import java.awt.*;

public class SandBox extends JFrame{

private static void makeGUI(){
	JFrame frame = new JFrame("Test");
	frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	frame.setLayout(new FlowLayout());
	
	JButton button = new JButton("Login");
	button.addActionListener(new ActionListener());
	frame.add(button);
	
	frame.pack();
	frame.setVisible(true);

}

	public void actionPerformed(ActionEvent e){
		System.out.println("Test");
	}



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

}

when this code compiles, it informs me that it “cannot find symbol” whenver ActionEvent/Listener is referred to. Not exactly what was meant to happen

[hardwired]

Code:

C:\jexp>javac sandboxrx.java
sandboxrx.java:21: cannot find symbol
symbol  : class ActionEvent
location: class SandBoxRx
    public void actionPerformed(ActionEvent e){
                                ^
sandboxrx.java:14: cannot find symbol
symbol  : class ActionListener
location: class SandBoxRx
        button.addActionListener(new ActionListener());
                                     ^
2 errors

1 - import java.awt.event.*;
recompile:

Code:

C:\jexp>javac sandboxrx.java
sandboxrx.java:15: java.awt.event.ActionListener is abstract; cannot be instantiated
        button.addActionListener(new ActionListener());
                                 ^
1 error

Code:

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

public class SandBoxRx implements ActionListener {
    private void makeGUI(){
        JFrame frame = new JFrame("Test");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        JButton button = new JButton("Login");
        // The jvm is looking for the "ActionListener" class
        // on your classpath. Since ActionListener is a Java
        // class then this is doubly confusing.
        button.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("anonymous ActionListener");
            }
        });
        button.addActionListener(this);
        button.addActionListener(new SandBoxListener());
        frame.add(button);

        frame.pack();
        frame.setVisible(true);
    }

    // Implementation of ActionListener interface
    // implemented by the enclosing class.
    public void actionPerformed(ActionEvent e){
        System.out.println("Enclosing class-implemented ActionListener");
    }

    private class SandBoxListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            System.out.println("SandBoxListener ActionListener");
        }
    }

    public static void main(String[] args){
        EventQueue.invokeLater(new Runnable(){
            public void run(){
                new SandBoxRx().makeGUI();
           }
        });
    }
}

[Cymro]

Thank you very much. It all works now

[CaptainMorgan]

I applaud your goal of working with your text editor instead of an IDE. It's my belief it will make you a better programmer- once you've got the fundamentals solidly down, you should move back to the IDE or only move back to the IDE when time constraints and many lines of code are required. They help to reduce production times.

Now that your problem is sufficiently solved, take the time to mark your thread as "Solved" using the Thread Tools at the top.

Best of luck.