import java.awt.*; // older GUI library, has layout stuff for components
import java.awt.event.*; // events
import javax.swing.*; // swing is a library of GUI components

// example of buttons with actionlisteners
// class extends JFrame, so it is its own window
// class is an ActionListener - will provide a method to respond to an event
public class Outer extends JFrame implements ActionListener{

	// keep count of how many times each button was clicked
	private int times1;
	private int times2;
	private int times3;
	private JButton button1;
	private JButton button2;
	private JButton button3;
	
	// constructor does all setup of window and buttons
	public Outer() {
		// call the JFrame constructor
		super("I have a button");
		
		times1 = 0;
		times2 = 0;
		times3 = 0;

		// using methods inherited from JFrame
		// close the program if we close the window
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		// width, height in pixels -- better to use pack()
		// setSize(400, 80);
		// put new added widgets in from left to right
		setLayout(new FlowLayout());

		
		// button using an inner class as actionlistener
		button1 = new JButton("Button 1 - " + times1);
		button1.addActionListener(new Inner());

		
		// button using an anonymous inner class as actionlistener
		button2 = new JButton("Button 2 - " + times2);
		button2.addActionListener( 
			// the anonymous inner class to respond to clicks from button 2
			// since it it inner class, it can access times2 and button2
			new ActionListener() { // implementing this interface
				public void actionPerformed(ActionEvent e) {
					times2 ++;
					button2.setText("Button 2 - " + times2);
				}
			}
		);				

		
		// button using the class it is in as actionlistener
		button3 = new JButton("Button 1 or 3 - " + times3);
		button3.addActionListener(this);
		// also use this actionlistener if button 1 is pushed
		// button 1 has two actionlisteners triggered with every click
		button1.addActionListener(this);
		
		
		// put the buttons in the window
		add(button1);
		add(button2);
		add(button3);

		// size based on widgets
		pack();
		// make the window visible
		setVisible(true);
	}

	// class to respond to clicks from button 1
	// since it is inner class, it can access times1 and button1
	private class Inner implements ActionListener {
		public void actionPerformed(ActionEvent e) {
			times1 ++;
			button1.setText("Button 1 - " + times1);
		}
	}

	// outer can be an actionlistener too
	// respond to clicks from button 1 or 3
	public void actionPerformed(ActionEvent e) {
		times3 ++;
		button3.setText("Button 1 or 3 - " + times3);
	}
	
	// main to launch the GUI
	public static void main(String[] args) {
		// two separate windows, with their own variables
		// and own inner classes separate from each other
		Outer outerEx1 = new Outer();
		Outer outerEx2 = new Outer();
	}
}