/*
                Name:           Chris Johnson
                                        johnson@dcs.gla.ac.uk
 
                Last modified:  21/1/2000
 
                Description:
		Creates some lights that are controlled by three buttons.

		From an idea originally suggested by: Quintin Blane
		qablane@surfaid.org
		
		Updated to AWT 1.1 21/1/2000
*/

import java.awt.*;
import java.awt.event.*;
import java.applet.Applet;

public class Lights extends Applet {
	
	Panel controls = new Panel(); // for the red, green and ambre buttons

   static final String Red_Command = "red";
   static final String Amber_Command = "amber";
   static final String Green_Command = "green";

	Button Red_Button = new Button("Red");  // create new buttons
	Button Amber_Button = new Button("Amber"); 
	Button Green_Button = new Button("Green");



	Traffic_Lights lights = new Traffic_Lights(this);
	// create some lights that will appear on this applet
	
	
	public void init(){
		
		setLayout(new BorderLayout());
		  
		Red_Button.setActionCommand(Red_Command);
		Amber_Button.setActionCommand(Amber_Command);
		Green_Button.setActionCommand(Green_Command);
				  
		controls.setLayout(new FlowLayout(FlowLayout.LEFT));
		controls.add(Red_Button);
		controls.add(Amber_Button);
		controls.add(Green_Button);
		
		add("North", controls);
		add("Center", lights);
	
	  //initialise the listener
    Traffic_Light_Event Tle = new Traffic_Light_Event();
 
    //add the listener to each object
    Red_Button.addActionListener(Tle);
    Green_Button.addActionListener(Tle);
    Amber_Button.addActionListener(Tle);
   
                
		validate();

 
   }
 
        //inner class actionlistener
     class Traffic_Light_Event implements ActionListener 
        {
                public void actionPerformed(ActionEvent event)
                {
                        if(event.getActionCommand() == Red_Command) 
                        //uses the action command text
                                lights.set_lights("Red");
                        else if (event.getActionCommand() == Green_Command) 
                        //if not set then it uses button text
                                lights.set_lights("Green");
                        else if (event.getActionCommand() == Amber_Command)
                                lights.set_lights("Amber");
 
                }
 
        }
  
}