OOLessonPlans

Ms Gold

2/13

Introduction to Object Oriented Programming

Lesson Plan 18 -Moving Car - Java Application vs Java Applet

Mass Framework:

Standard 1:

Demonstrate proficiency in the use of computers and applications as well as an understanding of concepts underlying hardware, software, and connectivity.

Standard 2:

Demonstrate responsible use of technology and an understanding of ethics and safety issues in using electronic media.

Standard from Technology/Engineering Standards for a Full First-Year Course in Grades 9 or 10

Broad Concept: Engineering design involves practical problem solving, research, development, and invention and requires designing, drawing, building, testing and redesigning.

Learning Objective: To try to grapple with the issues surrounding the future of digital media brought to light by the recent storm of WikiLeaks activities.

Learning Experience:

Objective: To understand and then implement Event Listeners.
3 minute papers - Why we need an Event Listener to in our programs? What examples of programs that need Event Listeners? Why do we need an Event Listener in the car moving program?
- In general programs that have to deal with possible inputs - Not just user Inputs -in random order.
- Java's windowing toolkits generates a huge number of events - You the programmer tells the toolkit which events you are interested in and which objects to notify when one of the events occurs.
  - 1) first tell which event to receive - find the class that it belongs to
    - the methods of the event listener contain instructions that you want to have executed when the event occurs.
  - 2) To install a listener, you need to know the event source. The event source is the user-interface component that generates a particular event.
    - You add an event listener object the appropriate event source. The even source calls the appropriate methods of all attached event listeners.
You are going to implement the car mover just like the Button Clicker - as an inner class
What is an inner class - and why do we use it
- class TimeListener implements ActionListener
  {
  - public void actionPerformed(ActionEvent event)
    {
    - component.moveCarBy(1,0);
  - }
- }
- Read Information on How a Timer is used: http://download.oracle.com/javase/1.5.0/docs/api/javax/swing/Timer.html
  
  ActionListener listener = new TimeListener();
  final int DELAY =10;
  Timer t = new Timer(DELAY, listener);
  t.start();
- On the Web Site has been the answer all along - here are links to reading
  - Timers and Threads faqs
- applets are explained on the games tutorial Web site