ActionScript: Classes, Properties, EventHandler Methods, Datatypes & Control Structures

1. ActionScript: Classes, Properties, EventHandler Methods, Datatypes & Control Structures MMP 220 Multimedia Programming This material was prepared for students in MMP220 Multimedia Programming as as part of a curriculum redesign project funded by National Science Foundation grant #0511209 Co PI’s Christopher Stein and Jody Culkin BMCC CUNY http://teachingmultimedia.net

2. Interface of Flash

3. ActionScript Window

6. Concepts we learned in Alice and will be using in ActionScript:  Classes  Properties  Event handler methods  Control Structures  Datatypes

7. Classes • A class is a blueprint for an object. When you create an object of a particular class, you are creating an instance of that class. Example in ActionScript: MovieClip class

8. Properties • Properties are attributes of an object. Each object has specific properties that have to do with the nature of the class of which it is an instance. Properties of the MovieClip class include _alpha (opacity), _width, _x (horizontal position), _y (vertical position).

9. Event Handler Methods: • Event Handler Methods are specially named methods that can be used with certain objects when the corresponding event occurs. example: circle_mc.onRelease function():Void{ circle_mc._x += 10; }

10. Control Structures • control the flow of code execution. If statements, while, and for loops are examples in ActionScript. example: if(circle_mc._alpha > 0){ circle_mc._ alpha -= 2; }

11. Datatypes • datatypes refer to what type of values various types of data might hold. In ActionScript, there are primitive datatypes and reference datatypes. • Primitive datatypes include number, string, boolean. Reference datatypes include all objects, such as MovieClips.

12. Alice/ActionScript

13. Assignment • Read Chapters 2 and 3 of the Flash ActionScript Bible • Make a movie in Flash where you click something and something happens- using ActionScript. You can change properties, such as _x and _y, change size and opacity.