ActionScript: Classes, Properties, EventHandler Methods, Datatypes

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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 PIs Christopher
Stein and Jody Culkin BMCC CUNY
http//teachingmultimedia.net
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Interface of Flash
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ActionScript Window
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Concepts we learned in Alice and will be using in
ActionScript

• ? Classes
• ? Properties
• ? Event handler methods
• ? Control Structures
• ? Datatypes

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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

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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).

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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

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Control Structures

• control the flow of code execution. If
  statements, while, and for loops are examples in
  ActionScript.
• example
• if(circle_mc._alpha gt 0)
• circle_mc._ alpha - 2

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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.

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Alice/ActionScript
Alice Examples ActionScript Examples
Classes Penguin, Bunny, IceSkater MovieClip, TextField, Button, Math
Properties color, opacity, isShowing _xScale, _y, _visible, _alpha
Event Handler Methods When Enter is typed, do Cow.walk times1 speed2 square_mc.onEnterFramefunction()Void square_mc._x10
Control Structures if/then, do in order, while if, while, for loop
Datatypes Object, Number, String Object, Number, String
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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.