2. Please turn in homework
• Last weekʼs homework was to create a
Web page that used jQuery
• Put files in a folder with your lastname
and first initial
• Example:
smith-h
myPage.html
pic1.jpg
5. Basic ActionScript
• Click the first Keyframe in the
timeline to select it
• Open the ActionScript window by
going to Window > Actions
6. Trace output
trace(“Hello World!”);
• Go to Control > Test Movie to test out
your ActionScript
• trace helps troubleshoot code by
sending notes to you in the Output
window
7. Screen Output
var myText:TextField = new TextField();
myText.text = "Hello World!";
addChild(myText);
• The first line creates a new area to display
the text, a textfield
• The second line puts your text in the
textfield
• The third line adds the textfield to the stage
8. Display Objects
var myText:TextField =
new TextField();
• Visual elements that appear in
ActionScript
• Such as textfields, graphics, buttons,
movie clips, and user interface
components
9. Object Properties
myText.text =
"Hello World!";
• Objects have properties
• Each object has itʼs own properties
• Properties of the objects can be
changed directly
10. Display Lists
addChild(myText);
• Creating objects does not add them
to the stage. You must place them
directly.
11. The Stage
• The main movie area where
everything takes place that the user
will see
12. The Library
• Where youʼll store all the media
thatʼs associated with your Flash
movie
15. ActionScript Window
• Wonʼt use most of the buttons until
you get used to ActionScript
• Use the Show/Hide Toolbox button to
collapse the left column
• Disable Script Assist for now
16. Comments
// single comment
/*
multi-line comment
*/
• Comments are notes you can add for
yourself or other developers
• Comments can also be used to “turn off”
code
17. Use descriptive naming
• Variable names:
tennisBall,
userRacket, userScore
• Function names: hitBall(
),
calcScore( ), headPunch( )
18. Use functions
• Use functions for repetitive tasks or
tasks that appear in many places
public function showTime() {
timeDisplay.text =
“Time: ” + timeElapsed;
}
showTime();
22. if-else statements
if (this is true) {
then do this
} else if (this is true) {
then do this
} else {
do this
}
23. Equal, not equal, or...
• Assume this: a = 1;
b = 2;
c = 1;
• These are true statements:
(a == c) a is equal to c
(a != b) a is not equal to b
(a == 1 || c == 1) a is equal to 1 or c is equal to 1
(b > a) b is greater than a
(a >= c) a is greater than or equal to c
(a + c == b) a plus c is equal to b
24. Variable Types
• When they first appear, they must
be declared using var
• Variable type must also be
declared (after the colon):
var moveX:Number = 10;
25. Variable types
Primitive: Complex:
Boolean Object
int Array
null Date
Number Error
Function
String
RegExp
uint
XML
undefined XMLList
• Declare any data type using an asterisk (*):
var myX:*;
26. Placement
• An instance of a movie clip can be
positioned at any location by
assigning values to the x and y as
coordinates:
myClip.x = 300;
myClip.y = 200;
27. Movement
• An instance of a movie clip can be
moved by adding a value to x or y:
myClip.x = myClip.x + 50;
myClip.y = myClip.y + 50;
29. Object Oriented Programming
• Object Oriented Programming (OOP)
is way of writing code that uses
objects as building blocks
• Your application can have many
objects, each based on a single
blueprint called a class
• Objects can have properties which is
the data that makes each object
unique
30. External ActionScript Files
• To place ActionScript in an external
file, rather than embedding it in
frames on the timeline, weʼre
required to use OOP
• Weʼll be creating an ActionScript
class to store our code
31. Your first ActionScript class
• Save your Flash file as
HelloWorld2.fla
• Go to New... > ActionScript File to
create a new external AS file
• Save the file using the same name
as your Flash file, example:
HelloWorld2.as
32. ActionScript Class
package {
import flash.display.*;
import flash.text.*;
public class HelloWorld extends MovieClip {
public function HelloWorld() {
var myText: TextField = new TextField();
myText.text = "Hello World!";
addChild(myText);
}
}
}
33. ActionScript Class
Class file declaration
package { Library classes needed
import flash.display.*;
import flash.text.*; Class definition
public class HelloWorld2 extends MovieClip {
public function HelloWorld2() {
var myText: TextField = new TextField();
myText.text = "Hello World!";
addChild(myText);
}
} Constructor
}
34. Constructors
• A constructor is a function that
executes as soon as the class loads
• Must be named the same as the
class
• Other functions come afterward
35. Putting it together
• To use the class in your Flash movie
you must associate it with the movie.
• In the Properties panel associate the
external AS file with HelloWorld.fla
by typing the filename into the class
field
36. Event Listeners
• By using an event listener that's triggered by
ENTER_FRAME the movie clip instance will move
on it's own
addEventListener(Event.ENTER_FRAME, myFunction);
myBtn.addEventListener(MouseEvent.CLICK, myFunction);
37. Homework, due March 2
• Read p41-64, Chapter 2:
ActionScript Game Elements in AS
3.0 Game Programming University
