This document provides information on adding text and arrays in Flash, including: 1) There are two ways to add text in Flash: using ActionScript or placing text directly on the stage. ActionScript allows dynamic text updates while on stage text is static. 2) Arrays can store multiple values in one variable and are useful for storing objects. Arrays use indexes to retrieve stored values. For loops can iterate through arrays to perform the same operation on each value. 3) The document demonstrates using arrays, for loops, and random numbers to generate multiple balls on the stage with random positions and velocities for an animation project timeline.

1. ARTDM 170, Week 13:
Flash Text + Arrays
Gilbert Guerrero
gguerrero@dvc.edu
gilbertguerrero.com/blog/artdm-170/

2. Text in Flash
• There are two basic ways to add text
to your Flash movies
‣ Using ActionScript
‣ Placing text on the stage

3. Text with ActionScript
gameScore = new TextField();
gameScore.x = 10;
gameScore.y = stage.stageHeight -30;
gameScore.width = 300;
var myTextFormat:TextFormat =
new TextFormat("Arial", 18, 0x006600,
true, false, false, null, null, "left");
gameScore.defaultTextFormat = myTextFormat;
gameScore.selectable = false;
gameScore.multiline = true;
gameScore.wordWrap = true;
gameScore.autoSize = TextFieldAutoSize.LEFT;
gameScore.text = "Your Score: 0”;
addChild(gameScore);

4. Placing text on the stage
• Use the text tool to add text to the
stage

5. Placing text on the stage
• Add an
instance name
• Select
Dynamic Text

6. Placing text on the stage
• In your ActionScript refer to the
instance name to update the text
value
myScore.text =
"Your Score: "+ numScore;

7. Updating the score
• In our jumping brick game, each time a
collision is detected with the myBalloon
object, we can update the score when
we remove the balloon
if( myBrick.hitTestObject(myBalloon) ) {
removeChild(myBalloon);
numBalloons = 0;
numScore = numScore + 1;
myScore.text = "Your Score: "+
numScore;
}

8. Adding a Timer

9. • Add a function that shows the time in
a text field
function showTime(event:Event){
gameTime = gameTimeLimit -
getTimer();
gameTimeField.text = "Time: "+
clockTime(gameTime);
}

10. Translate milliseconds using
this function
//Translates milliseconds to easily
readable Minutes and Seconds
public function clockTime(ms:int) {
var seconds:int = Math.floor(ms/1000);
var minutes:int = Math.floor(seconds/
60);
seconds -= minutes*60;
var timeString:String = minutes +":"+
String(seconds+100).substr(1,2);
return timeString;
}

11. Declare the new variables
private var gameTimeLimit:int;
private var gameTime:int;

12. Initialize and start the clock
gameTimeLimit = 20000;
addEventListener(
Event.ENTER_FRAME,showTime);

13. End the game when time has
run out
//end the game if time has run out
if(gameTime < 0) {
MovieClip(root).gotoAndStop(
"gameover");
}

14. Show the score on the Game
Over screen
//end the game if time has run out
if(gameTime < 0) {
MovieClip(root).numHits = numScore;
MovieClip(root).gotoAndStop(
"gameover");
}
• The score must be sent to a variable
at the root, numHits

15. On the root timeline
• In the first frame a variable must be
created
var numHits:Number;
• In the last frame, after it has received
data from the game, it is used to display
the score in the text field finalScore
finalScore.text = "YOUR SCORE: "+
numHits;

16. Arrays

17. What is an Array?
• Arrays group data together in a
single element
• Can be thought of as a variable that
stores variables
var arrayName:Array = new Array();

18. Storing and Retrieving
• Arrays can be used to store data
var fruits:Array = new Array();
fruits = [“apples”,“oranges”,“bananas”];
• Or:
var fruits:Array = new Array();
fruits[0] = “apples”;
fruits[1] = “oranges”;
fruits[2] = “bananas”;

19. Storing and Retrieving
• Data can be retrieved from arrays
using the index numbers
trace(fruits[0]); //apples
trace(fruits[1]); //oranges
trace(fruits[2]); //bananas
// I like to eat apples and oranges.
trace( "I like to eat "+ fruits[0] +" and
"+ fruits[1] +"." );

20. Arrays and Objects
• Arrays can be used to store objects
var redBall:Ball = new Ball();
var orangeBall:Ball = new Ball();
var yellowBall:Ball = new Ball();
var ballArray:Array = new Array();
ballArray = [redBall, orangeBall, yellowBall];

21. Arrays and Objects
• Instead of using the variable names for
each ball, we can use the array
ballArray[0].x = 100;
ballArray[0].y = 100;
ballArray[1].x = 200;
ballArray[1].y = 100;
ballArray[2].x = 300;
ballArray[2].y = 100;

22. for() loops
• for() statement allows you to repeat an
operation a certain number of times
for(var i:int=0; i < N; i++) {
trace(i);
}
• If N=3, then output would display:
0
1
2
The script runs while i is less than N, but not greater than
or equal to it

23. Using arrays and for loops
• In the case of our ballArray, we could
use a for() statement instead of typing
out every line
for(var i:int=0; i < 3; i++) {
ballArray[i].x = 100*(i+1);
ballArray[i].y = 100;
}
• The above code would set all the y
values to 100. The x values would be a
multiple of 100, i.e. 100, 200, and 300.

24. Creating multiples with arrays
• We can use a for() loop to create and add
the balls to an array
var ballArray:Array = new Array();
for(var i:int=0; i < 300; i++) {
var thisBall:Ball = new Ball();
ballArray.push(thisBall);
ballArray[i].x = 50*(i+1);
ballArray[i].y = 100;
}
• In this case we can create hundreds of
circles on the screen with a few lines of code

25. Randomization
• Generate a random number between 0
and .999999
Math.random()
• Round down using Math.floor and to
multiply Math.random by a number
get a random integer between zero and
your number
//generates integers from 0 to 29
Math.floor(Math.random()*30)

26. Randomizing location and
velocity
• Combining for() loops, arrays, and random
numbers we can create hundreds of objects
and give each one a different location and
velocity
for(var i:int=0; i < 300; i++) {
var thisBall:Ball = new Ball();
ballArray.push(thisBall);
ballArray[i].x = Math.floor(Math.random()*400);
ballArray[i].y = Math.floor(Math.random()*500);
ballArray[i].moveX = Math.floor(Math.random()*20);
ballArray[i].moveY = Math.floor(Math.random()*20);
}

27. Array Functions
• Add an item to the end of the array
fruits.push(“strawberries”)
;
• Remove an item from the middle of
an array
fruits.slice(5,1);
• More array functions: Chapter 5 in
AS 3.0 Cookbook

28. Script
package {
import flash.display.*;
import flash.events.*;
public class MyAnimation extends MovieClip {
// Setup the values
private var bounce:Number = -0.9;
private var gravity:Number = .5;
private var oldX:Number;
private var oldY:Number;
private var N:uint = 3;
private var ballArray:Array = new Array();
//Constructor
public function MyAnimation() {
init();
}
//Methods
public function init():void {
for (var i:uint = 0; i < N; i++){
var thisBall:Ball = new Ball();
ballArray.push(thisBall);
ballArray[i].graphics.lineStyle(5,0x000000);
ballArray[i].graphics.beginFill(0xCCCCCC);
ballArray[i].graphics.drawCircle(0,0,25);
ballArray[i].x = Math.floor(Math.random()*500);
ballArray[i].y = Math.floor(Math.random()*400);
ballArray[i].moveX = Math.floor(Math.random()*20);
ballArray[i].moveY = Math.floor(Math.random()*20);
addChild(ballArray[i]);
}
addEventListener(Event.ENTER_FRAME, onMoveCircle);
}
public function onMoveCircle(pEvent:Event):void {
for (var i:int = 0; i < ballArray.length; i++){
ballArray[i].moveY = ballArray[i].moveY + gravity;
ballArray[i].x = ballArray[i].x + ballArray[i].moveX;
ballArray[i].y = ballArray[i].y + ballArray[i].moveY;
if(ballArray[i].x > stage.stageWidth - ballArray[i].width/2 || ballArray[i].x < ballArray[i].width/2) {
ballArray[i].moveX = ballArray[i].moveX*bounce; //change direction
}
if(ballArray[i].y > stage.stageHeight - ballArray[i].height/2 || ballArray[i].y < ballArray[i].height/2) {
ballArray[i].moveY = ballArray[i].moveY*bounce; //change direction
}
}
}
}
}

29. Timeline
March April May Last day of class
9 16 23 30 6* 13 20 27 4 11 18 25
Create a project title and description
Present final projects
Paper prototypes (two days)
Design background, characters,
and other game elements
Embed game elements in game symbol
Add movement and keyboard interaction
Add Start and Game Over screens
Add scoring and game over trigger

30. Homework, due April 27
• Work on your final projects
• Read Getting Started on the
Processing site
Next week: Introduction to Processing