VARIABLES IN FLASH
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In order to retrieve all the informationm we need to
store it into variables.
The primary information storage of Actionscript.
You can declare variables on a frame in the timeline or
directly on an object.
Define variables using the var keyword.
The general form to declare variables in flash:
var variableName:datatype;
VARIABLES IN FLASH
 variableName:
any valid Identifier.
 Ex)
id, myVariable, x
 3myVariable is invalid because it starts with a number.
 Datatype:
primitive data types (Number, String,
Boolean).
 There
are other built-in data types in flash (such as
Sound, Date, …)
PRIMITIVE DATA TYPES
1.
Number Data Type:

It is used to store numeric data types.
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
Numeric types could be integers (4,5,20) or floatingpoint numbers (2.4,4.321)
Ex) example on declaring numeric variable:
var f1:Number;

Ex) example on declaring a variable with initialization:
var f1:Number = 5;
PRIMITIVE DATA TYPES
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Ex) the following example shows how to deal with
number variables:
1.
2.
3.
Create a new flash file
Add a button symbol into the stage.
Add text field into the stage

Use the text field property inspector to change the text type to
(Dynamic Text). And, use it to give the inserted text field an
instance name (myText).
Text Type: Dynamic
Text (can be
changed during
running)
Instance name is
used to access the
object using Action
script
PRIMITIVE DATA TYPES
4.
In the action panel of the first frame, declare a variable (x)
of type Number and initialize it to 4.
5.
In the action panel of the button, write the following action
script:
On (press)
{
myText.text = x*x + 2*x +4;
}
6.
Test the movie
PRIMITIVE DATA TYPES
2.
Boolean Data Type:


It is used in logical operations to represent a
certain state.
It could only hold two values:
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true
false
Ex) var f2:Boolean = true;
PRIMITIVE DATA TYPES
3.
String Data Type:

It used to store data as a text ( a sequence of
characters).



Ex) “This is some text”
String in flash should be enclosed within double
quotation (“”)
Ex) to declare a variable (s) of type String and
store “some text” in it:
var s:String = “some text”;
PRIMITIVE DATA TYPES
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Each character in a string has an index.
The indices of characters are numbered (0,1,2,3,…)
from left to right.
The string characters created in the previous example
have indices as follows:
s o m e
t e x t
0 1 2 3 4 5 6 7 8
PRIMITIVE DATA TYPES

1.
Functions to manipulate string:
charAt(i);

This function returns a character from a string found in
index (i)
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
i: integer number represent an index.
Ex) var s:String = “some text”;
trace(s.charAt(2)); // m
2.
indexOf(str);


This function returns the index of the passed (str) within
the text.
Ex) trace(s.indexOf(“m”)); // 2
PRIMITIVE DATA TYPES
3.
length;


4.
Returns the number of characters in the string.
Ex) trace(s.length); //
9
substr(index,length);

Returns a part of the string as specified in the
parameters.

index: an integer gives the starting point of the taken part.
length: the number of characters to take starting at (index).

Ex) trace(s.substr(1,5));

// ome t
s o m e
t e x t
0 1 2 3 4 5 6 7 8
index
PRIMITIVE DATA TYPES
5.
toUpperCase();

6.
Returns the capital letter representation of the
string.
toLowerCase();
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Returns the lower letter representation of the
string.
STRING EXAMPLE
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Ex) this example illustrate how to build a flash
program to read string value from keyboard, convert
it to its capital representation, and print the result in
a text field on the stage:
1.
2.
Create a flash file.
Insert a text field on the stage, convert its type to (Input
Text) and give it an instance name (txtinput)


When you change the type of a text field to (Input Text), you can
insert text values into it at runtime from keyboard.
Giving an instance name to a text fields allow us to access it using
action script.
STRING EXAMPLE
3.
4.
5.
Insert a text field on the stage. Convert its type to dynamic
and give it an instance name (txtoutput)
Add a button on the stage. Insert the text (Convert to
Capital) in the button.
In the action pane of the button, add the following script:
on(press)
{
var s:String;
s = txtinput.text;
txtoutput.text = s.toUpperCase();
}
To take the text inserted
into (txtinput) and
assign it to (s)
To make return the
capital letter
representation of s.
Then assign it to
(txtoutput)
GLOBAL VARIABLE

Global variables are visible to every timeline and every
scene in your flash file.

To declare (or create) a variable with global scope, use
the _global identifier before the variable name and do
not use the var keyword.
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Ex) _global.myName = “globalvar";
FLASH SOUNDS
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There are two ways to add sounds to our flash file:
1.
import a sound file (in whatever format the flash editor
can handle, e.g. mp3, wav... etc), and pull it onto the
stage.
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Ex)
1.
2.
3.
4.
5.
6.
create new flash file
Go to FileImportImport to Library
Choose the sound file from your computer, and click open.
You can notice that your sound file was added to your library.
Now, Drag and drop that flash symbol into the stage.
Test the movie
FLASH SOUNDS
1.
if you want to have better control in playing the sound file,
you may need some actionscripts.


starting and stopping the music by pressing the corresponding
button.
Ex) This example illustrates how to control sounds inside flash
program.
1.
Open a new file in the Flash
2.
Import a sound file into the library.
MRC on the imported sound(in the library window; you may
need to open the library window first), and select linkage on
the pop up menu.
3.
FLASH SOUNDS
4.
check the export to actionscript option and type the name
"mysound" in the textbox.

5.
Ok, back to the main stage. Select the first frame on the
timeline, open the action window and put the following code in
it:

6.
This will assign an id to the imported sound, so later on the
actionscripts can refer to it.
var snd:Sound = new Sound();
snd.attachSound("mysound");
Basically, the above code will create a sound object and attach
the imported sound file to it.
insert a (play) button in the stage and write the following code
in the action pane of it:
FLASH SOUNDS
on(release)
{
_root.snd.start(0, 10);
}
_root: to access
every object in
the main
timeline
Action is performed
when releasing the
button
Start(0,10): This will
start playing the sound
(and loops 10 times)
when the button is
clicked.
FLASH SOUNDS
7.
Repeat step 6 to create the stop button but associated
with the following actionscritps instead:
on(release)
{
_root.snd.stop();
}
Stop(): to stop the
sound